Enteroviruses

There are four groups of viruses. These are

1. Coxsachie A (23 Genotype)

 

2. Coxsachie B ( 6 Serotypes)

Causes severe diseases

 

3. Echovirus (28 Serotypes)

 

4. Enterovirus 68-71 (4 serotypes)

Respiratory problems.

Transmission- faecal- oral route, less commonly by respiratory droplet

Common in summer.

Clinical presentations.

Most infected patients are asymptomatic.

The majority symptomatic illness may result in milder symptoms. These are mild fever, rhinitis and pharyngitis.

 

Conjunctivitis

Pain,

Swelling of the eye lid

Keratitis

Some may develop subconjunctival haemorrhage

 

Respiratory infection

Pharyngotonsilitis

Pneumonia

Croup

 

Myocarditis or pericarditis

Most are between 20-39 years old

Palpitation

Chest pain

Arrhythmias

Myocardial infarction

May present with sign of congestive heart failure

Pericardial friction rubs (in pericarditis)

May be complicated by dilated cardiomyopathy

Mortality is high in outbreak.

 

Herpangina

Common in children between 1-5 years

Abrupt onset of fever

Sore throat

Dysphagia

Popular or vesicular rash on the palate

 

Pleurodynia (Bornholm disease)

Nausea and vomiting.

Diarrhoea.

Paroxysmal pain.

Referred pain to the lower ribs or the sternum.

  

Hand Foot Moth Disease (HFMD)

Common in children under the age of 5 years

Fever, sore throat

Papulovesicular rash over the hand, feet, buttock and the mouth

Neurological problems may be seen in some patients

Caused by

 

Aseptic meningitis

One of the commonest causes of aseptic meningitis

May recover within few days

 

Encephalitis

Globular unlike HSV encephalitis

Generalised seizure

Altered state of consciousness

Has good prognosis (unlike HSV)

 

Acute flaccid paralysis

It is becoming one of the main causes of AFP as effective polio vaccine are being used.

 

Hepatitis

Mostly seen in immunocompromised patients with disseminated infection.

 

Chronic infection

Chronic infection is common in patients with agammaglobulinemia.

Dermatomyositis or polymyositis are the main problems that are associated with chronic infection.

In addition it may  cause disseminated illness or death.

 

Long term complications

Diabetic mellitus

Cardiomyopathy

 

Enterovirus in immunocompromised patients

Causes high mortality

Disseminated infection is common.

Treatment may not be effective therefore early detection may be useful to intervene earlier.

Investigation

CBC

CSF- mononucleosis, elevated protein level and normal glucose level

LFT

ECG- Arrhythmia

EEG

CT scan

MRI

 

Tests

Specimens- stool, nasopharyngeal aspirate, blood, CSF and urine.

Culture- cytopathic effect may be observed in 3 to 4 days however with the use of monoclonal viral growth can be detected within 24-48 hours. Neutralisation tests are used to type the viruses. Some viruses do not grow in cell lines therefore animal should be used to isolate and identify them.

Identification of serotype is not important for clinicians

PCR is more sensitive. It is a rapid test and treatment with antibiotics may be discontinued after the enterovirus is identified as a cause of aseptic meningitis.

Serology

Treatment

Symptomatic treatment: Analgesics for the headache or muscular pain

Rehydration

Severe illness may be treated with immunoglobulin but the clinical efficacy is questionable

Pleconaril may be used to treat immunocompromised patients.

Pleconaril -2.5 or 5mg/kg for 7 days

 

Prevention and Infection control

 

Patient isolation.

Hand washing.

 

 

Text Box: Enterovirus in Neonate It causes severe illness in the first 2 weeks of life. It is not associated with congenital abnormality. The virus may transmit while the fetus is in uterus or after delivery.   Clinical Presentations Asymptomatic infection is common. The infection may result in mild infection- fever and mild respiratory infection. Severe infection is characterised by Meningoencephalitis- irritability, vomiting, hypotonia, and bulging of anterior fontanel. Myocarditis is another manifestation (arrhythmia and heart failure). Pneumonitis. Hepatitis- jaundice may be seen in some patients Disseminated intravascular coagulopathy. Death is due to myocarditis or hepatic failure. Sever infection is caused by Group B Coxsackie virus and echovirus 11. Severe infection is seen in babies who are born prematurely or born to mother who have illness at the time of or around delivery.   Investigation CBC LFT ECG CT scan MRI   Tests Specimens- stool, phararyngeal swab, CSF or blood. Culture may take 3-4 days. Some strains may not grow on cell culture. PCR can be done in all specimens. It is more sensitive. Serology-enterovirus IgM may be done.   Treatment Immunoglobulin may be used in neonates with severe illness. Pleconaril may be beneficial although the drug is released only on compassionate ground. It has good bioavailability and safety however it is withdrawn from the market for unknown reason after a license was granted   Prevention Infection control. Washing hands. Patient isolation.