Programs that provide inoculations which prevent high risk populations from contracting hepatitis A, an inflammation of the liver caused by the hepatitis A virus (HAV) which can be contracted through contaminated water or food. Included are persons traveling to or working in countries with high rates of infection, sexually active gay/bisexual men, injecting and non-injecting illegal drug users, persons who work with HAV-infected primates in a laboratory setting, persons with chronic liver disease, persons with clotting disorders and, where cost-effective, food handlers. The vaccine is administered in a two-dose regimen separated by a period of six months to a year.