An inactivated virus vaccine that provides active immunization against hepatitis A virus (HAV). Immunization with hepatitis A vaccine induces the formation of anti-HAV antibodies which provide protection against hepatitis A infection. Or A vaccine used to prevent infection with the hepatitis A virus, which causes a serious liver disease. The vaccine is made of a weakened form of the virus that cannot cause disease but causes the body’s immune system to make antibodies that destroy the hepatitis A virus.