What is Hepatitis A?
Hepatitis A is a virus that has a preference for infecting the liver. Technically it is a small RNA picornavirus with only one serotype.
How is Hepatitis A acquired?
The virus is acquired through consuming contaminated food and water. The contamination is mostly from faeces containing the virus. This virus is rarely acquired through injections and almost never by sexual intercourse. Many young people acquire the infection from the community without becoming ill, or only with very minor symptoms that are mistaken for gastroenteritis or some other virus infection such as the ‘flu. They then develop immunity which protects them for the rest of their lives against further infections of Hepatitis A. This shows up on routine blood screening tests later in their lives.
What are the symptoms?
There is an incubation period between eating the virus in contaminated food and water, and showing clinical symptoms. This period is between 15 and 50 days. In young people, it is frequently very mild and without jaundice (yellowness of the whites of the eyes and the skin) and may not be noticed. However, in elderly people it may become fulminant and even fatal.
Can it be treated?
There is no specific treatment for Hepatitis A. The management is rest and supportive management, much like any viral illness like the common cold or influenza
What is the outcome?
Except for the rare cases where the disease becomes fulminant hepatitis, most cases have an excellent prognosis and full recovery can be expected in about 3 months although rarely there are ups and downs along the way. This virus never causes chronic hepatitis with long term consequences.
Can I vaccinate against it?
If you already have the antibodies in your blood from a previous mild infection, you are protected life long and do not need any vaccination. However in an environment which has become cleaner and more sanitary over the years, most young people in Singapore are now not exposed to the Hepatitis A virus when young and have no immunity. Active vaccination is available for Hepatitis A. It is safe and effective and is recommended for travellers to area where the virus is common, for workers in high risk occupations (e.g. sewage workers). If a patient has another cause for chronic hepatitis, vaccination against Hepatitis A may be given to avoid catching it and ending up with a very severe illness.
