1. Home>
2. Specialties>
3. General Medicine>
4. Summary and Comment

MORE SUPPORT FOR INACTIVATED HEPATITIS A VACCINE.

Hepatitis A is a common cause of liver disease that is occasionally fatal. This large double-blind controlled trial provides further evidence that a new inactivated hepatitis A vaccine is safe and effective (see Journal Watch accession number 940506001).

Over 40,000 children in Thailand (aged 1 to 16 years) were randomized to receive either hepatitis A vaccine or a control hepatitis B vaccine at 0, 1, and 12 months. Eighteen months later, each received the alternate vaccine.

There were no serious reactions to the hepatitis A vaccine. During the first phase of the study (before crossover), there were 38 cases of IgM-positive hepatitis A among the controls, but only 2 cases among recipients of hepatitis A vaccine. The hepatitis A vaccine led to protective antibody levels in 94 percent of children before the 1-year booster and 99 percent after the booster; no cases of hepatitis A occurred among recipients after the 1- year booster. Comment: The use of IgM antibodies to mark disease can cause some confusion if the test is performed after immunization. Even so, these data add convincing evidence of the efficacy of the hepatitis A vaccine. We now need a cost- effectiveness analysis to determine whether the vaccine prevents enough illnesses and deaths to justify its expense.

— TH Lee

Published in Journal Watch General Medicine May 10, 1994

Citation(s):

Innis BL et al. Protection against hepatitis A by an inactivated vaccine. JAMA 1994 May 4 271 1328-1334.

• Medline abstract (Free)