Poster Session 42405: The Effectiveness of Hepatitis B Vaccination in HIV-Infected Patients
Hepatitis B vaccination is strongly recommended for people living with HIV (as well as men who have sex with men, health care workers, and injection drug users) who have not already been exposed to this serious virus. Hepatitis B vaccination is usually administered through a series of three injections over a period of six months, and a protective antibody response is typically found in 90% of people completing the vaccine.
This study looked at whether hepatitis B ("Hep B") vaccination is any less effective in patients with HIV, and whether a lower CD4 cell count was associated with increased failure of the vaccine. The study team conducted a retrospective chart review of sixty-seven HIV+ patients who had received the vaccine during the period 1991-1997. The study found that:
- 33 of 67 (49%) of hepatitis B antibody-negative patients completed the vaccination procedure
- 12 of those 33 (36%) developed the Hep B antibodies necessary for an effective immune response against Hep B infection
- 21 of 33, or a startling 64%, did not develop protective antibodies, meaning they remain at risk for Hep B infection
- higher or lower CD4 cell counts were not associated with increased or decreased ability to benefit from vaccination
These results should alert patients and providers to the markedly decreased success rate of Hep B vaccination in HIV-positive patients, the study authors concluded. The researchers urge:
- careful monitoring for vaccine completion
- subsequent Hep B antibody testing to ensure that the vaccine was effective
- continued education about the ways to avoid Hep B transmission
When the vaccine is not effective, re-vaccination should be considered. Finally, the researchers announced that the study will go on to examine the impact of HAART (highly active antiretroviral therapy) on Hep B vaccine effectiveness.