Hepatitis A
Hepatitis A is a serious viral liver disease. An affected person may get jaundice, abdominal pain and diarrhea, or a “flu-like” syndrome with generalized muscle aches, headache, fever/chills, and fatigue. Though suffering may be considerable, the illness is generally self-limiting and resolves in about six weeks, but it can also be fatal in rare cases. The virus can be easily passed by close personal contact, such as between family members, and is also frequently transmitted via contaminated water and food.
Those at risk include individuals living with someone diagnosed with Hepatitis A, staying in an area in which in which there is an outbreak of Hepatitis A, or simply visiting in areas known to have a high incidence of Hepatitis A (such as Africa, Central America, South America, Mexico, and parts of Asia and Eastern Europe).
The primary reason why an adult should get the Hepatitis A vaccine is generally for planned travel to areas in which they would potentially be exposed to the virus, either by contact with infected individuals or contaminated water. This vaccine is also given to children over one year of age as part of their routine vaccination program. Occasionally, there will be outbreaks of Hepatitis A in communities that do not normally have a high incidence of Hepatitis A, and in these instances a community vaccination program is put in place to vaccinate anyone who has not previously had the vaccine. The vaccine is also recommended for those with chronic liver disease, and also for those with blood disorders requiring transfusions of clotting factors, and for men who have sex with men. Hepatitis A can be transmitted from non-human primates, such as chimpanzees, to people so the vaccine is also recommended for those who work in research labs with Hepatitis A infected primates.