New target groups for vaccination against hepatitis A: homosexual men, injecting drug users and patients with chronic hepatitis.

In countries where the incidence of hepatitis A is low outbreaks of hepatitis A regularly occur among injecting drug users (IDUs) and homosexual men. Obviously these groups are important reservoirs of hepatitis A virus (HAV) and vaccination within these groups should be encouraged. In elderly patients, as well as in patients with chronic liver disease, hepatitis A infection may have a worse prognosis than in young and healthy patients. Also for that reason, patients with chronic liver disease, especially those with chronic hepatitis B and C, are target groups for vaccination against hepatitis A.