Hepatitis A

Hepatitis A is a liver disease caused by hepatitis A virus (HAV). It is transmitted primarily via the fecal-oral route, that is, the fecal particles from an infected person are introduced into the mouth of another person. The anal-oral sex is an example. The route may also involve one or more intermediate steps such as food or water contaminated by feces from an infected person.

HAV can live outside the body for months, depending on the environmental conditions. HAV is killed by heating to 185^o F (85^o C) for one minute. Adequate chlorination of water, as recommended in the US, kills HAV that may get into the water supply.

Symptoms and Diagnosis

Persons with HAV infection may not have any signs or symptoms of the disease. Older persons are more likely to have symptoms than children.  If symptoms are present, they usually occur abruptly and may include fever, tiredness, loss of appetite, nausea, abdominal discomfort, dark urine, and jaundice (yellowing of the skin and eyes).  Symptoms usually last less than 2 months; a few persons are ill for as long as 6 months. The average incubation period for hepatitis A is 28 days (range: 15-50 days).

Hepatitis A can be diagnosed by blood tests that detect the antibody to HAV (anti-HAV).

Vaccine

The hepatitis A vaccine is available to prevent the disease. It has an excellent safety profile.  No serious adverse events have been attributed definitively to hepatitis A vaccine. Vaccination requires two shots separated by 6-12 months. Protection against hepatitis A begins four weeks after the first shot. With the booster shot, the vaccine can provide protection for up to 20 years.

If you have had hepatitis A in the past, you will never get it again and you cannot transmit the virus to others. Once you recover from hepatitis A you develop antibodies that provide life-long protection from future infections.

Treatment

There is no specific treatment for Hepatitis A. It usually resolves on its own over several weeks. When symptoms are present, sufferers are advised to rest, avoid fatty foods and alcohol.

References:

Centers for Disease Control and Prevention, USA.
Wikipedia