Hepatitis A is a liver disease caused by infection with the hepatitis A virus (HAV), and its symptoms include vomiting, diarrhea, and yellowing of eyes. The infection usually goes away on its own without treatment and does not cause long-term (chronic) illness; very rarely, hepatitis A can cause life-threatening liver failure.

Hepatitis A spreads when people eat food or drink water that is contaminated by stool (feces) that has the virus in it. In rare cases the virus is spread by contact with infected blood or blood products.

You can be infected with HAV only once. After that, you have lifelong immunity to the virus and can’t get the disease again.

Hepatitis A virus (HAV) test is a blood test that looks for proteins (antibodies) made by the body in response to the virus that causes hepatitis A. These proteins will be present in your blood if you have a hepatitis A infection now or have had one in the past. It is important to identify the type of hepatitis virus causing the infection to prevent it from spreading and to start the proper treatment.

• IgM anti-HAV antibodies indicate a recent infection with hepatitis A virus. IgM anti-HAV antibodies generally can be detected in the blood as early as 2 weeks after the initial HAV infection. These antibodies disappear from the blood 3 to 12 months after the infection.
• IgG anti-HAV antibodies mean that you have had a hepatitis A viral infection. About 8 to 12 weeks after the initial infection with hepatitis A virus, IgG anti-HAV antibodies appear and remain in the blood for lifelong protection (immunity) against HAV.