Jul 19 2007
Since the transmission of HIV and Hepatitis B virus (HBV) are so similar, individuals infected with one of these viruses are at a significantly increased risk for contracting the other.
As it is not quite clear how patients that don't respond to the HBV vaccine should be managed, new research from the University of Alberta has evaluated the immune response of HBV vaccine given intradermally (into the skin) in HIV-infected individuals who failed to respond to two cycles of HBV vaccine given intramuscularly (into the muscle).
“Because those infected with HIV are at a greater risk for contracting HBV, it is crucial we promote HBV immunizations and continue to put our research efforts into why some HIV patients fail to respond to the vaccine,” said Dr. Stephen Shafran, Professor and Director, Division of Infectious Diseases, at the University of Alberta.
Protecting persons with HIV from contracting the HBV is an important goal. However, people with HIV have a substantially lower success rate with the HBV vaccine compared to the general population.
For this study, researchers were particularly interested in measuring the levels of antibody to hepatitis B produced (called anti-HBs) because the presence of anti-HBs is considered the marker of immunity to HBV infection. Of the patients tested in the cohort, when given the HBV vaccine intradermally rather than intramuscularly, 50 per cent of the subjects successfully produced protective levels of anti-HBs after four doses of vaccine. Conversely, the remaining 50 per cent of patients still did not produce anti-HBs even after given additional doses of HBV vaccine.
“Based on our study we can conclude that administering HBV vaccine intradermally cannot be recommended for HIV-infected adults who did not respond initially to intramuscular administered vaccine,” said Shafran. “Other vaccine strategies, perhaps involving multiple antigens or adjuvants, will need to be investigated.”