Common Diseases

Hepatitis A

Hepatitis A is an acute infectious disease of the liver caused by the hepatitis A virus (Hep A), which is transmitted person-to-person by ingestion of contaminated food or water or through direct contact with an infectious person. The incubation period is between two and six weeks (on average 28 days). In developing countries, and in regions with poor hygiene standards, the incidence of infection with this virus is high. Tens of millions of individuals worldwide are estimated to become infected with Hep A each year. In industrialized countries, such as Australia, the infection is contracted primarily by susceptible young adults, most of whom are infected with the virus during trips to countries with a high incidence of the disease or through contact with an infected person.

Early symptoms of hepatitis A infection can be mistaken for influenza, but some sufferers, especially children, exhibit no symptoms at all. Symptoms typically appear 2 to 6 weeks after the initial infection and usually last less than 2 months, although some people can be ill for as long as 6 months. Some symptoms include: fever, abdominal pain, nausea, appetite loss, jaundice, darkened urine, and clay-coloured faeces.

There is no specific treatment for hepatitis A. Sufferers are advised to rest, avoid fatty foods and alcohol (these may be poorly tolerated for some additional months during the recovery phase and cause minor relapses), eat a well-balanced diet, and stay hydrated.

Hepatitis A can be prevented by vaccination, good hygiene and sanitation. The vaccine, an injection containing inactivated hepatitis A virus, protects against the virus in more than 95% of cases for longer than 20 years. An initial dose provides protection starting two to four weeks after vaccination; the second booster dose, given six to twelve months later, provides protection for over twenty years.