General characteristics and taxonomy
Both types of pathogens belong to the Picornaviridae family and are part of the Enterovirus genus. These are compact RNA-containing viruses, each numbering over 30 different serotypes.
The name Coxsackie viruses is geographical in origin — it comes from the American town of the same name where the pathogen was first discovered and isolated.
The abbreviation ECHO stands for Enteric Cytopathogenic Human Orphan. The main fundamental difference between ECHO viruses and the Coxsackie group is that they are non-pathogenic for laboratory animals.
Coxsackie viruses: division into groups A and B
Historically, the classification of Coxsackie viruses is based on their ability to cause specific pathological changes in newborn suckling mice. Depending on the nature of these lesions and the clinical presentation, two main groups are distinguished.
Group A (Coxsackie A) Primarily affects mucous membranes, skin, and skeletal muscles, causing focal necrosis and diffuse myositis. Characteristic clinical forms:
- Herpangina: formation of herpetiform vesicles (blisters) on the posterior pharyngeal wall, accompanied by fever and dysphagia (swallowing disorders).
- Hand, foot and mouth disease (vesicular stomatitis with exanthem).
- Diarrhea is frequently observed in children.
- Skin rashes (exanthem) and poliomyelitis-like neurological diseases are possible.
Group B (Coxsackie B) Characterized by a pronounced tropism for the central nervous system and visceral pathology (internal organ damage), and also causes skeletal muscle necrosis. Typical manifestations:
- Bornholm disease (pleurodynia): agonizing painful chest attacks, febrile syndrome, and pleurisy.
- Myocarditis (severe myocardial damage).
- Neurological pathologies: encephalitis, development of paralysis, and poliomyelitis-like conditions.
ECHO group viruses
Since ECHO viruses are unable to infect laboratory animals, their study and cultivation are carried out exclusively in cell cultures.
The clinical presentation of infections caused by ECHO viruses is quite diverse and may include:
- Acute respiratory viral infections (ARVI).
- Aseptic serous meningitis.
- Diseases mimicking poliomyelitis.
- Various forms of skin rashes.
Microbiological diagnostic methods
Feces and nasopharyngeal swabs (discharges) serve as material for enterovirus detection. When nervous system damage is suspected, especially in the case of ECHO virus infection, cerebrospinal fluid (CSF) is additionally examined.
- Virological method (pathogen isolation):
- For the diagnosis of Coxsackie viruses, the classical method is traditionally used — infection of suckling mice followed by analysis of pathological changes in tissues.
- Coxsackie B viruses, certain group A serotypes, and all ECHO viruses are successfully isolated by infecting cell cultures (e.g., HeLa cells or monkey kidneys).
- Serological method:
- Based on detecting a rise in the titer of specific antibodies in paired blood sera of the patient.
- Identification:
- Determination of a specific serotype is carried out using standardized reactions: HI (hemagglutination inhibition), CF (complement fixation), NT (neutralization test), and ELISA (enzyme-linked immunosorbent assay).
Briefly: answers to topical questions
What cell cultures are used for the virological isolation of Coxsackie B and ECHO viruses?
Primary and continuous cell cultures of human and monkey tissues are used for the virological isolation of Coxsackie B and ECHO viruses.
- Coxsackie B viruses are isolated by infecting HeLa and monkey kidney cell cultures.
- ECHO viruses are isolated using monkey kidney cell culture infection.
Most enteroviruses multiply well in these cultures. Virus indication is accompanied by the development of a cytopathic effect, and under an agar overlay, they form plaques.
What are the mechanisms and routes of transmission of Coxsackie and ECHO viruses in the human population?
Transmission of Coxsackie and ECHO viruses in the human population is carried out via several routes from a sick person or an asymptomatic virus carrier.
- Aerosol mechanism (airborne droplet route) — implemented mainly in the first days of the disease due to massive virus release from the upper respiratory tract during coughing and sneezing.
- Fecal-oral mechanism — caused by the prolonged persistence of the pathogen in the intestine (fecal shedding continues for up to 5 months).
- Vertical mechanism — transplacental transmission of the virus from mother to fetus is possible.
To easily remember the features of the clinical picture of Coxsackie: group "A" stands for Angina (herpangina) and Aphthae (vesicles in hand, foot and mouth disease), while group "B" stands for Body internals (myocarditis, pleurodynia) and pronounced nervous system damage.
Class and exam questions
What is the main microbiological difference between ECHO viruses and Coxsackie viruses?
ECHO group viruses are completely non-pathogenic to laboratory animals. Coxsackie viruses, in contrast, are pathogenic to newborn mice (suckling mice), which is used for their isolation.
What is Bornholm disease and what is the causative agent?
This is epidemic pleurodynia — a disease accompanied by severe paroxysmal chest pain, pleurisy, and fever. It is caused by Coxsackie B viruses.
What specimens are collected from a patient for the diagnosis of ECHO viruses?
Nasopharyngeal discharge, feces, and in the presence of neurological symptoms (e.g., meningitis), cerebrospinal fluid (CSF) are used for examination.
What else to study on this topic
- Pathogenesis of focal necrosis of striated muscle in Coxsackie A infection.
- Differential diagnosis of poliomyelitis-like diseases caused by enteroviruses.
- Mechanisms of myocarditis development in Coxsackie B virus infection.
- Features of enterovirus cultivation on HeLa and monkey kidney cell cultures.
- Principle of performing HI, CF, and NT reactions for serotyping Picornaviridae viruses.
Study the full topic in the «Microbiology» course
This is a summary. The course covers everything tested in classes and exams.
- Complete study guide on "Coxsackie and ECHO viruses" and 4,383 more pages of the subject
- Assignments and quizzes after every topic — just like in a colloquium
- AI tutor answers questions on the topic anytime
- 141 video lectures on the subject
Other topics in the section "Picornaviruses (enteroviruses, poliomyelitis, Coxsackie, ECHO, rhinoviruses, hepatitis A)"
The entire section "Picornaviruses (enteroviruses, poliomyelitis, Coxsackie, ECHO, rhinoviruses, hepatitis A)"Free video lessons: microbiologyShort lessons with study notes — no registration required.
Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.