Do We Need Hepatitis A Booster Vaccinations?

According to some national authorities and manufacturers' recommendations, a booster dose may be administered 10 years after the primary course. Hepatitis A virus (HAV) vaccines are now widely available, and although current HAV vaccination recommendations vary internationally, most industrialized countries recommend vaccination for at-risk groups such as travelers to developing countries. However, despite this, there is no universal agreement between manufacturers and/or national authorities on how long protection will last, or indeed on whether there will be any need at all in the future for HAV booster vaccinations to provide continued protection. The presence of anti-HAV antibodies following primary vaccination has long been considered a marker of vaccine protection. However, accumulated data from a number of recent studies indicate that long-term protection is dependent on underlying immune memory. Studies have shown that, regardless of conventional antibody responses, immune memory persists and protects against infection. Vaccination programs should aim to achieve a high level of coverage among at-risk individuals, as failure to vaccinate, rather than failure of the vaccine itself, is the main issue facing travelers and their contacts.