HEPATITIS A CAUSES

The time from exposure to HAV and the onset of symptoms ranges from two to seven weeks and averages about a month. The virus is passed in the feces, especially late during this incubation period, before symptoms first appear. Infected persons are most contagious starting a week or so before symptoms develop, and remain so up until the time jaundice (yellowing of the skin) is noted.

Often the first symptoms to appear are fatigue, aching all over, nausea, and a loss of appetite. Those who like drinking coffee and smoking cigarettes may lose their taste for them. Mild fever is common; it seldom is higher than 101°F (38.3°C). The liver often enlarges, causing pain or tenderness in the right upper part of the abdomen. Jaundice then develops, typically lasting seven to ten days. Many patients do not visit the doctor until their skin turns yellow. As many as three out of four children have no symptoms of HAV infection, but about 85% of adults will have symptoms. Besides jaundice, the commonest are abdominal pain, loss of appetite, and feeling generally poorly.

Special situations

An occasional patient with hepatitis A will remain jaundiced for a month, two months or even longer, but eventually the jaundice will pass. Very rarely, a patient will develop such severe hepatitis that the liver fails. HAV infection causes about 100 deaths each year in the United States. In developed countries, a pregnant woman who contracts hepatitis A can be expected to do well although a different form of viral hepatitis (hepatitis E) can cause severe infection in pregnant women. In developing countries, however, the infection may prove fatal, probably because nutrition is not adequate.