What is the hepatitis A vaccine?
The hepatitis A vaccine is a shot of inactive hepatitis A virus that stimulates the body’s natural immune system. After the vaccine is given, the body makes antibodies that protect a person against the virus. An antibody is a substance found in the blood that is produced in response to a virus invading the body. These antibodies are then stored in the body and will fight off the infection if a person is exposed to the virus in the future.