Hepatitis A is a liver disease caused by the hepatitis A virus (HAV).
Clinical features of hepatitis A are similar to those of other types of viral hepatitis. Typical signs and symptoms of hepatitis A include:
- loss of appetite;
- abdominal discomfort;
- jaundice (yellowing discolouration of the skin and sclera of the eyes, dark urine and pale stool).
Not everyone who is infected will have all of the symptoms. Adults have signs and symptoms of illness more often than children, and the severity of disease increases in older age groups. Recovery from symptoms following infection may be slow and may take several weeks or months.
Hepatitis A infection does not cause chronic liver disease and is rarely fatal, but it can cause debilitating symptoms and fulminant hepatitis (acute liver failure), which is associated with high mortality.
Mode of transmission
HAV is transmitted primarily by the faecal-oral route, that is when an uninfected person contacts or ingests objects, food or water that has been contaminated with the faeces of an infected person. The virus can also be transmitted through close physical contact with an infectious person including sexual contact and not limited to anal-oral contact. Hepatitis A outbreaks among men who have sex with men (MSM) have been reported. Waterborne outbreaks, though infrequent, are usually associated with sewage-contaminated or inadequately treated water.
The incubation period of hepatitis A is usually 14 – 28 days.
There is no specific treatment for hepatitis A. Therapy is aimed at maintaining comfort and adequate nutritional balance, including replacement of fluids that are lost from vomiting and diarrhoea.
Improved sanitation, food safety and immunisation are the effective ways to combat hepatitis A. The spread of hepatitis A can be reduced by:
- adequate supplies of safe drinking water;
- food safety practice;
- proper disposal of sewage within communities.
On an individual level, infection risk can be reduced by observing:
- Personal hygiene
- Wash hands properly with liquid soap and water before eating or handling food, and after going to the toilet or changing diapers.
- Food hygiene
- Purchase fresh food from reliable sources. Do not patronise illegal hawkers.
- Drinking water should be from the mains and preferably boiled.
- Cook food thoroughly before consumption. Avoid raw food or undercooked food.
- Clean and wash food thoroughly. Scrub and rinse shellfish in clean water. Remove the viscera if appropriate. All shellfish should be thoroughly cooked before eating.
- Vegetables and fruits to be eaten raw should be cleaned and washed thoroughly with safe drinking water.
- Environmental hygiene
- Keep the premises and kitchen utensils clean.
- Dispose rubbish properly.
Hepatitis A vaccination is a safe and effective means to prevent the infection. Persons who are at increased risk for acquiring hepatitis A and persons with increased risk for severe adverse consequences should discuss with their doctors about hepatitis A vaccination for personal protection. According to Scientific Committee on Vaccine Preventable Diseases, Centre for Health Protection, the following groups are recommended to have hepatitis A vaccination:
- Travellers to endemic areas of hepatitis A
- Persons with clotting factors disorders receiving plasma-derived replacement clotting factors
- Persons with chronic liver diseases