The hepatitis A vaccine is a vaccine used to prevent infection with the hepatitis A virus. Hepatitis A is a contagious liver infection caused by the hepatitis A virus, which is typically spread through contaminated food or water, or close contact with an infected person. The hepatitis A vaccine is highly effective in preventing hepatitis A infection and is recommended for individuals at risk of exposure to the virus, including travelers to areas with high rates of hepatitis A, individuals with certain medical conditions,