how long is a hepatitis a immunization good for
Hepatitis A vaccine is a vaccine against the hepatitis A virus. The first successful vaccine against it was invented by Maurice Hilleman at Merck. The vaccine protects against the virus in more than 95% of cases and provides protection from the virus for at least fifteen years.rotection against hepatitis A begins approximately two to four weeks after the initial vaccination. Protection is proven to last at least 15 years and is estimated to last at least 25 years if the full course is administered.