Hepatitis A vaccine is a vaccine that prevents hepatitis A. It is effective in around 95% of cases and lasts for at least twenty years and possibly a persons entire life. If given, two doses are recommended beginning after the age of one. It is given by injection into a muscle. The first hepatitis A vaccine was approved in Europe in 1991, and the United States in 1995. It is on the World Health Organizations List of Essential Medicines.The World Health Organization (WHO) recommends universal vaccination in areas where the disease is moderately common. Where the disease is very common, widespread vaccination is not recommended as all people typically develop immunity through infection during childhood. The Centers for Disease Control and Prevention (CDC) recommends vaccinating:

All children aged 12–23 months
Unvaccinated children and adolescents aged 2–18 years
International travelers
Men who have sex with men
People who use injection or non-injection drugs
People who have occupational risk for infection
People who anticipate close contact with an international adoptee
People experiencing homelessness
People with HIV
People with chronic liver disease
Any person wishing to obtain immunityIn addition, a person who has not previously received hepatitis A vaccine and who has direct contact with someone with hepatitis A should get hepatitis A vaccine within two weeks after exposure.Severe side effects are very rare. Pain at the site of injection occurs in about 15% of children and half of adults. Most hepatitis A vaccines contain inactivated virus while a few contain weakened virus.
Inactivated hepatitis A virus produced in MRC-5 cells. Each adult dose contains 1440 ELISA units of viral antigen adsorbed on aluminium hydroxide (0.5 mg Al). The pediatric (child) doses contain half the amount of viral antigen and aluminium. Healive: made by Sinovac. Inactivated hepatitis A virus cultured in human diploid cell, followed by harvest, purification, inactivation, and aluminium adsorption. Each adult dose contains 500 U of viral antigen. The pediatric dose contains 250 U of viral antigen. Vaqta: made by Merck. Inactivated hepatitis A virus produced in MRC-5 cells. An adult dose contains 50 U of antigen adsorbed onto 0.45 mg of aluminium (as aluminium hydroxyphosphate sulfate); a child dose contains half the amounts of antigen and aluminium. Biovac-A: made by Pukang, sold under the brand name Biovac-A in India and under the brand names Mevac-A in Guatemala, Philippines, Bangladesh, Nepal, Uzbekistan and Chile etc. It is a freeze-dried live attenuated hepatitis A vaccine. Hepatitis A virus H2 strain is produced in human diploid cells. A pack of 0.5ml vial of Biovac-A and 0.5ml ampoule of SWFI (sterile water for injection), contains not be less than 6.5 Lg CCID50. Only a single dose is needed. It is recommended by the WHO. Long term persistence research data predicated that sero-conversion remained and antibody titre was not less than 128 IU/ml, 15 years after vaccination. Combination vaccines
Hepatitis A and B vaccine is a vaccine against hepatitis A and hepatitis B. Hepatitis A and typhoid vaccine is a vaccine against hepatitis A and typhoid. References
Further reading
Ramsay M, ed. (2013).