Page content: Victorian statutory requirement | Infectious agent | Identification | Incubation period | Public health significance & occurrence | Reservoir | Mode of transmission | Period of communicability | Susceptibility & resistance | Control measures | Outbreak measures | Additional sources of information

Victorian statutory requirement

Hepatitis E infection (Group B disease) must be notified in writing within five days of diagnosis.

School exclusion is not applicable.

Infectious agent

Hepatitis E virus (HEV) is the causative agent.

Identification

Clinical features
The clinical course of disease due to HEV is similar to that of hepatitis A. It is a self-limiting disease of adults aged 15–40 years. A high case fatality rate (up to 20%) has been described in pregnant women affected in their third trimester of pregnancy.

Method of diagnosis
Exclusion of other causes of acute hepatitis, particularly hepatitis A is important. HEV may be detected by immune electron microscopy of faeces collected during the acute phase. Serological tests to confirm HEV infection are available through the Victorian Infectious Diseases Reference Laboratory.

Incubation period

The incubation period varies from two weeks to two months. In different epidemics the average incubation period has varied from 26 to 42 days.

Public health significance & occurrence

Sporadic cases and epidemics in adults have occurred in India, areas of the former Soviet Union, some African countries, Mexico and parts of Asia. The disease is not endemic in Australia and cases reported to date have occurred in travellers, with the exception of one patient with no history of overseas travel who was diagnosed in the Northern Territory in 1995.

Reservoir

Humans and some primates act as reservoirs.

Mode of transmission

Hepatitis E is transmitted via contaminated water and possibly through person to person transmission via the faecal-oral route. Evidence of infection in rats and other rodents in some endemic countries suggests other mechanisms of transmission are likely.

Period of communicability

The period of communicability is unknown. HEV has been detected in stools 14 days after the onset of jaundice.

Susceptibility & resistance

Susceptibility is unknown, however disease tends to occur in adults and pregnant women are at particular risk of fulminating disease.

Control measures

Preventive measures
Good personal hygiene is important, particularly after defecation. Travellers to endemic areas should be advised of the risk and avoid ingestion of potentially contaminated water. There are no vaccines against HEV.

Control of case
Treatment is supportive only, particularly the maintenance of hydration.

Food handlers must not work for at least seven days after the onset of jaundice and until well.

It is recommended that health care workers and child care workers remain away from work for at least seven days after the onset of illness and until well. Children should not attend school or child care for seven days after the onset of symtoms.

Control of contacts
Consider the diagnosis in symptomatic contacts. Immunoglobulin prepared from donors in non-endemic countries will not prevent infection or disease.

If the case has worked as a food handler, child care worker or health care worker, surveillance for further cases in the work place should be carried out.

Control of environment
Infected persons should be advised to maintain strict personal hygiene and avoid preparing meals for others unless adequate food safety can be guaranteed.

Food premises, child care centres or health care facilities where a case has worked whilst potentially infective should be requested to complete a clean up in accordance with the Department’s Guidelines for the Investigation of gastrointestinal illness.

Outbreak measures

A case with no history of overseas travel would constitute an outbreak in Victoria. Immediate notification is critical to identify the source and prevent further disease. A detailed epidemiological, environmental and laboratory investigation of common exposures, particularly water, amongst cases is necessary.

Additional sources of information

• Heath, TC, Burrow, JN, Currie, BJ, Bowden, FJ, Fishe,r DA, Demediuk, BH, Locarnini, SA, Anderson, DA 1995, ‘Locally acquired hepatitis E in the Northern Territory of Australia’, Med J Aust., vol. 162, no. 6, pp. 318–9.
• World Health Organization