Acute Respiratory Viral Infection (ARVI): Clinical Guidelines

List of Abbreviations

IEI – inborn errors of immunity

ILI – influenza-like illness

IL – interleukin

CFU – colony-forming units

CG – clinical guidelines

MPVI – metapneumovirus infection

ARVI – acute respiratory viral infection

ARI – acute respiratory infection

RT-PCR – reverse transcription polymerase chain reaction

SmPC – Summary of Product Characteristics

RV – rhinovirus

RSVI – respiratory syncytial virus infection

CNS – central nervous system

PAT triage – Pediatric Assessment Triangle

ABCDE – universal primary assessment tool for critically ill patients, including children with respiratory infections (A — Airway, B — Breathing, C — Circulation, D — Disability, E — Exposure — measuring body temperature, examining the body for rashes)

CDS – Scale (Clinical Dehydration Scale – dehydration scale)

HPIV – human parainfluenza virus

HBoV – human bocavirus

PEWS – Scale (Paediatric Early Warning Score – Pediatric Early Warning Score)

Terms and Definitions

The term "acute respiratory viral infection (ARVI)" encompasses the following nosological entities: acute rhinopharyngitis, acute tracheitis, acute upper respiratory infection, unspecified.

New and narrowly focused professional terms are not used in these clinical guidelines.

1. Brief information on the disease or condition

1.1 Definition of the disease or condition

Acute respiratory viral infection (ARVI) is the most frequent acute respiratory infection manifested by catarrhal inflammation and accompanied by fever, rhinitis, sneezing, cough, sore throat, hoarseness, general malaise of varying severity, and in most cases resolving spontaneously (i.e., not requiring specific treatment).

Acute respiratory infection (ARI) of undetermined etiology: viral and/or bacterial (formerly referred to as acute respiratory disease (ARD)).

The term "acute respiratory viral infection (ARVI)" is used for the following nosological entities: acute rhinopharyngitis, acute pharyngitis, acute tracheitis, acute upper respiratory infection, unspecified.

1.2 Etiology and pathogenesis of the disease or condition (group of diseases or conditions)

The causative agents of ARI are predominantly viruses.

The seasonal complex of ARVI pathogens includes dozens of simultaneously circulating viruses (> 200 genetic groups from 10 genera and 7 families); however, the clinical presentation of ARVI is practically independent of the etiology (Appendix A3.2), and the formulation of the diagnosis should primarily reflect the nosological entity (Appendix A3.3).

The spectrum of ARVI pathogens causing annual worldwide epidemics in the autumn-winter period comprises representatives of five RNA virus families (Orthomyxoviridae, Paramyxoviridae, Coronaviridae, Pneumoviridae, and Picornaviridae) and two DNA virus families (Parvoviridae and Adenoviridae). Orthomyxoviruses include influenza viruses (Influenza A and B virus). Paramyxoviruses include human parainfluenza viruses (HPIV 1–4), as well as measles and mumps viruses. Coronaviruses are represented by seasonal viruses (HCoV-OC43, HCoV-HKU1, HCoV-229E, and HCoV-NL63) and SARS-CoV-2. Human metapneumovirus (MPV) and human respiratory syncytial virus (RSV), previously classified as paramyxoviruses, are now classified in a separate family, Pneumoviridae. Respiratory viruses from the family Picornaviridae are the most diverse, including human rhinoviruses (over 150 serotypes) and enteroviruses, including multiple serotypes of Coxsackie viruses and echoviruses. Among parvoviruses, human bocavirus (HBoV) and parvovirus B19 (the causative agent of erythema infectiosum) are of clinical importance. Adenoviruses are subdivided into 7 subgroups (A, B, C, etc.) and over 80 serotypes [1]. The species and serotype diversity of respiratory viruses implies their immunological diversity; therefore, a child's "naive" immune system perceives the viral serovariants as new pathogens, and infection is accompanied by ARI symptoms. As a result of natural contact with numerous immunologically diverse viruses and the development of cross-immunity, the frequency of ARVI decreases with age.

The circulation of SARS-CoV-2 has complicated the identification of the etiology of seasonal epidemic outbreaks with respiratory transmission.

The high incidence of ARVI after the COVID-19 pandemic against the background of a decreased detection rate of SARS-CoV-2 RNA indicates an increased relevance of traditional seasonal (year-round) ARVI pathogens in the human population [2].

Viruses are most commonly spread by self-inoculation onto the nasal mucosa or conjunctiva from hands contaminated through contact with an infected person (e.g., via a handshake) or contaminated surfaces.

The airborne droplet route of transmission occurs when inhaling aerosol particles containing the virus, or when larger droplets land on mucous membranes during close contact with an infected person.

The incubation period for most viral infections ranges from 2 to 7 days. Viral shedding in patients peaks on day 3 post-infection, followed by a rapid decline by day 5; low-intensity viral shedding may persist for up to 2 weeks.

ARVI symptoms result not so much from the damaging effect of the virus as from the immune system response. Affected epithelial cells release cytokines, including interleukin 8 (IL-8), the level of which correlates both with the degree of phagocyte recruitment into the submucosa and epithelium and with the severity of symptoms. Increased nasal secretion is associated with elevated vascular permeability and may be accompanied by a multiplefold increase in leukocyte count in nasal secretions, changing its color from clear to yellowish-white or greenish; therefore, considering a change in nasal mucus color as a sign of bacterial infection is groundless [3].

The assumption that bacterial flora is activated in any viral infection (the so-called "viral-bacterial etiology of ARI") based, for example, on the presence of leukocytosis in the patient, is not supported by practice. Bacterial complications of ARVI occur relatively infrequently.

Features of the infectious process depending on the type of pathogen.

Rhinovirus (RV) infection: accounts for 25–40% of ARVI cases; the causative agents are RNA viruses of the genus Rhinovirus, family Picornaviridae, genus Enterovirus (human enterovirus D [HEV-D]) [4, 5]. RVs are unstable in the external environment, being inactivated at 50°C within 10 minutes; when exposed to air, most virions lose infectivity within a few minutes, although infectivity on surfaces persists for up to 1 day. The reservoir and source is an infected person. Pathogen shedding: begins 1 day before disease manifestation, duration 5–10 days. Rhinovirus infection is ubiquitous, registered year-round in temperate climates as local outbreaks with increased incidence in spring and autumn. Children under 5 years old are most frequently affected, though people of all ages are susceptible.

RV infection manifests primarily as rhinitis; however, the virus also exhibits tropism for the lower respiratory tract epithelium, being an etiological factor of acute bronchitis among other conditions. There is convincing evidence of the role of rhinovirus infection in the development/triggering of bronchial obstruction and asthma exacerbations [6].

Despite antibodies persisting for a long time after RV infection (for several years), reinfection is possible upon infection with a different rhinovirus serotype [7, 8].

Adenovirus infection. Adenoviruses are DNA-containing viruses, family Adenoviridae, genus Mastadenovirus. Over 80 serotypes belonging to 7 subgroups (A, B, C, D, E, F, G) have been described. The antigenic structure of adenoviruses is represented by three antigens: A-antigen, a group antigen common to all serotypes; B-antigen, a toxic antigen causing a cytopathic effect in tissue culture and suppressing interferon activity; C-antigen, a type-specific antigen [4]. Adenovirus infection affects the respiratory epithelium, lymphoid tissue, conjunctiva, and intestine. Adenoviruses are highly stable in the external environment. The virus remains viable at room temperature for up to 2 weeks and withstands low temperatures and desiccation. However, it is inactivated by ultraviolet rays and chlorine-containing disinfectants.

Adenoviruses are not dangerous for children under 6 months of age due to maternal antibodies. Subsequently, a child may contract adenovirus infection several times, gradually developing acquired immunity. The likelihood of adenovirus infection decreases with age.

Adenovirus infection is ubiquitous, and outbreaks are possible, especially in organized childcare groups [8].

Respiratory syncytial virus infection (RSVI) is a highly contagious respiratory infection.

The causative agent of the infection is an RNA-containing virus of the family Pneumoviridae, genus Pneumovirus. The antigenic composition of the virus is stable; all known variants pathogenic to humans belong to a single serotype, while there are two pathogen subtypes: A and B with different surface G proteins. A common stable component of all subtypes is the F protein. The G protein mediates attachment of RSV to the cell wall, while the F protein mediates fusion with the epithelial cell of the respiratory tract mucosa.

RSV infection is ubiquitous; in recent years—following the novel coronavirus infection (COVID-19) pandemic—a clear seasonality of the infection has not been observed. Immunity following the infection is unstable, and a child can contract RSV infection repeatedly not only throughout life, but even within a single epidemic season. Cases of reinfection are less severe [4, 7, 8, 9, 10].

Both mild and severe courses of RSV infection are possible in children. A severe form of RSV infection presenting as bronchiolitis with respiratory failure is characteristic of children in the first two years of life; bronchitis and pneumonia may also be observed in children older than 2 years with an burdened premorbid background (bronchial asthma, immunodeficiency, and other chronic conditions). Evidence suggests that RSV infection contracted at an early age is one of the factors increasing the risk of developing bronchial asthma and COPD later in life, especially with an burdened allergic history [11].

Passive immunization is available for the prevention of RSV infection in high-risk children under 2 years of age.

Metapneumovirus infection (MPI). Human metapneumovirus is an RNA-containing virus of the family Pneumoviridae, genus Metapneumovirus. Manifestations of MPI can range from mild and minor to severe in the form of bronchitis, bronchiolitis, or viral pneumonia, similar to those of RSV infection. Metapneumovirus is characterized by seasonality with a peak in winter and early spring. Among young children hospitalized with acute respiratory viral infections (ARVI), metapneumovirus is detected in 5–10% of cases [12, 13, 14].

Influenza is caused by RNA-containing viruses from the family Orthomyxoviridae, genus Influenza virus, including types A, B, and C. Influenza viruses are characterized by antigenic variability, which determines high human susceptibility. Influenza is ubiquitous, with intervals between epidemics averaging 1–2 years for influenza A and 2–4 years for influenza B. All age groups are affected. The replication of new virions is accompanied by a cytopathic effect on the respiratory epithelial cells, their destruction, and shedding along with newly formed virions. In severe infection, the influenza virus also replicates in vascular endothelial cells, leading to endotheliosis manifested as cellular necrosis and apoptosis, increased capillary permeability, and in the most critical cases, circulatory disorders. Influenza presents with rhinitis, pharyngitis, tracheitis, laryngitis, bronchitis, or combinations thereof. One of the most severe variants of this process, caused by a novel (pandemic) pathogen, is the development of massive pneumonia with acute respiratory distress syndrome (ARDS) and pulmonary edema (for details, see the relevant clinical guidelines) [7, 14, 15].

Vaccination against influenza is available.

Parainfluenza (or parainfluenza infection) - an ARVI caused by human parainfluenza virus (HPIV). An RNA virus belonging to the family Paramyxoviridae, order Mononegavirales, genus Respirovirus for types 1 and 3, and Rubulavirus for types 2 and 4. HPIV-1 and HPIV-3 are among the leading causes of lower respiratory tract infections in young children (under 5 years of age) and immunocompromised individuals. It most frequently presents as an upper respiratory tract infection, involving the nasopharyngeal and laryngeal mucosa. In young children, parainfluenza can be severe, leading to "croup" (acute obstructive laryngitis) (see relevant clinical guidelines).

Parainfluenza infection is ubiquitous and occurs more frequently in autumn and spring, although the seasonality of HPIV infection may vary depending on the virus type. For example, HPIV-1 peaks biennially from September to December, whereas HPIV-3 peaks annually, predominantly from April to June. In years when HPIV-1 does not circulate, HPIV-3 is frequently encountered over a more prolonged period, extending into autumn with a secondary surge in activity from November to December of the same year. HPIV-2 may occur biennially, alternating with HPIV-1, or annually. HPIV-4 is less common, with a seasonality similar to HPIV-3. Outbreaks of parainfluenza infection are more frequently observed in organized groups. Immunity following parainfluenza is unstable: reinfection with upper respiratory tract involvement is possible after 3–4 years [16].

Coronavirus infection (seasonal). Coronaviruses (Coronaviridae) are a family of RNA-containing viruses that currently account for up to 30% of seasonal ARVI cases in children. Four genera of viruses are known: alpha, beta, gamma, and delta. Transmission routes: airborne droplet, contact, fecal-oral. Incubation period: 2–3 days. Involvement of the respiratory tract (rhinitis, pharyngitis, dry cough) and gastrointestinal tract (diarrhea) is most common, with involvement of other organs occurring in rare cases [17, 18].

Bocavirus infection is caused by human bocavirus (HBoV), a virus of the family Parvoviridae, genus Bocaparvovirus. Clinically, HBoV infection manifests as rhinopharyngitis, occasionally bronchitis (including obstructive bronchitis), and may exacerbate asthma symptoms. Moderately severe forms of the disease are most common. Certain forms of bocavirus cause gastroenteritis [19, 128].

1.3 Epidemiology of the Disease or Condition

ARVI is the most common human infection: children under 5 years of age experience an average of 6–8 episodes of ARVI per year [20, 21]. The incidence is particularly high in preschool childcare facilities during the 1st–2nd year of attendance—10–15% higher than in children cared for at home, whereas school-aged children cared for at home fall ill more frequently [22]. With age, the frequency of ARVI generally decreases unless the patient has an burdened premorbid background or is immunocompromised. The incidence is highest from September to April, typically peaking in February-March, while during the summer months, the incidence of ARVI drops 3-5 fold.

According to Rospotrebnadzor data, in 2024, 21.5% of the country's population suffered from ARVI (for comparison: 23.6% in 2023, and 29.1% in 2022). A total of 31.4 million cases of ARVI were registered in the Russian Federation in 2024 (21,457.88 per 100,000 population). The incidence in children under 17 years of age amounted to over 17.9 million cases, or 59,711.52 per 100,000 population. Among the pediatric population, the highest incidence is consistently registered in the 1–2 year age group (92,699.4 per 100,000 population) [23].

The cited data reflect the number of ARVI cases registered based on medical visits; the true incidence is undoubtedly significantly higher.

The prevalence of ARVI is associated with the presence of an incredible variety of respiratory pathogens, the development of only type-specific post-infection immunity, and the ease of pathogen transmission. Infants in the first months of life rarely fall ill because they are in relative isolation, and many of them retain for some time immune factors acquired transplacentally and via breast milk. The highest incidence is observed among children aged 3 to 6 years, which is generally associated with attending childcare facilities, a significant increase in the number of contacts, and exposure to a new viral-bacterial landscape. The spectrum of pathogens varies, but it is determined by the season of the year and the patient's age. Etiological identification is possible in up to 80% of cases upon hospitalization [24].

1.4 Features of Coding the Disease or Condition

ICD-10 Coding

J00 - Acute nasopharyngitis [common cold]¹

J04.1 - Acute tracheitis

J06.0 - Acute laryngopharyngitis

J06.8 - Other acute upper respiratory infections of multiple sites

J06.9 - Acute upper respiratory infection, unspecified

J39.9 - Disease of upper respiratory tract, unspecified

B34.0 - Adenovirus infection, unspecified site

B34.2 - Coronavirus infection, unspecified site

Excluded:

severe acute respiratory syndrome [SARS], unspecified (U04.9)

COVID-19, virus identified (U07.1)

COVID-19, virus not identified (U07.2)

Notes:

¹ - Acute nasopharyngitis – according to the classification of meningococcal infection by V.I. Pokrovsky – is used exclusively to define the localized form of meningococcal infection; in the context of the present clinical guidelines, the code is used to designate acute rhinopharyngitis or acute rhinitis.

1.5 Classification of the disease or condition

Criteria for determining the severity of acute respiratory viral infections (ARVI) (pharyngitis, laryngitis, tracheitis) are still under discussion.

Body temperature values in children are not indicative of the severity of a patient's condition with an acute respiratory infection [25]. Life-threatening conditions can also be observed in the absence of elevated body temperature in a child.

It is also necessary to keep in mind risk groups (including children with severe premorbid conditions), which require increased attention due to the higher probability of complications even with a mild course of ARVI. Thus, in clinical practice, patient risk stratification is of paramount importance.

ARVI forms can be conditionally classified by severity into the following:

- mild form – cases of the disease proceeding with mildly pronounced intoxication symptoms and unobtrusive local changes;

- moderate form – cases of the disease in which intoxication symptoms are moderately pronounced: headache, weakness, poor appetite, and abdominal syndrome are possible;

- severe form – cases of the disease with pronounced impairment of the general condition, repeated vomiting / cardiovascular changes / pronounced local manifestations, severe metabolic disorders; dizziness / delirium / seizures / hallucinations, etc., are possible.

Indicators of particular severity include convulsive, meningeal, and hemorrhagic syndromes, signs of encephalitis, and hypothermia [8].

One should be guided by the criteria used for triage and appropriate routing of patients with signs of respiratory infection (see algorithms B1, B2, Section "Organization of Medical Care") and the dynamics of the patient's condition.

1.6 Clinical presentation of the disease or condition

The disease usually begins acutely, often accompanied by an increase in body temperature to subfebrile figures (37.5°C–38.0°C). Febrile fever is more characteristic of influenza, adenovirus infection, and enterovirus infections. Elevated temperature in 82% of patients decreases by the 2nd–3rd day of the illness; fever persists longer (up to 5–7 days) in influenza and adenovirus infection [26]. An increasing fever level during the course of the disease and symptoms of bacterial intoxication in a child should raise suspicion of a secondary bacterial infection. A secondary temperature spike after a short-term improvement often occurs with the development of acute otitis media against the background of prolonged rhinitis.

Rhinopharyngitis (rhinitis)

Rhinitis is characterized by complaints of nasal congestion, nasal discharge, and discomfort in the nasopharynx: burning, tingling, dryness, often accumulation of mucous discharge which, flowing down the posterior pharyngeal wall, can cause a productive cough and sneezing. Manifestations peak on days 1–3, and their duration usually does not exceed 6–8 days. Headache is noted among general symptoms [27].

When inflammation spreads to the mucous membrane of the auditory tubes (eustachitis), clicking, noise, and pain in the ears appear, and hearing may decrease. In infants, against the background of pronounced nasal breathing difficulty, restlessness, and difficulties with feeding and falling asleep may be observed [27].

Laryngitis

A characteristic symptom of laryngitis is hoarseness. Unlike croup syndrome (obstructive laryngotracheitis), laryngitis is not accompanied by laryngeal stenosis or respiratory failure. A harsh dry cough may be noted (see Clinical Guidelines "Acute Laryngitis").

Pharyngitis

Pharyngitis reveals hyperemia and edema of the posterior pharyngeal wall, and its granularity caused by hyperplasia of lymphoid follicles. A small amount of mucus may be noticeable on the posterior pharyngeal wall (catarrhal pharyngitis) [27]; pharyngitis is also characterized by a non-productive, often nagging cough. This symptom causes extreme anxiety for parents and discomfort for the child, as the cough can be very frequent (see Clinical Guidelines "Acute Tonsillitis and Pharyngitis (Tonsillopharyngitis)").

Tracheitis

Tracheitis is characterized by a nagging, frequent, and debilitating cough that subsequently becomes wet and productive. Symptoms of tracheitis in ARVI can last up to 10–14 days [27].

2. Diagnostics, medical indications and contraindications for diagnostic methods

There are no universally accepted criteria for upper respiratory tract ARVI.

Catarrhal inflammation of the upper respiratory tract is observed, along with possible fever, sneezing, cough, sore throat, hoarseness/voice changes, impaired sense of smell, and impaired general condition.

ARVI in children is diagnosed based on the analysis of complaints, medical history, clinical examination, assessment of the epidemiological history, and, if necessary, laboratory and special examination methods. Diagnostics are primarily aimed at identifying complications, choosing treatment tactics, and patient routing.

Approximate clinical and laboratory parameters for systemic inflammatory response syndrome in children are presented in Appendix A3.4.

2.1 Complaints and Anamnesis

The patient or parents (legal representatives) may complain of acutely onset rhinitis and/or cough (sometimes conjunctival hyperemia in catarrhal conjunctivitis combined with manifestations of rhinitis and pharyngitis).

When taking the medical history, attention should be paid to:

- epidemiological history data: stay in an ARVI focus, morbidity in a children's institution, contacts with sick children and adults during the incubation period;

- presence of an epidemic surge in ARVI incidence;

- seasonality of ARVI (autumn-winter, winter-spring period) with a peak in incidence;

- nature and duration of complaints and clinical manifestations: general malaise, fever, fatigue, weakness, decreased appetite, refusal of mother's breast or difficulty feeding in infants, unmotivated anxiety, headaches, sore throat, nasal breathing difficulty, runny nose (rhinorrhea), hoarseness, cough (dry and wet), enlarged lymph nodes, abdominal pain.

In the complicated course of ARVI, shortness of breath manifested as difficulty breathing in and/out, a feeling of palpitations or heart interruptions, as well as severe headaches may appear, and in some cases – nausea, vomiting, seizures, and loss of consciousness (symptoms of neuroinfection with clinical features of cerebral edema);

- disease duration and temperature tolerance (including the presence of febrile seizures, history of convulsive syndrome), dynamics of clinical symptoms (a change in symptoms is typical for the inflammatory process in ARVI – nasal congestion may be replaced by rhinorrhea, dry cough gradually becomes productive, temperature in the first 3–4 days may remain at febrile levels, then gradually decreases to subfebrile figures);

- presence of concomitant chronic diseases to identify risk factors for a complicated course (ARVI is a provoking factor for the development of exacerbations of chronic diseases);

- assessment of the vaccination status in all children (including maternal vaccination during pregnancy for children of the first 6 months of life) and the presence of passive immunization against RSV infection in children in risk groups (for risk groups, see CG "Acute Bronchiolitis").

2.2 Physical Examination

Examination involves assessing the general condition and physical development of the child, measuring temperature, counting the respiratory rate and heart rate, examining the upper respiratory tract and oropharynx, palpation and percussion of the chest, lung auscultation, and abdominal palpation (carried out as part of the primary and follow-up appointment (examination, consultation) of a pediatrician / primary and follow-up appointment (examination, consultation) of a district pediatrician / primary and follow-up appointment (examination, consultation) of a general practitioner (family physician) / primary and follow-up appointment (examination, consultation) of an infectious disease specialist).

Comments: at the initial stage of diagnosis, acute respiratory viral infections (ARVI) present with catarrhal symptoms, and in some cases, tenderness and enlargement of regional lymph nodes. However, the above symptoms may also manifest in certain bacterial infections, notably streptococcal tonsillopharyngitis (see the clinical guidelines "Acute Tonsillitis and Pharyngitis (Acute Tonsillopharyngitis)".

Comments: physical examination allows for the detection of changes characteristic of bronchitis, bronchoconstrictive syndrome, and the appearance of local symptoms typical of pneumonia (see the clinical guidelines "Bronchitis" (pediatric age group), "Pneumonia (Community-Acquired)" (pediatric age group over 1 month)).

Comments: in ARVI caused by adenovirus infection, gastrointestinal involvement is possible, accompanied by nausea, vomiting, and diarrhea. The presence of hepatomegaly with or without splenomegaly may indicate infectious mononucleosis (Epstein-Barr virus, cytomegalovirus, human herpesvirus type 6).

Comments: infectious diseases affecting the central nervous system may initially manifest as catarrhal symptoms typical of ARVI (including measles).

Comments: for every 1°C increase in body temperature, fluid and electrolyte losses increase by approximately 10% [36]. Prolonged febrile states in children with ARVI may be accompanied by dehydration syndrome and electrolyte imbalances.

To assess the degree of dehydration, it is advisable to use the CDS scale (Appendix G1) [322].

2.3 Laboratory Diagnostics

Laboratory tests in uncomplicated ARVI in an outpatient setting are generally not required.

In an inpatient setting, a complete blood count (CBC) is performed for all patients; serum C-reactive protein measurement is optional when bacterial infection is suspected. The scope of other laboratory tests is determined by the clinical situation.

The primary goal of laboratory evaluation in a patient with ARVI is to detect complications, including bacterial ones, and, if necessary, to determine the etiology of the disease.

Comment: for details, see the clinical guidelines "Acute Tonsillitis and Pharyngitis (Tonsillopharyngitis)" (pediatric and adult age groups).

Comment: a case of influenza is considered confirmed after laboratory verification of the diagnosis (using any standardized methods approved in the Russian Federation and recommended for the diagnosis of influenza, or using medical devices authorized for influenza diagnostics in the Russian Federation).

During periods of epidemic peaks in influenza incidence, a definitive diagnosis of "influenza" can be established both on the basis of laboratory confirmation and on clinical and epidemiological data.

In the presence of typical symptoms and the inability to determine their etiology, the term "influenza-like illness" (ILI) proposed by WHO, along with the terms ARI (acute respiratory infection) and SARI (severe acute respiratory infection), may be used for more accurate and rapid diagnosis and treatment.

The use of rapid tests for viral infections in emergency departments and hospital admission units can reduce the risk of unjustified antibiotic therapy and unnecessary diagnostic tests, including chest radiography [40].

PCR is an effective diagnostic method that can detect viral nucleic acids on average up to 7 days, and at most up to 2 weeks from symptom onset (provided upper respiratory tract involvement persists). Results are obtained within 4–6 hours after sample submission.

In all other cases, etiological diagnostics is performed optionally (see below).

Comments: modern multiplex panels using molecular methods allow the detection of dozens of viruses and bacteria within a few hours. However, they are mainly available in large inpatient facilities equipped with special facilities and properly qualified personnel. In most cases, the detection of microorganisms does not necessarily indicate their etiological significance in the current acute respiratory viral infection (ARVI), as asymptomatic carriage is possible. Given the limited options for etiotropic therapy of viral diseases, the need for routine virus verification is questionable. Virological and bacteriological methods for ARVI are in demand for epidemiological and clinical studies, as well as for the examination of immunocompromised patients.

Performed when necessary and feasible (most commonly in inpatient settings).

• Routine (clinical) urinalysis (including using test strips in outpatient settings and hospital admission departments) is recommended when a urinary tract infection is suspected in children with ARVI, including febrile children without catarrhal symptoms, for the timely diagnosis of urinary tract infection [42, 43].

GCR CLOC 3Level of recommendations grading — C (level of evidence certainty - 3).

Comments: 5–10% of infants and young children with a urinary tract infection also have a viral co-infection with clinical signs of ARVI. At the same time, urinalysis in children with nasopharyngitis or laryngitis without fever is performed only in the presence of complaints or specific recommendations due to concomitant urinary system pathology (see clinical guidelines "Urinary tract infection" (pediatric age group)).

• Complete blood count (CBC) is recommended in children with ARVI and fever when prominent systemic symptoms are present [42, 43, 44].

GCR CLOC 3Level of recommendations grading — C (level of evidence certainty - 3).

Comments: an elevated level of inflammatory markers, including bacterial ones, is an indication to screen for complications, primarily "silent" pneumonia, acute otitis media, and urinary tract infection.

When analyzing the results, the specific features of laboratory parameters in certain viral infections should be taken into account:

- leukopenia, characteristic of influenza and enteroviral infections, is usually absent in other ARVIs;

- respiratory syncytial virus (RSV) infection is accompanied by lymphocytic leukocytosis, which may exceed 15 × 10⁹/L;

- in adenovirus infection, leukocytosis can reach 15–20 × 10⁹/L or even higher, with possible neutrophilia greater than 10 × 10⁹/L and C-reactive protein levels exceeding 30 mg/L;

Repeat clinical blood and urine tests are required only if abnormalities are detected during the initial examination or if new symptoms appear that necessitate further diagnostic workup.

If the symptoms of the viral infection have resolved, the child is no longer febrile, and feels well, repeating the complete blood count is inappropriate.

• Determination of serum C-reactive protein (CRP) level is recommended selectively when it is necessary to rule out a bacterial infection in children with ARVI presenting with febrile fever (temperature elevation above 38°C), especially in the absence of a discernible focus of infection [42, 43, 44].

GCR CLOC 3Level of recommendations grading — C (level of evidence certainty - 3).

Comments: levels above 50 mg/L are more characteristic of bacterial infections (according to the reagent instructions).

According to published data, the CRP cut-off thresholds for suspecting a bacterial infection range from 40 to 100 mg/L. Therefore, the CRP level must be evaluated in conjunction with the patient's overall status and clinical manifestations.

It should be remembered that low CRP values in the first 12 hours of fever do not rule out a bacterial infection, as this is a feature of its kinetic rise (low CRP levels can be obtained within this time interval even in the presence of a confirmed bacterial focus). In addition, in patients with liver disease (hepatic failure and liver cirrhosis) and immunodeficiency states, CRP levels may also be low and fail to reflect the presence of a bacterial infection [323, 324, 325, 326, 327, 328, 329].

Attention should also be paid to evaluating CRP dynamics and the rate of its increase, which can help in the differential diagnosis of ARVI and bacterial infection [330]. Routine blood procalcitonin testing is not indicated [43, 44].

2.4 Instrumental Diagnostics

Comments: pulse oximetry is a simple screening method that allows for the identification of patients with hypoxemia who require respiratory support and for assessing its efficacy.

• Chest radiography (lung X-ray) and/or spiral computed tomography (CT) of the lungs are not recommended for every child with ARVI symptoms in order to avoid unnecessary radiation exposure [48, 49, 50].

GCR CLOC 1Level of recommendations grading — C (level of evidence certainty - 1).

Comments: indications for chest X-ray are provided in the clinical guidelines "Pneumonia in children";

It should be remembered that the detection of accentuated bronchovascular markings or widened lung root shadows on a chest X-ray is insufficient to establish a diagnosis of "pneumonia" and is not an indication for antibacterial therapy.

In questionable cases, spiral computed tomography of the lungs may be performed (see clinical guidelines "Bronchitis" (pediatric age group), "Pneumonia (community-acquired)" (pediatric age group)). This study is also indicated when a novel coronavirus infection (COVID-19) is suspected.

Unnecessary radiation exposure should be avoided due to the increased risk of cancer development in children [50].

• Paranasal sinus radiography is not recommended for patients with ARVI and acute rhinitis/rhinosuritis during the first 10–14 days of illness in the absence of signs of acute bacterial sinusitis, in order to avoid unnecessary radiation exposure [51].

GPP CLoE 5Level of Evidence/Grade of Recommendation – C (level of evidence - 5).

Comments: performing paranasal sinus radiography in the early stages of the disease often reveals virus-induced paranasal sinus inflammation that resolves spontaneously within 2 weeks [37, 51].

When deciding on the need for examination, one should be guided by the clinical guidelines "Acute sinusitis" (adult/pediatric age group).

For necessary examinations when acute bacterial sinusitis is suspected, see the clinical guidelines "Acute sinusitis" (adult/pediatric age group).

Comments: the study should be performed in patients with severe and complicated ARVI, congenital heart disease, a history of myocardiopathy or myocarditis, and when clinical signs of cardiac arrhythmia are present.

Comments: the method should be used in patients with decompensation of underlying neurological pathology, development of afebrile seizure syndrome, or suspected cerebral edema, meningitis, or encephalitis against the background of acute respiratory viral infections (ARVI)/influenza.

2.5 Other Procedures

3. Treatment, including drug and non-drug therapies, diet therapy, and pain management

3.1 Conservative Treatment

ARVI is the most common reason for the use of various drugs and procedures, most often unnecessary, with unproven efficacy, and frequently causing adverse effects. Therefore, it is very important to explain the benign nature of the disease to parents, inform them of the expected duration of symptoms, and convince them that minimal interventions are sufficient.

The mainstay of ARVI treatment is symptom relief [60].

Treatment tactics are chosen based on the following factors: the period and clinical form of the disease; leading clinical manifestations and features of the disease course, taking into account comorbid conditions, including signs of immunodeficiency, and the patient's age; presence and nature of complications; availability and feasibility of treatment in accordance with the required type of medical care.

Etiotropic (antiviral) therapy is not a routine component of medical treatment for ARVI; most respiratory viral infections do not require antiviral/immunomodulatory therapy. Etiotropic treatment has been developed only for influenza [61, 62].

The advisability of prescribing antiviral therapy is determined by the physician individually for each patient [63]. When deciding on its use, caution should be exercised, and the benefit/harm ratio must be considered.

3.1.1 Symptomatic Therapy

Comments: elimination therapy is safe and effective. A nasal douche or nasal spray can be used.

In infants and young children with abundant discharge, mucus aspiration from the nose using a special manual aspirator followed by the administration of sodium chloride (0.9%) (starting from 2 years of age) is effective. Elevating the head of the crib can help facilitate nasal mucus drainage.

Sprays containing isotonic sodium chloride solution or sterile sea water solution are used in older children in accordance with the instructions/SmPC.

There are recommendations on the potential use of sea water (hypertonic solutions) for nasal congestion [64, 196]. However, it should be borne in mind that the use of sea water (hypertonic solution) may cause unpleasant sensations, including pain, and therefore the expected potential benefits and harms of this intervention should be carefully weighed before prescribing it.

Comments: the use of systemic drugs containing decongestants is highly undesirable [199].

Comments: a febrile child is uncovered and cautiously wiped with water at a temperature of 25–30 °C. In some cases, this method distresses the child, providing only temporary relief [65].

Physical cooling methods should not be used in "pale" fever.

Comments: the World Health Organization (WHO) defines fever as an axillary temperature of ≥ 37.5 ºC [66].

Antipyretic therapy in healthy children aged ≥ 3 months is justified at temperatures above 38.5 ºC (measured axillary or above 39–39.5 °C measured rectally).

In children under 3 months of age, patients with chronic pathology, and in cases of temperature-related discomfort, temperature-lowering agents may also be used at a lower grade of fever.

To minimize the risk of adverse reactions to paracetamol**, the first dose should be given orally [69].

Regular (scheduled) administration is undesirable; a repeated dose is administered only after a new temperature rise, strictly observing the interval between doses [22, 43, 198]. The drug can be used orally or in the form of rectal suppositories; paracetamol** for intravenous administration is also available. However, the rectal route of administration for antipyretic purposes has limitations in determining the correct dose due to variable intestinal absorption, and therefore rectal forms are considered for prescription only in the presence of vomiting or other intolerance to the oral route [70].

Multiple antipyretic drugs should not be alternated or used simultaneously, nor should they be taken on a scheduled course.

Strict adherence to the intervals between doses of paracetamol** and ibuprofen** is required.

A single administration of the drug is usually effective and safe, but it should be remembered that subsequent doses may cause adverse reactions and toxic effects.

In most cases, fever is caused by a self-limiting viral infection, although bacterial complications and other causes may need to be ruled out [71].

With fever, it can be difficult to recognize a bacterial infection in a timely manner. Bacterial infections are more common in children under 1 year of age.

Any fever in an infant under 3 months of age is serious and requires thorough evaluation and referral to a specialist or hospital [70].

It should be remembered that the use of antipyretic therapy together with systemic antimicrobial drugs can "mask" the ineffectiveness of the latter.

Comment: this is because their antipyretic effect is based on the suppression of components involved in the acute phase of the inflammatory response, such as interleukin-1 and -6, and tumor necrosis factor-alpha. In general, systemic corticosteroids have an immunosuppressive effect, which also indirectly leads to a decrease in body temperature [72]. In many infectious nosologies, which are typically accompanied by fever, the use of these drugs has not shown the proper clinical effect or has led to the development of life-threatening complications [73, 74, 75, 76, 77, 78, 79, 80, 81].

• In children, acetylsalicylic acid** is not recommended for antipyretic purposes due to the high risk of adverse reactions [275].

GPP CLoE 5Level of Evidence/Grade of Recommendation – C (level of evidence - 5).

• In children, the use of nimesulide as an antipyretic is not recommended due to the potential risk of adverse reactions [201].

GCR CLOC 4Level of recommendations grading — C (level of evidence certainty - 4).

Comments: metamizole sodium may be prescribed on a situational, single-dose basis only in exceptional cases, including intolerance to paracetamol** or ibuprofen**, or when parenteral antipyretic therapy is necessary and no alternatives are available, after assessing the risks and expected benefits [206, 207].

It should be noted that when metamizole sodium is used during fever or antibacterial therapy, some early symptoms of agranulocytosis may remain unnoticed [82, 84, 85, 86].

Comments: in most cases, febrile seizures are "benign" and there is no evidence supporting the feasibility of their prevention.

Parents should be trained to recognize seizures.

Further studies in children with recurrent febrile seizures may help clarify risk factors and identify subgroups of children who might benefit from prophylactic anticonvulsant therapy.

Comments: there is evidence that these interventions may alleviate symptoms [93, 94, 276, 277, 278], but currently there is insufficient evidence for definitive conclusions [95]. They may be prescribed selectively and with caution at the physician's discretion.

Comments: dry, persistent cough in ARVI accompanied by pharyngitis or laryngotracheitis can be suppressed in exceptional cases using butamirate (the evidence base for its use is small) [320, 321], levodropropizine [96], or prenoxdiazine (used in accordance with the instructions/SmPC).

Comments: mucolytic agents should be prescribed in short courses with an assessment of potential risks and benefits, under efficacy monitoring, and with caution—especially in children under 2 years of age and patients with neuromuscular diseases due to the risk of the "venting effect" (pooling of secretions), which impairs the clearance of sputum from the lower respiratory tract. This effect may require drainage procedures.

Mucolytic agents should not be combined with antitussive medications that impair sputum clearance.

Comments: prescribing medications from the ATX group R05D "Antitussives, excluding combinations with expectorants" to patients with a cough may contribute to sputum stagnation due to the suppression of the cough reflex.

• Steam inhalations for the treatment of ARVI in children are not recommended due to the risk of burns [100] and the lack of convincing evidence of their benefit [101]. The WHO does not recommend using steam inhalations for the treatment of cough and ARVI in children [102, 210, 211].

GCR ALEL 1Grade of Recommendations — A (Level of Evidence — 1).

Comments: dehydration may increase the risk of side effects from antipyretic drugs.

For the dehydration assessment scale, see Appendix G1.

Fractional administration of oral rehydration salts (ATX group A07CA) is prescribed according to clinical indications. For younger children, rehydration is administered in amounts of 0.5–1 teaspoonful; for older children, in small sips [33].

Children with signs of mild dehydration (irritability, thirst) are indicated for the administration of oral rehydration salts (ATX group A07CA) for dehydration syndrome [271].

Preparations with the following characteristics are used:

• reduced Na+ osmolarity — 50–60 mmol/L;

• glucose osmolarity — less than 90 mmol/L;

• total solution osmolarity — less than 245 mmol/L and not less than 200 mmol/L [105].

Administration of a hypo-osmolar solution helps replenish electrolytes and water lost by the body due to dehydration associated with febrile states in ARVI [33, 106].

Parents should be informed about the importance of oral rehydration of the child using special oral rehydration salts (ATX group A07CA) (rather than dextrose** solution) when fever exceeds 38°C [33].

If oral fluid intake is not possible, or in cases of severe dehydration, parenteral rehydration using solutions affecting water-electrolyte balance (balanced ionic solutions) may be indicated. To prevent dehydration, enteral fluid intake is indicated in the volume of age-related requirements. The physiological requirement in children according to the Holliday-Segar formula is:

• up to 10 kg: 100 mL/kg/day;

• from 10 to 20 kg: 1000 mL + 50 mL for each kg of body weight over 10 kg;

• over 20 kg: 1500 mL + 20 mL for each kg of body weight over 20 kg. For children over 40 kg: 1500 mL/m² of body surface area.

In respiratory failure and/or ARDS, it is advisable to limit fluid intake to 50% of the physiological requirement.

If gastrointestinal function is not impaired, the majority of fluids should be administered enterally (orally or via a tube).

Efforts should be made to achieve "zero fluid balance," meaning the volume of diuresis (or other losses) should be approximately equal to the volume of fluid administered over 24 hours.

In hemodynamically stable patients, fluid restriction is necessary, titrated starting from 50% of the total calculated daily requirement.

In patients with fluid retention, the administration of "loop" diuretics is justified [334]. Hyperhydration is life-threatening for patients. Optimal solutions for infusion therapy are those affecting water-electrolyte balance (balanced iso-osmolar iso-ionic crystalloid solutions).

• In the presence of signs of severe hypovolemia, fluid bolus therapy is indicated using solutions affecting electrolyte balance (balanced crystalloid solution at a volume of 20 mL/kg over 30–60 minutes, with effect assessment. Repeat up to 3 times if necessary. The effect of therapy must be evaluated after each bolus [335].

The main goal of infusion therapy is to maintain an adequate circulating blood volume and normalize perfusion.

Criteria for adequate tissue perfusion include:

- Capillary refill time ≤ 2 s;

- Satisfactory pulse volume on peripheral and major arteries;

- Warm extremities;

- Hourly urine output > 1 mL/kg/h;

- Blood pressure values correspond to the age norm (absence of arterial hypotension and hypertension);

- Normal blood glucose concentration values;

- Normal blood ionized calcium concentration values.

3.1.2 Etiotropic (Antiviral) and Immunomodulatory Therapy

The risk of adverse events from pathogen-targeted therapy outweighs the potential benefit in mild infections; widespread use fosters resistance (proven for influenza viruses and neuraminidase inhibitors) [107, 274].

A neuraminidase inhibitor may be prescribed:

o Oseltamivir** (dosages per instructions)

or

o Zanamivir for children aged 5 years and older (dosages per instructions) [61, 62, 107, 272].

GPP BLoE 1Level of Evidence/Grade of Recommendation – B (level of evidence - 1).

Comments: these drugs are ineffective against other viruses that do not contain neuraminidase. Caution should be exercised when deciding to use neuraminidase inhibitors, taking into account the risk-benefit balance.

Postmarketing use of oseltamivir** has shown an increased risk of nausea, vomiting, and psychiatric disorders in adults, and vomiting in children. Oseltamivir** did not show a protective effect in reducing mortality among patients with 2009A / H1N1 influenza [272].

Use of zanamivir may cause bronchospasm and other allergic reactions [273]. As a rule, oseltamivir** is more commonly used among neuraminidase inhibitors in children.

Oseltamivir** and zanamivir should not be used for mild to moderate clinical signs of influenza in patients without premorbid conditions and risk factors for complications, nor for post-exposure prophylaxis of influenza [62].

For details, see the clinical guidelines for "Influenza" (age category – children).

Or

Drug from the group "Other antiviral drugs" (polymerase acidic endonuclease inhibitor):

o Baloxavir marboxil in patients with moderate influenza, including patients with influenza from risk groups [109, 110, 111, 112].

GCR ALEL 2Grade of Recommendation — A (Level of Evidence - 2).

Comments: baloxavir marboxil (ATX code J05AX25, ATX group "J05AX Other antiviral drugs") is active against influenza viruses A, B, C, and D. It may be prescribed to children with a body weight of 20 kg or more according to the instructions for use.

Various antiviral and immunomodulatory drugs widely used in the Russian Federation lack a sufficient body of evidence for efficacy and safety. According to most publications, efficacy is manifested by a reduction in time to feeling better within one day [14, 15, 118, 119, 120].

The necessity of using these drugs should be considered by eliminating excessive prescriptions, polypharmacy, and drug interactions, after evaluating the expected benefit and the risk of adverse events [121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151 et al.].

Caution must be exercised, and they should not be used routinely. Drug interactions for most of these agents have not been established.

Reference information is provided in Appendix A3.5.

3.1.3 Antimicrobial Therapy

Comments: antibacterial therapy in uncomplicated viral infection not only fails to prevent bacterial superinfection but actually promotes its development due to suppression of the normal pneumotropic microbiota.

Systemic antibacterial drugs may be indicated for children with chronic conditions affecting the bronchopulmonary system (e.g., cystic fibrosis) or immunodeficiencies who are at risk for exacerbation of a bacterial process; the choice of drug in these cases is usually predetermined by the microbiological characteristics of the sputum/bronchoalveolar lavage fluid.

3.2 Surgical Treatment

Not required.

3.3 Other Treatment

3.3.1 Phytotherapy

Despite the widespread use of herbal remedies classified as expectorants (apart from combinations with antitussives), the evidence confirming their efficacy in children with ARVI and acute tracheitis is not high—both due to the lack of well-designed RCTs and comparative efficacy observations, and because of only sporadic data on standardized approaches to substance manufacturing.

3.3.2 Diet for ARVI

No separate studies on nutrition during ARVI have been conducted; most experts, physicians, and researchers agree that children should not be forced to eat during fever ("feed to appetite" is considered optimal) [65].

Fluid intake should be rational—the benefit of forced high fluid intake is questionable, whereas elevated antidiuretic hormone secretion during illness, conversely, promotes fluid retention [65, 195].

Based on the assessment of the degree of dehydration (section 2.2, Appendix G1), the need for water-electrolyte balance correction is determined—oral or parenteral rehydration may be performed according to indications (section 3.1).

Parents should be informed about the importance of oral rehydration of the child with special glucose-electrolyte solutions (!! not dextrose solution**) when fever exceeds 38°C.

Non-pharmacological Interventions

Understanding ARVI as a mild, self-limiting condition that in most cases does not require pharmacotherapy can spare the patient from both excessive diagnostic interventions and unnecessary medication prescriptions.

Of particular interest are the results of modern studies on the use of various non-pharmaceutical, "home" remedies. Thus, it has been shown that the use of honey/lemon/herbal teas for treating ARVI symptoms can be effective and eliminate the need for prescribing pharmaceuticals. In patients with no history of allergies, these remedies can be considered as a safe alternative for the symptomatic treatment of ARVI [159, 160, 161, 162].

4. Medical Rehabilitation and Sanatorium-Resort Treatment

In most cases—not required.

Acute infectious diseases are a contraindication for sanatorium-resort treatment.

Comments: there are publications indicating that cortisol release during stress can negatively affect the immune response and increase susceptibility to respiratory infections [168].

The detrimental effects of tobacco smoke, combustion products [169], sleep deprivation [170, 171, 172], and nutritional deficiencies [173, 174, 175] on the frequency of respiratory infections have been described.

The negative role of general body cooling [173, 174, 175] is highly probable and should be avoided.

At the same time, there are reports of a positive effect of moderate physical activity (reduction in the frequency and severity of respiratory infections), but currently no conclusive evidence has been obtained, and further research is required [176, 177].

If complications develop or comorbid conditions exacerbate, rehabilitation measures are prescribed by relevant specialist physicians.

5. Prevention and Dispensary Observation

Preventive measures are aimed at early and active diagnosis of ARVI and potential complications, as well as the isolation of patients from organized groups.

5.1 Prevention of Acute Infections

Comments: physical measures to prevent the spread of respiratory viruses between people include:

• frequent hand washing;

• avoiding touching eyes, nose, or mouth;

• sneezing or coughing into the elbow;

• wiping surfaces with a disinfectant;

• wearing personal protective equipment — masks, eye protection, gloves, and gowns;

• avoiding contact with other people (isolation or quarantine);

• maintaining a certain distance from other people (social distancing);

• screening people entering the country for signs of infection [214].

Nonspecific measures for preventing the transmission of ARVI, including by patients/legal representatives, include adherence to the 3W and 3A rules.

3W Rule:

• Wash hands with soap and water at at least 30^°C as often as possible;

• Wear a mask to cover your mouth and nose;

• Watch your distance, keeping at least 1.5 m from other people.

3A Rule — avoid:

• Areas poorly ventilated;

• Areas or spaces with large crowds of people;

• Approaching people who are talking or singing too closely.

The prevention of most viral infections remains nonspecific today, as vaccines against all respiratory viruses are not yet available.

Comments: it has been proven that vaccinating children against influenza and pneumococcal infection reduces the risk of acute otitis media in children, i.e., decreases the likelihood of a complicated course of ARVI [217, 218].

For children who have recovered from ARVI, preventive vaccination is generally administered 1 week after recovery. In an unfavorable epidemiological situation, the potential benefit of vaccination outweighs a wait-and-see approach. Vaccinations may be administered earlier.

Comments: according to the instructions for medical use, the administration of palivizumab** is limited to 6 months of age, but in cases of profound prematurity, it is advisable to consider extending the administration period up to 12 months of life. These administration timelines are recommended in many international consensus documents.

Comments: it should be borne in mind that the use of cardiopulmonary bypass or extracorporeal membrane oxygenation results in a decrease in plasma palivizumab** concentrations by more than 50%.

Comments: the decision to administer palivizumab** passive immunization to patients with the aforementioned diseases and conditions is made by a medical board based on the assessment of the risk of developing severe RSV infection.

Comments: the evidence supporting the efficacy of the drug for this purpose is of low quality.

Prevention of Recurrent Infections

A special group consists of children with recurrent respiratory infections (formerly referred to as frequently ill children). The inclusion criterion for this group is an increased frequency of acute respiratory viral infection (ARVI) episodes over the course of 1 year.

The causes of recurrent respiratory infections may include characteristics of the infectious agent, environmental factors, psychosomatics, passive smoking, atopy, and chronic diseases (e.g., cystic fibrosis, gastroesophageal reflux disease, congenital heart defects, chronic aspiration, immunodeficiency states, etc.) [242, 243, 244].

Thus, it is well known that the immune response in individuals with allergic diseases develops predominantly via a Th2 pathway with lower interferon production, predominant synthesis of class E immunoglobulins, and insufficient IgG synthesis, which contributes to a higher incidence of ARVI. Some children with recurrent ARVI exhibit transient deviations in immune status parameters [245]. The aforementioned conditions are regarded as transitory functional instability of the immunity, leading to a decrease in anti-infective resistance in these children. However, based on the results of immune status studies, targeted selection of immunocorrective therapy is practically unfeasible.

In recent years, the possibility of using various drugs with immunomodulating/immunostimulating activity to enhance protection against ARVI has been investigated [167].

Comments: these drugs may reduce the incidence of ARVI in children with recurrent upper respiratory tract infections, although the results of available observations are heterogeneous [246].

Bacterial lysates possess the largest body of evidence — both regarding ARVI and ENT diseases, as well as exacerbations of chronic pathologies, including asthma [247, 248].

Before deciding to prescribe these and other medications, potential risks and expected benefits should be weighed.

- ascorbic acid** [213],

Level of Recommendation CLevel of Evidence 5Level of recommendation – C (level of reliability of evidence - 5),

- homeopathic remedies [254, 255, 259].

Level of Recommendation CLevel of Evidence 2Level of recommendation – C (level of reliability of evidence - 2).

Comments: the efficacy of certain vitamins, antidiarrheal microorganisms/dietary supplements containing probiotics, etc., as well as complementary and alternative medicine for the prevention of ARVI continues to be studied. Unfortunately, the actual benefits described in publications raise doubts about the appropriateness of prescription and require confirmation by additional studies [167].

Comments: in studies, a low vitamin D level was associated with an increased incidence of respiratory infections, in particular, influenza. Supplementation with drugs from the "Vitamin D and analogues" group significantly reduced the incidence of ARVI both among nominally healthy children and among patients with immunodeficiency [260].

Comments: according to systematic reviews and meta-analyses, the efficacy of L. rhamnosus GG compared to placebo has been demonstrated by the following criteria: reduction in the risk of respiratory infections, decrease in the frequency of respiratory infections, average duration of a respiratory infection episode, and frequency of systemic antibacterial drug prescriptions for upper respiratory tract infections. The probiotic strain S. salivarius K12 is effective in reducing the frequency of respiratory infections (rhinitis, pharyngitis, laryngitis, acute otitis media), including recurrent ones [269].

6. Organization of Medical Care

Children with ARVI may be provided with medical care, if necessary, in any settings and forms stipulated by Russian legislation.

A child with ARVI is usually monitored in outpatient settings by a pediatrician/district pediatrician/general practitioner (family doctor) or an infectious disease physician. General regimen or, if necessary, semi-bed rest with a quick transition to general regimen after temperature reduction. A repeat examination is necessary if the fever persists for more than 3 days or if the condition worsens.

In the case of a complicated course of ARVI, or if outpatient treatment is unsuccessful or cannot be implemented in an outpatient setting, the issue of hospitalizing the patient is considered.

In the case of prolonged febrile fever, severe complications of ARVI, as well as for epidemic indications, treatment is carried out in inpatient settings, if possible — in a boxed department/ward/infectious diseases department [8, 55, 270].

Must be hospitalized in a hospital:

- children under 3 months of age with febrile fever due to the high risk of developing a severe bacterial infection [271];

- children of any age in the presence of any of the following symptoms (main danger signs):

• inability/refusal to drink/breastfeed;

• drowsiness, lethargy, unresponsiveness to contact (pay attention to the lack of eye contact) or unconsciousness, or marked agitation;

• symptoms of respiratory distress (dyspnea, tachypnea, chest retractions during breathing, use of accessory muscles in the act of breathing, grunting/moaning respiration, apnea);

• central cyanosis;

• signs of heart failure;

• severe dehydration [271];

• prolonged febrile fever (more than 4–5 days), refractory to antipyretic therapy;

• hemorrhagic syndrome (epistaxis, streaks of blood in cough, hemorrhagic rash).

- children with complex febrile seizures (lasting more than 15 minutes and/or recurring more than once within 24 hours) are hospitalized for the entire period of fever;

- children with febrile fever and suspected severe bacterial infection (BUT hypothermia may also occur!) who have the following concomitant symptoms: lethargy, drowsiness; refusal to eat and drink; decreased urination; hemorrhagic skin rash; vomiting;

- children with signs of respiratory failure who have any of the following symptoms: grunting respiration, nasal flaring during breathing, head bobbing (head movements synchronized with inspiration); respiratory rate in a child under 2 months > 60 per minute, in a child aged 2–11 months > 50 per minute, in a child older than 1 year > 40 per minute; lower chest wall retraction during breathing; blood oxygen saturation < 95% while breathing room air [271].

- children with comorbid pathology in the presence of a risk of exacerbation/decompensation:

o immunodeficiency state, including against the background of immunosuppressive therapy;

o oncological and oncohematological diseases;

o diseases with blood coagulation disorders (hemophilia, von Willebrand disease, thrombocytopenia);

o congenital and acquired heart defects and diseases, including rhythm disorders;

o cardiomyopathy, pulmonary hypertension;

o congenital and acquired chronic lung diseases (bronchopulmonary dysplasia, bronchial asthma, etc.);

o CNS diseases (organic CNS lesions, cerebral palsy, epilepsy, etc.);

o endocrine system diseases (e.g., type I diabetes mellitus);

o chronic progressive hepatobiliary system diseases (chronic hepatitis, liver cirrhosis and fibrosis, cholangitis);

o chronic kidney diseases (glomerulonephritis, pyelonephritis, tubulopathies, chronic kidney disease);

o chronic diseases of the digestive system (Crohn's disease, ulcerative colitis, peptic ulcer disease, etc.);

o other chronic diseases if there is a risk of exacerbation/decompensation.

- hospitalization based on epidemiological indications (e.g., children from 24-hour social care facilities, temporary accommodation centers, socially disadvantaged families, or unfavorable social and living conditions when isolation and treatment outside a medical organization are not possible).

The average length of hospital stay may range from 3 to 7 days, depending on the nosological form of the complication and the severity of the general condition.

Hospitalization of children with rhinitis/rhinopharyngitis, laryngitis, or tracheitis without concomitant dangerous signs is impractical.

Children with simple febrile seizures (lasting up to 15 minutes, occurring once within 24 hours) that have stopped by the time of admission to the hospital do not always require hospitalization, but the child must be examined by a physician to rule out neuroinfection and other causes of seizures—the need for hospitalization is determined on an individual basis.

During hospitalization, the severity of symptoms should be monitored, including by nursing staff [345].

7. Additional Information

7.1 Complications

ARVI complications are uncommon. As a rule, they are associated with secondary bacterial infection.

Complications [8, 14, 339, 340, 341].

Acute sinusitis. This complication is usually of bacterial etiology (inflammation of the paranasal sinuses—maxillary sinusitis, frontal sinusitis, sphenoid sinusitis, ethmoid sinusitis). Bacterial sinusitis should be suspected if nasal congestion persists for a prolonged period (more than 7 days), a second "wave" of body temperature elevation occurs, along with a feeling of heaviness in the head and headache (see clinical guidelines for "Acute Sinusitis") [37, 51].

Acute otitis media. This complication can be of either viral or bacterial etiology; acute otitis media manifests as constant or throbbing (shooting) ear pain, and tenderness in the mastoid area may be observed. Catarrhal otitis media is a frequent complication of respiratory viral infections, especially in the presence of rhinitis or in patients with RSV infection (see clinical guidelines for "Acute Otitis Media").

There is a risk of developing acute otitis media against the background of nasopharyngitis, especially in young children, usually on the 2nd–5th days of illness. Its incidence can reach 20–40%, although far from everyone develops purulent otitis media requiring antibacterial therapy [27, 282].

Acute bronchitis. May develop as a complication of ARVI; manifests as a prolonged productive cough (see clinical guidelines for "Bronchitis").

Pneumonia. In some cases, it can become a complication of ARVI. A characteristic sign of community-acquired pneumonia, caused by both typical and atypical pathogens, is a persistent temperature of ≥ 38.0°C for more than 3 days, whereas in ARVI such temperature occurs in only 18% of patients (in influenza, adenovirus, and enterovirus infections) (see clinical guidelines for "Community-Acquired Pneumonia" in children).

Against the background of influenza, the incidence of viral and bacterial pneumonia (most commonly caused by Streptococcus pneumoniae) can reach 12% of children who have contracted the viral infection [61].

Bacteremia complicates the course of ARVI in an average of 1% of cases in RSV infection and 6.5% of cases in enterovirus infections [26].

Respiratory infection can act as a trigger for the exacerbation of chronic diseases, most commonly bronchial asthma and urinary tract infections.

7.2 Outcomes and Prognosis

As noted above, ARVI, in the absence of bacterial complications, is usually short-lived, although symptoms such as nasal discharge and cough may persist for 1–2 weeks. The opinion that recurrent ARVI, especially frequent episodes, is a manifestation of or leads to the development of "secondary immunodeficiency" is groundless.

Data indicating that acute respiratory infections "progress" into chronic diseases (bronchial asthma, bronchiectasis, etc.) are also unconfirmed.

Criteria for Evaluating the Quality of Medical Care

Table 1.

Criteria for assessing the quality of primary health care provided to children with acute viral respiratory infection (ICD-10 codes: J00, J04.1, J06, J39.9, B34.0, B34.2)

Table 2.

Criteria for assessing the quality of specialized medical care provided to children with acute viral respiratory infection (ICD-10 codes: J00, J04.1, J06, J39.9, B34.0, B34.2)

References

Appendix A1. Working Group Composition

Bagnenko S.F. — Academician of the RAS, Professor, MD, DSc, Chairman of the Board of the Russian Society of Ambulance Physicians, Chief freelance specialist in emergency medical care of the Russian Ministry of Health.

Baranov A.A. — Academician of the RAS, Professor, MD, DSc, Honorary President of the Union of Pediatrists of Russia, Advisor to the Head of the Research Institute of Pediatrics and Child Health of the National Medical Research Center No. 2 of the Petrovsky National Research Centre of Surgery, Professor of the Department of Pediatrics and Pediatric Rheumatology at the Sechenov First Moscow State Medical University of the Russian Ministry of Health (Sechenov University), Chief freelance pediatric specialist of the Russian Ministry of Health.

Alekseeva A.A. — PhD in Medicine, Deputy Head of the Consultative and Diagnostic Center for Children — Pediatrician, Head of the Multidisciplinary Pediatric Day Hospital — Allergist-Immunologist, Leading Researcher at the Department of Clinical Immunology and Allergology, Research Institute of Pediatrics and Child Health, National Medical Research Center No. 2 of the Petrovsky National Research Centre of Surgery, Member of the Union of Pediatrists of Russia.

Andreeva I.V. — Senior Researcher, Associate Professor, Institute of Antimicrobial Chemotherapy, Smolensk State Medical University of the Russian Ministry of Health, Member of ISAC (MACMAH).

Andzhel A.E. — Deputy Chief Medical Officer for Clinical Work, Morozov Children's City Clinical Hospital of the Moscow Healthcare Department, Member of the Union of Pediatrists of Russia.

Bakradze M.D. — MD, DSc, Chief Researcher, National Medical Research Center for Children's Health of the Russian Ministry of Health, Head of the Department of Childhood Diseases at the Faculty of Advanced Medical Training, Moscow Regional Research and Clinical Institute (MONIKI) named after M.F. Vladimirsky, Member of the Union of Pediatrists of Russia.

Bulgakova V.A. — MD, DSc, Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Head of the Department of Scientific and Information Development, Research Institute of Pediatrics and Child Health, National Medical Research Center No. 2 of the Petrovsky National Research Centre of Surgery, Member of the Union of Pediatrists of Russia, Moscow.

Burykina V.V. — Emergency Medicine Physician, Assistant at the Department of Emergency Medical Care and Injury Surgery, Pavlov First Saint Petersburg State Medical University of the Russian Ministry of Health.

Vishneva E.A. — MD, Professor of the Russian Academy of Sciences, Chief freelance pediatric specialist in allergology and immunology at the Moscow Healthcare Department; Deputy Director for Clinical and Research Work, Kommunarka Moscow Multidisciplinary Clinical Center; Allergist-Immunologist at Kommunarka MMC of the Moscow Healthcare Department; Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia, Member of the Russian Association of Allergologists and Clinical Immunologists.

Vlasova A.V. — MD, Head of the Clinical Pharmacology Department, Morozov Children's City Clinical Hospital of the Moscow Healthcare Department, Associate Professor at the Academician B.E. Votchal Department of Clinical Pharmacology and Therapy, RMACPE.

Gordeva O.B. — PhD, Head of the Department of Scientific Foundations of Hemostasis, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Associate Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Ermolenko K.D. — MD, Deputy General Director for Scientific and Educational Activities, Federal Scientific and Clinical Center for Infectious Diseases of the Federal Medical-Biological Agency.

Ivanov A.A. — Expert Analyst, Department for the Implementation of Functions of the National Medical Research Center for Pediatrics, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Ivardava M.I. — PhD, Head of the General Pediatrics Department, Pediatrician, Head of the Department for the Development of Scientific Approaches to the Management of Children with Motor Disorders, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Member of the Union of Pediatrists of Russia.

Kaitukova E.V. — PhD, Deputy Head for Medical Operations — Head of the Consultative and Diagnostic Center for Children, Gastroenterologist, Leading Research Fellow at the Department of Orphan Diseases and Prevention of Disabling Conditions, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Associate Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Karaseva M.S. — Junior Research Fellow, Pediatrician, Scientific and Practical Center for Pediatric Psychoneurology of the Moscow Healthcare Department, Member of the Union of Pediatrists of Russia.

Kozlov R.S. — Corresponding Member of the Russian Academy of Sciences, Professor, MD, Rector of Smolensk State Medical University of the Russian Ministry of Health, Chief freelance specialist of the Russian Ministry of Health in clinical microbiology and antimicrobial resistance, President of MACMAH.

Kolbin A.S. - MD, Professor, Head of the Department of Clinical Pharmacology and Evidence-Based Medicine, Pavlov First Saint Petersburg State Medical University.

Komarova E.V. — MD, Deputy Head for Expertise of Innovative Treatment and Rehabilitation Methods, Gastroenterologist, Chief Research Fellow at the Department of Orphan Diseases and Prevention of Disabling Conditions, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Konovalov I.V. — PhD, Deputy Director of the Center for Educational Programs Implementation, Institute of Motherhood and Childhood, Associate Professor at the Department of Infectious Diseases in Children, Institute of Motherhood and Childhood, Expert Analyst, Department for the Implementation of Functions of the National Medical Research Center, Pirogov Russian National Research Medical University (Pirogov University).

Kryuchko D.S. — MD, Head of the Department of Translational Medicine and Innovative Technologies, Federal Medical-Biological Agency.

Kulichenko T.V. — MD, Professor of the Russian Academy of Sciences, Head of the National Medical Research Center, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, World Health Organization Expert, Member of the Union of Pediatrists of Russia.

Lashkova Yu.S. — PhD, Head of the Pediatric Diagnostic Department, Russian Children's Clinical Hospital — branch of Pirogov Russian National Research Medical University of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Levina Yu.G. — MD, Associate Professor, Head of the Department of Clinical Immunology and Allergology, Allergist-Immunologist, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery of the Russian Ministry of Science and Higher Education, Associate Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Mayansky N.A. — MD, Professor of the Russian Academy of Sciences, Head of the Center for Laboratory Diagnostics, Russian Children's Clinical Hospital of Pirogov Russian National Research Medical University.

Namazova-Baranova L.S. — Academician of the Russian Academy of Sciences, Professor, MD, President of the Union of Pediatrists of Russia; Past President of EPA/UNEPSA; Head of the Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Head of the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Chief freelance pediatric specialist in preventive medicine of the Russian Ministry of Health.

Novik G.A. — MD, Professor, Head of the Professor I.M. Vorontsov Department of Pediatrics, Faculty of Postgraduate Education, Saint Petersburg State Pediatric Medical University of the Ministry of Health of the Russian Federation.

Ovsyannikov D.Yu. — MD, Professor, Head of the Department of Pediatrics, Peoples' Friendship University of Russia (RUDN University).

Platonova M.M. — PhD, Senior Research Fellow, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Pulmonologist.

Polyakova A.S. — PhD, Member of the Union of Pediatrists of Russia.

Prometnoy D.V. — MD, Head of the Anesthesiology and Intensive Care Center, Russian Children's Clinical Hospital, Expert Analyst, Department for the Implementation of Functions of the National Medical Research Center for Pediatrics, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Pytal A.V. — Anesthesiologist-Intensivist, Russian Children's Clinical Hospital, Expert Analyst, Department for the Implementation of Functions of the National Medical Research Center for Pediatrics, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Ratnikov V.A. — Acting General Director, Federal Scientific and Clinical Center for Infectious Diseases of the Federal Medical-Biological Agency, Chief freelance specialist of the Federal Medical-Biological Agency in diagnostic radiology, MD, Professor at the Department of Diagnostic Radiology, Scientific, Clinical and Educational Center for Diagnostic Radiology and Nuclear Medicine, Medical Institute, St. Petersburg State University.

Rtishchev A.Yu. — PhD, Associate Professor at the Department of Infectious Diseases in Children, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University), Infectious Diseases Physician, Morozov Children's City Clinical Hospital of the Moscow Healthcare Department, Chief freelance specialist in pediatric infectious diseases in the Central and Southeastern Administrative Districts of Moscow.

Rychkova L.V. — Corresponding Member of the Russian Academy of Sciences, MD, Professor at the Basic Department of Medical Psychology, Director of the Scientific Centre for Family Health and Human Reproduction Problems, Irkutsk State University, Secretary of the Commission of the Scientific Council on Pediatrics, Clinical Medicine Section, Department of Medical Sciences of the Russian Academy of Sciences, President of the Irkutsk Regional Branch of the Union of Pediatrists of Russia.

Rychkova O.A. — MD, Associate Professor, Head of the Department of Infectious Diseases, Allergology and Immunology, Tyumen State Medical University of the Ministry of Health of the Russian Federation, Chief Allergist-Immunologist of the Tyumen Region Healthcare Department.

Selimzyanova L.R. — PhD, Head of the Department of Standardization and Study of Evidence-Based Medicine Fundamentals, Research Institute of Pediatrics and Child Health, Petrovsky National Research Center of Surgery, Associate Professor at the Department of Pediatrics and Pediatric Rheumatology, Sechenov First Moscow State Medical University of the Russian Ministry of Health (Sechenov University), Associate Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Solodovnikova O.N. — PhD, Deputy Chief Medical Officer for Pediatric Care, Kommunarka Moscow Multidisciplinary Clinical Center of the Moscow Healthcare Department, Pediatrician, Infectious Diseases Physician, Associate Professor at the Department of Outpatient and Social Pediatrics, Institute of Professional Education, Pirogov Russian National Research Medical University (Pirogov University).

Starovoytova E.V. — PhD, Expert Analyst, Department for the Implementation of Functions of the National Medical Research Center for Pediatrics, Pirogov Russian National Research Medical University (Pirogov University) of the Russian Ministry of Health, Member of the Union of Pediatrists of Russia.

Sychev D.A. — MD, Professor, Academician of the Russian Academy of Sciences, Scientific Director of the Center for Predictive Genetics, Pharmacogenetics and Personalized Therapy, Petrovsky National Research Center of Surgery.

Tenovskaya T.A. — Deputy Chief Medical Officer for Clinical and Expert Work, Morozov Children's City Clinical Hospital of the Moscow Healthcare Department, Member of the Union of Pediatrists of Russia.

Tyurin I.N. — MD, Honored Doctor of the Russian Federation, Chief Medical Officer of Infectious Clinical Hospital No. 1 of the Moscow Healthcare Department, Department of Anesthesiology and Intensive Care of INOPR, Pirogov Russian National Research Medical University (Pirogov University).

Fedoseenko M.V. — PhD, Head of the Department for the Development of Scientific Approaches to Immunization of Patients with Health Status Deviations and Chronic Diseases, Leading Researcher, Pediatrician at the Research Institute of Pediatrics and Child Health of Petrovsky National Research Centre of Surgery, Associate Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University of the Russian Ministry of Health (Pirogov University), Member of the Union of Pediatricians of Russia.

Kharkin A.V. — MD, Expert Analyst of the Directorate for the Implementation of Functions of the National Medical Research Center for Pediatrics, Member of the Union of Pediatricians of Russia.

Chashchina I.L. — Member of the Union of Pediatricians of Russia.

Chemakina D.S. — PhD, Senior Researcher at the Department of Standardization and Study of Evidence-Based Medicine Foundations, Research Institute of Pediatrics and Child Health of Petrovsky National Research Centre of Surgery, Member of the Union of Pediatricians of Russia.

Efendieva K.E. — PhD, Associate Professor, Deputy Head for International Relations and Educational Activities, Leading Researcher, Allergist-Immunologist at the Research Institute of Pediatrics and Child Health of Petrovsky National Research Centre of Surgery, Associate Professor at the Department of Faculty Pediatrics, Institute of Motherhood and Childhood, Pirogov Russian National Research Medical University of the Russian Ministry of Health (Pirogov University), Member of the Union of Pediatricians of Russia.

Appendix A2. Methodology for Developing Clinical Guidelines

Target audience for these clinical guidelines:

1. pediatricians;

2. general practitioners (family physicians);

3. municipal (district) pediatrician;

4. primary care pediatrician;

5. anesthesiologist-intensivist;

6. emergency physician;

7. bacteriologist;

8. virologist;

9. disinfectologist;

10. health station physician;

11. infectious disease physician;

12. clinical laboratory diagnostics physician;

13. clinical pharmacologist;

14. laboratory physician;

15. neurologist;

16. parasitologist;

17. neonatologist;

18. otorhinolaryngologist;

19. medical prevention physician;

20. medical rehabilitation physician;

21. admitting department physician;

22. epidemiologist;

23. paramedic;

24. medical school students;

25. residents and post-graduate students.

Table 3. Scale for grading levels of evidence (LoE) for diagnostic methods (diagnostic interventions)

Table 4. Scale for grading levels of evidence (LoE) for methods of prevention, treatment, medical rehabilitation, including those based on natural therapeutic factors (preventive, therapeutic, rehabilitation interventions)

Table 5. Scale for grading grades of recommendation (GoR) for methods of prevention, diagnostics, treatment, and medical rehabilitation, including those based on natural therapeutic factors (preventive, therapeutic, rehabilitation interventions)

The mechanism for updating clinical guidelines provides for their systematic revision at least once every three years, as well as upon the emergence of new evidence-based medicine data on the diagnosis, treatment, prevention, and rehabilitation of specific diseases, or in the presence of justified additions/comments to previously approved clinical guidelines, but no more frequently than once every 6 months.

Appendix A3. Reference Materials

Care delivery pathways:

1. Order of the Russian Ministry of Health No. 120n dated February 20, 2026, "On Approval of the Procedure for Providing Medical Care in the Field of Pediatrics."

2. Order of the Ministry of Health and Social Development of the Russian Federation No. 521n dated May 5, 2012, "On Approval of the Procedure for Providing Medical Care to Children with Infectious Diseases."

Criteria for assessing the quality of medical care:

Order of the Russian Ministry of Health No. 203n dated April 14, 2025, "On Approval of Criteria for Assessing the Quality of Medical Care."

Other documents used in the preparation of the clinical guidelines:

1. Federal Law No. 323-FZ of November 21, 2011, "On the Fundamentals of Protecting Public Health in the Russian Federation";

2. Federal Law of the Russian Federation No. 326-FZ of November 29, 2010, "On Compulsory Medical Insurance in the Russian Federation";

3. Federal Law of the Russian Federation No. 52-FZ of March 30, 1999, "On the Sanitary and Epidemiological Welfare of the Population";

4. Resolution of the Chief State Sanitary Doctor of the Russian Federation No. 4 of January 28, 2021, "On Approval of Sanitary Rules and Norms SanPiN 3.3686-21 'Sanitary and Epidemiological Requirements for the Prevention of Infectious Diseases'" (along with "SanPiN 3.3686-21. Sanitary Rules and Norms...") (Registered with the Ministry of Justice of Russia on February 15, 2021, No. 62500);

5. Order of the Ministry of Health of the Russian Federation No. 205n of May 2, 2023, "On Approval of the Nomenclature of Positions of Medical Workers and Pharmaceutical Workers";

6. Order of the Ministry of Health and Social Development of Russia No. 541n of July 23, 2010, "On Approval of the Unified Qualification Handbook of Positions of Managers, Specialists, and Employees, Section 'Qualification Characteristics of Positions of Healthcare Workers'" (Registered with the Ministry of Justice of Russia on August 25, 2010, No. 18247);

7. Federal Law No. 489-FZ of December 25, 2018, "On Amendments to Article 40 of the Federal Law 'On Compulsory Medical Insurance in the Russian Federation' and the Federal Law 'The Fundamentals of Protecting Citizens' Health in the Russian Federation' Regarding Clinical Guidelines";

8. Order of the Ministry of Health of Russia No. 103n of February 28, 2019, "On Approval of the Procedure and Deadlines for the Development of Clinical Guidelines, Their Revision, the Standard Form of Clinical Guidelines, and Requirements for Their Structure, Composition, and Scientific Validity of Information Included in Clinical Guidelines";

9. Order of the Ministry of Health of Russia No. 804n of October 13, 2017, "On Approval of the Nomenclature of Medical Services";

10. Order of the Ministry of Health of the Russian Federation No. 1094n of November 24, 2021, "On Approval of the Procedure for Prescribing Medicinal Products, Prescription Forms for Medicinal Products, the Procedure for Issuing These Forms, Their Accounting and Storage, Prescription Form Forms Containing Designations for Narcotic Drugs or Psychotropic Substances, the Procedure for Their Manufacture, Distribution, Registration, Accounting, and Storage, as well as the Rules for Issuing Prescription Forms, Including in the Form of Electronic Documents";

11. State Register of Medicinal Products: https://grls.rosminzdrav.ru

Appendix A3.1 Explanation of Notes

…^** – a medicinal product included in the List of Vital and Essential Drugs for medical use (Decree of the Government of the Russian Federation No. 3867-r of December 18, 2025, current at the time of approval of the Clinical Guidelines).

Appendix A3.2 Differential Diagnosis of Influenza and Other ARVI

Table 6. Differential diagnosis of influenza, COVID-19, ARVI (letter of the Ministry of Health of Russia dated 02.12.2022 No. 30-4/I/1-20714)

Appendix A3.3 Examples of Diagnosis Formulation

Examples of diagnosis formulation

• Acute nasopharyngitis.

Upon confirmation of the etiological role of a viral agent, the specific finding is included in the diagnosis.

The isolated term "ARVI" should be avoided as a diagnosis, using instead the terms "acute nasopharyngitis", "acute laryngopharyngitis", or "acute pharyngitis" for specification, since ARVI causative agents also cause acute obstructive laryngitis (croup), tonsillopharyngitis, bronchitis, bronchiolitis, which should be indicated in the diagnosis. These syndromes are discussed in detail separately (see Clinical guidelines for the management of children with acute tonsillopharyngitis, bronchitis, acute bronchiolitis, and acute obstructive laryngitis [croup], epiglottitis).  

Appendix A3.4 Clinical and laboratory parameters in systemic inflammatory response syndrome in children

[342] 

Table 7. Age-related changes in respiratory rate, heart rate, leukocyte count, and systolic blood pressure in systemic inflammatory response syndrome in children

Table 8. Laboratory hematological and biochemical markers of systemic inflammatory response syndrome in children and bacterial infection in children over 1 month of age

Appendix A3.5 Antiviral and Immunomodulatory Therapy

- Azoximer bromide** [283, 284, 285].

- Alpha-glutamyl-tryptophan + Ascorbic acid + Bendazol [286].

- Imidazolylethanamide pentandioic acid** [287, 288, 289].

- Inosine pranobex [290, 291, 292, 293, 294].

- Interferon alfa-2b (topical formulations) [178, 179, 180, 181, 182, 183, 184, 185, 186, 187, 188, 189, 190, 191, 295, 296].

- Kagocel — 12 mg tablets [121, 122, 123, 125, 127, 128, 130, 297, 298, 299].

- Meglumine acridoneacetate (tablets) [300, 301, 302, 303, 304].

- Meglumine sodium succinate** (infusion solution) [305].

- Riamilovir [306, 307, 308].

- Tilorone** [309, 310, 311].

- Enisamium iodide [312].

Other medicinal products

Affinity-purified antibodies in microdoses

- Affinity-purified antibodies to interferon-gamma (anaferon) [164, 313].

- Rafamin (affinity-purified antibodies to human interferon-gamma, affinity-purified antibodies to CD4, affinity-purified antibodies to MHC class I β2-microglobulin, affinity-purified antibodies to MHC class II β1-domain) [164, 314].

- Affinity-purified antibodies to interferon-gamma, affinity-purified antibodies to histamine, affinity-purified antibodies to CD4 (ergoferon) [142, 143, 144, 164, 315].

- Euphorbium compositum [316, 317, 318, 319].

Appendix B. Physician Action Algorithms

Appendix B1. Management Algorithm for a Patient with ARVI

Appendix B2. Algorithm for ambulance physician/paramedic management of pre-hospital patients presenting with signs of acute respiratory viral infections (ARVI)

¹ – Pediatric Assessment Triangle (PAT) triage (Appendix G2)

² – ABCDE assessment algorithm (if indicated based on PAT triage results) — a universal tool for the primary assessment of critically ill patients, including children with respiratory infections.

Key rule: «Life-threatening condition → IMMEDIATE intervention → only then proceed to the next step»

A — Airway (Airways) – assessment of upper airway patency, exclusion of foreign bodies.

B — Breathing – respiratory rate, assessment of accessory muscle use, saturation, lung auscultation, presence of cyanosis.

C — Circulation – pulse, capillary refill, skin color and temperature, blood pressure.

D — Disability (Neurological status) (if necessary) – assess the level of consciousness (using any scale: coma scales, e.g., Glasgow (Appendix G3)); pupil size and reaction to light, meningeal signs, muscle tone, blood glucose level in case of depressed consciousness.

E — Exposure (Physical examination) – measurement of body temperature, examination of the body for rashes [343, 344].

³ – see clinical guidelines «Acute obstructive laryngitis [croup], epiglottitis, post-intubation laryngeal edema»

⁴ – MDI – metered-dose inhaler

⁵ – see clinical guidelines «Bronchial asthma»

⁶ – paracetamol** or ibuprofen**; in exceptional cases, including intolerance to paracetamol** or ibuprofen**, or when parenteral antipyretic therapy is necessary and no alternatives are available, after assessing risks and expected benefits, metamizole sodium may be prescribed as a single situational dose (see Section 3)

Appendix C. Patient Information

ARVI (acute respiratory viral infection) is the most common disease in children.

Etiology – various viruses. The disease occurs most frequently in autumn, winter, and early spring.

Transmission of ARVI: most commonly occurs via contact of the nasal mucosa or conjunctiva with hands contaminated through contact with an infected person (e.g., via a handshake) or with virus-contaminated surfaces (rhinoviruses survive on surfaces for up to 24 hours).

Another transmission route is airborne droplets – via inhalation of saliva droplets released during sneezing, coughing, or close contact with an infected person.

Incubation period: in most cases, from 2 to 7 days. Viral shedding by a patient (contagiousness to others) peaks on the 3rd day after infection and drops sharply by the 5th day; low-level viral shedding may persist for up to 2 weeks.

Signs of ARVI: the most frequent manifestation of ARVI in children is nasal congestion and nasal discharge, which may be clear and/or white and/or yellow and/or green (yellow or green nasal discharge is not a sign of secondary bacterial infection!). Fever usually lasts no longer than 3 days, after which body temperature decreases. In certain viral infections (influenza and adenoviral infection), temperature above 38ºC persists longer (up to 5–7 days).

ARVI may also present with: sore throat, cough, eye redness, sneezing.

Assessments: in most cases, additional diagnostic tests are not required for a child with ARVI.

Treatment: ARVI is generally self-limiting, resolves within 10 days, and does not routinely require prescription medications. In mild cases with mild symptoms, non-pharmacological methods may suffice. It should be remembered that fever is a normal reaction to infection that activates the body's innate defense mechanisms; healthcare providers and caregivers should recognize and respond to other danger signs (see below) and assess the general condition, not just the fever.

Fever management: a febrile child should be undressed and gently sponged with water at a temperature of 25–30 °C (physical cooling methods should not be used in «pale» fever accompanied by centralization of circulation manifested by pallor and cold extremities).

Antipyretic drug therapy in healthy children ≥ 3 months of age is justified at temperatures above 38.5 ºC (measured axillary or above 39–39.5 °C measured rectally). For milder fever (38 °C), antipyretics are indicated for infants under 3 months, patients with chronic conditions, and in cases of temperature-related discomfort.

Only paracetamol** or ibuprofen** are used to reduce fever in children.

Alternating or combining antipyretic drugs should be avoided due to the risk of adverse and toxic effects.

A repeat dose should be administered only after observing the recommended dosing interval following a new temperature rise. Regular (scheduled) administration of antipyretics is not recommended.

Acetylsalicylic acid** and nimesulide are not used as antipyretics in children. Metamizole sodium is not used routinely due to the risk of agranulocytosis (suppression of the myeloid blood cell lineage), which can lead to severe complications.

Cough associated with laryngotracheitis and pharyngitis does not require the administration of bronchodilators (drugs for obstructive airway diseases), mucolytics, or inhaled glucocorticoids.

Systemic antibacterial drugs (antibiotics) have no effect on viruses (the primary cause of ARVI). The decision to prescribe systemic antibacterial drugs is considered when a bacterial infection is suspected. Systemic antibacterial drugs must be prescribed by a physician. Indiscriminate use of systemic antibacterial drugs can contribute to the development of antimicrobial resistance and cause complications.

How to prevent ARVI:

A sick child should be kept at home (not sent to kindergarten or school).

Measures preventing the spread of viruses are of paramount importance: thorough hand washing after contact with an infected person.

Wearing masks, cleaning surfaces in the patient's environment, and maintaining regular ventilation are also important.

Annual influenza vaccination starting from 6 months of age reduces the risk of this infection. It has also been proven that vaccination of children against influenza and pneumococcal infection reduces the likelihood of acute otitis media and complicated ARVI courses in children.

There is no reliable evidence that various immunomodulatory therapies reduce respiratory morbidity. The prophylactic efficacy of herbal remedies, ascorbic acid** (vitamin C), and homeopathic preparations has also not been proven.

To reduce the likelihood of contracting ARVI, the 3W and 3H rules should be followed

Rule 3W:

• Wash your hands with soap for at least 30 seconds as often as possible;

• Wear a mask to cover your mouth and nose;

• Watch your distance, keeping at least 1.5 m from other people.

Rule 3A — avoid:

• Areas poorly ventilated;

• Areas or spaces with large crowds of people;

• Approaching people who are talking or singing too closely.

!!! Seek medical attention if:

- the child refuses to drink for a prolonged period;

- you observe behavioral changes: irritability, unusual lethargy with decreased responsiveness to attempts to interact with the child;

- the child has difficulty breathing, noisy breathing, tachypnea, retractions of the intercostal spaces or suprasternal notch (the area located anteriorly between the neck and chest);

- the child has seizures against the background of elevated temperature;

- the child has delirium against the background of elevated temperature;

- elevated body temperature (above 38.4–38.5ºC) persists for more than 3 days;

- nasal congestion persists without improvement for more than 10–14 days, especially if you observe a "second wave" of elevated body temperature and/or worsening of the child's condition;

- the child has ear pain and/or ear discharge;

- the child has a cough lasting more than 10–14 days without improvement.

Appendix G. Assessment Scales, Questionnaires, and Other Evaluation Tools

Appendix D1. Clinical Dehydration Scale (CDS)

Russian title: Clinical Dehydration Scale (CDS).

Original title (if applicable): Clinical Dehydration Scale.

Source (official developer website, validation publication): Goldman RD, Friedman JN, Parkin PC. Validation of the clinical dehydration scale for children with acute gastroenteritis. Pediatrics. 2008 Sep;122(3):545-9. doi: 10.1542/peds.2007-3141, Jauregui J, Nelson D, Choo E, Stearns B, Levine AC, Liebmann O, Shah SP. External validation and comparison of three pediatric clinical dehydration scales. PLoS One. 2014 May 2;9(5):e95739. doi: 10.1371/journal.pone.0095739.

Type (underline): - rating scale.

Purpose: assessment of the degree of dehydration in children.

Content (template):

Key (interpretation): 0 points – no dehydration; 1 to 4 points – mild dehydration; 5–8 points correspond to moderate to severe dehydration.

Notes: none.

Appendix D2. Pediatric Assessment Triangle (PAT)

Russian title: Pediatric Assessment Triangle.

Original title (if applicable): PAT (Pediatric Assessment Triangle).

Source (official developer website, validation publication): Dieckmann R. A., Brownstein D., Gausche-Hill M. The Pediatric Assessment Triangle: a novel approach for the rapid evaluation of children // Pediatric Education for Prehospital Professionals: PEPP Textbook. 2nd ed. Sudbury: Jones & Bartlett Publishers, 2006, Fernández A., Ares M. I., Garcia S., Martinez-Indart L., Mintegi S., Benito J. The validity of the pediatric assessment triangle as the first step in the triage process in a pediatric emergency department // Pediatric Emergency Care. 2017. Vol. 33, No. 4. P. 234–238. https://doi.org/10.1097/PEC.0000000000000717, Ma X., Liu Y., Du M., Ojo O., Huang L., Feng X., et al. The accuracy of the pediatric assessment triangle in assessing triage of critically ill patients in emergency pediatric department // International Emergency Nursing. 2021. Vol. 58. P. 101041. https://doi.org/10.1016/j.ienj.2021.101041

Zhu S., Wu Y., Yu B., Shen B., Fang L., Li B., Xiang L. Clinical validity of the pediatric assessment triangle in a pediatric emergency department // Frontiers in Pediatrics. 2025. Vol. 13. Art. 1435604. https://doi.org/10.3389/fped.2025.1435604

Prehospital Pediatric Assessment Triangle—Real World Data // Prehospital Emergency Care. 2025. Vol. 29, No. 1. (Online first). https://doi.org/10.1080/10903127.2025.2581753

Type (underline): - rating scale.

Purpose: - rapid visual assessment of a child within 30–60 seconds across three domains: appearance, work of breathing, and circulation to skin, which allows determining whether there is a life threat and the priority of care. Used in the prehospital setting, emergency department, and admission department as the basis for triage prior to instrumental examinations.

Content (template):

Key (interpretation):

Level 1-2 – patients in critical condition, medical evacuation to the ICU.

Level 3 – emergency cases, medical evacuation to the hospital, priority treatment.

Level 4 – semi-urgent cases with stable vital signs, do not require medical evacuation to the hospital. If visiting the hospital, treatment is provided on a first-come, first-served basis.

Level 5 – non-urgent patients, outpatient treatment indicated.

Appendix D3. Modified Glasgow Coma Scale for Infants and Children

Russian name: Modified Glasgow Coma Scale for infants and children.

Original name (if any): Modified Glasgow Coma Scale.

Source (official developer website, validation publication): Chaturvedi P, Kishore M. Modified Glasgow Coma Scale to predict mortality in febrile unconscious children. Indian J Pediatr. 2001 Apr;68(4):311-4. doi: 10.1007/BF02721834. PMID: 11370435, Awasthi S, Moin S, Iyer SM, Rehman H. Modified Glasgow Coma Scale to predict mortality in children with acute infections of the central nervous system. Natl Med J India. 1997 Sep-Oct;10(5):214-6. PMID: 9401379.

Type (underline): - rating scale.

Purpose: assessment of coma signs in children.

Content (template):

Modified Glasgow Coma Scale for infants and children

Key (interpretation):

15 points – clear consciousness

13-14 points – obtundation

9-12 points – stupor

4-8 points – coma

Notes: none.