Hepatitis A Post Exposure Prophylaxis

Vaccine as Effective as Immune Globulin for Hepatitis A Postexposure Prophylaxis — ACIP Changes Guidance

For postexposure prophylaxis, hepatitis A vaccine is as effective as immune globulin in preventing transmission, according to reports in NEJM and MMWR.

Researchers randomized 1090 susceptible household or day-care contacts of patients in Kazakhstan to prophylaxis with either hepatitis A vaccine or immune globulin within 2 weeks of exposure. They hypothesized that the effect of the vaccine would be similar to immune globulin. That criterion was met — between 2 and 8 weeks after exposure, vaccine recipients showed a 1.35 relative risk for developing symptomatic infection as compared with those receiving immune globulin. (The confidence interval for the apparent increased risk ranged from 0.70 to 2.67, which an editorialist comments "could signal a true difference between the interventions.)

Consequently, the CDC's Advisory Committee on Immunization Practices has changed its guidelines for postexposure prophylaxis, recommending vaccine for healthy individuals between the ages of 1 and 40. All others should receive immune globulin, if possible.

Physician's First Watch for October 19, 2007