Structure & Property

Transmission

Pathogenesis

Clinical findings

Laboratory diagnosis

Treatment

Family: picorna

Genome: single-strand RNA, positive polarity

Size: 22-30nm

Icosahedral nucleocapsid

Nonenveloped

Group A: 23 serotypes

Group B: 6 serotypes

Transmitted primarily by fecal-oral route and respiratory secretions.

Replicate in the oropharynx and intestinal tract.

Humans are only natural hosts.

Immunity is provided by type-specific IgG antibody

Group A viruses infect mainly the skin and mucous membranes.

Group B viruses cause disease in various organs such as the heart, pleura, pancreas and liver.

Both group A and B affect meninges and motor neurons to cause paralysis.

Disseminate via bloodstream to other sites from oropharynx and gut.

Group A:

Herpangina:

- fever

- sore throat

- tender vesicles in oropharynx

Hand-foot-mouth disease:

- vesicular rash on hands and feet.

- ulcerations in mouth

- mainly in children.

Myositis: flaccid paralysis.

Group B:

Bornholm disease:

- fever

- severe chest pain due to inflammation of intercostal muscles.

Myocarditis and pericarditis:

- fever

- chest pain

- signs of congestive failure.

Both groups cause:

- aseptic meningitis

- upper respiratory infections

- minor febrile illnesses

Diagnosis:

- viral isolation in cell culture or suckling mice.

- rise in antibody titer

Isolation:

- feces

- throat swab

Serologic tests are of little value.

Inoculate:

- suckling mice

- group A coxsackieviruse cause flaccid paralysis due to myositis.

- group B coxsackieviruses cause spastic paralysis due to cerebral lesions.

- look out for signs of disease.

ELISA test used to

detect IgM to group B coxsackieviruses.

PCR can be used to detect viral RNA in tissues and CSF.

No antiviral drug therapy or passive immunization is available.