Rotavirus

Notification requirement for rotavirus

Rotavirus is a ‘routine’ notifiable condition and must be notified by pathology services in writing within 5 days of diagnosis. Medical practitioners are not required to notify cases of rotavirus.

Primary school and children’s services centre exclusion for rotavirus

Exclude from school or childcare centre until there has not been a loose bowel motion for 24 hours.

Infectious agent for rotavirus

Rotavirus, predominantly Group A, is the causative agent.

Identification of rotavirus

Clinical features

The disease is characterised by vomiting and watery diarrhoea lasting 3–8 days. Fever and abdominal pain occur frequently.

Diagnosis

Diagnosis may be made by rapid antigen detection of rotavirus in stool specimens. Strains may be further characterised by enzyme immunoassay or reverse transcriptase polymerase chain reaction. Stools for these tests should be collected in the acute phase of illness.

Incubation period of rotavirus

The incubation period is approximately 24–72 hours.

Public health significance and occurrence of rotavirus

Disease usually occurs in unvaccinated infants and young children, particularly those under 2 years of age. Adults can also be infected, although their disease tends to be milder, probably as a result of previous exposure. In temperate climates, rotavirus is more common in winter. Rotavirus gastroenteritis is the leading cause of infant viral gastroenteritis worldwide.

Reservoir of rotavirus

Humans are the reservoir.

Mode of transmission of rotavirus

Rotavirus is transmitted predominantly via the faecal–oral route. Rotavirus has been detected in respiratory secretions. Because the virus is stable in the environment, transmission can occur through ingestion of contaminated water or food, and contact with contaminated surfaces.

Period of communicability of rotavirus

Rotavirus is communicable during the acute stage of disease and while viral shedding continues. Excretion of virus for longer than 30 days has been documented.

Susceptibility and resistance to rotavirus

Immunity after infection is incomplete, but repeat infections tend to be less severe than the original infection. Vaccine efficacy is approximately 70 per cent.

Control measures for rotavirus

Preventive measures

Rotavirus vaccination was added to the National Immunisation Program schedule in July 2007. It is recommended that doses of oral vaccine are given at 2 and 4 months of age, or 2, 4 and 6 months of age, depending on the vaccine used. Completion of the vaccine course with the same brand of vaccine is preferred. Immunisation of older children and adults is not recommended because of lack of safety data in these age groups; therefore, ‘catch-up’ doses are not advised.

Since introduction, the rotavirus vaccination has been associated with a small increase in risk of intussusception, estimated at 14 additional cases in Australia annually. For more information, please refer to the findings of the Therapeutic Goods Administration (TGA) study on the TGA website.

In the unvaccinated, prevention is primarily through good personal, food and home hygiene.

Control of case

Treatment is symptomatic and should focus on maintaining hydration.

Advise the case to maintain strict personal hygiene and handwashing in the home, and to avoid food preparation for others. Healthcare workers and food handlers should be excluded from work, and children from childcare and school, until at least 48 hours after diarrhoea has ceased.

Control of contacts

Determine if others are ill. If so, notify the department so that outbreak investigation and control can occur. Provide advice about strict personal, food and home hygiene.

Control of environment

Rigorous attention to clean-up procedures, and personal and home hygiene is essential to prevent further transmission.

Outbreak measures for rotavirus

An outbreak is defined as two or more related cases of gastroenteritis. The primary aim is to prevent further disease by identifying the source, cleaning contaminated environments and isolating cases.

Special settings

Specific protocols for the management of outbreaks in special settings are available from the department’s Communicable Diseases Section.