A study by researchers in Brazil shows that a double dose of a commonly used hepatitis B vaccine is effective in preventing the disease in HIV-positive adults, AIDS Weekly reports. Because both HIV and hepatitis B can be spread through sexual contact and through shared injection-drug paraphernalia--and because some studies have shown treating hepatitis can be difficult in HIV patients--doctors say it is important to vaccinate HIV-positive adults against hepatitis. But previous smaller studies have shown that hepatitis B vaccination has mixed results in HIV patients, with many having poor immune responses to the vaccine.
The current study involved more than 300 HIV patients, 94 of whom received a double dose of hepatitis B vaccine, and the remainder of whom received the standard dose. Nearly half of those given a double dose posted significant increases in hepatitis B-specific antibodies, compared to just 34% of those given a single dose. The study also showed that study subjects with a CD4-cell count below 350 and viral counts above 10,000 copies responded similarly to both double-dose and single-dose vaccination, suggesting a double-dose of vaccine is most effective for patients with stable immune systems and well-controlled HIV infection.
"Based on the results of this study, the best current strategy for hepatitis B vaccination in HIV patients would be to use a double dose as a primary series when the viral load is likely to be low and CD4 greater than or equal to 350, when there is likely to be an adequate immune response," the authors conclude, reports AIDS Weekly.
The full study appears in the journal Vaccine.