Overview
Hepatitis A is a viral disease that affects the liver. There are several types of viral hepatitis, designated A, B, C, D, and E. Hepatitis A virus is transferred through contact with contaminated food and water or with an infected person. The illness is self-limiting and does not cause a chronic infection.
Introduction
Cases of hepatitis A are reported in New Zealand across all age groups. The majority, but not all, cases report overseas travel immediately prior to symptoms (i.e. during the disease incubation period). A small cluster of cases in 2015 were linked to a batch of imported frozen berries.
Transmission
The hepatitis A virus is transmitted through the faecal-oral route by consumption of contaminated food, including raw shellfish, water or milk or close contact with an infected person.
Certain people are at higher risk from infection, these include:
- Injecting drug users
- People with chronic liver disease or who are at risk of developing chronic liver disease, e.g. people who are hepatitis B or hepatitis C positive, people who misuse alcohol
- Occupational groups exposed to faeces, for example:
- Employees of early childhood services
- Healthcare workers, including cleaners, exposed to faeces
- Sex industry workers
- People who work with sewerage
- Members of the armed forces
- Travellers to moderate and high-risk countries
- Men who have sex with men
Symptoms
Symptoms are usually seen in older children and adults from 15-50 days after infection (on average 28-30 days); young children may not have any symptoms. Symptoms include:
- Fever
- Tiredness
- Nausea
- Loss of appetite
- Abdominal pains
- Dark urine
- Pale coloured faeces
- Jaundice (yellow colour of the skin and eyes), rare in young children
Symptoms usually last for several weeks but less than two months. For 1–2 people in 10 the symptoms will last or come and go for up to six months.
Treatment
There is no specific treatment for hepatitis A infection. Advice from a doctor should be obtained before using medication to relieve pain or fever.
Risks
It is rare for very severe liver problems to develop following hepatitis A but the risk of complications increases with advancing age and is higher in those with pre-existing liver disease.
Unlike other hepatitis viruses, the hepatitis A virus does not cause a chronic infection.
Prevention
Thorough hand-washing using soap and water is necessary to reduce the risk of spread of hepatitis A virus:
- After using the toilet or changing nappies
- Before and after preparing food
- Before eating
Infected people are excluded from early childhood centres, school or work for one week after the start of symptoms or jaundice.
A vaccine is available, but not funded, for people at risk of infection. However, it may be funded for close contacts of hepatitis A cases during an outbreak. It is also recommended for overseas travellers.