P49.06
Background: In 1991, the Global Advisory Group of the Expanded Programme on Immunization recommended that in areas of high HBV endemicity like Sub Saharan Africa (SSA), HBV vaccine be integrated into national immunization programs. Most SSA countries found this roll-out challenging given financial constraints and competing public health priorities. VOICE, a multi-site HIV PrEP trial, was conducted in SSA where high HBV and HIV prevalence rates exist. We aimed to determine the uptake of HBV vaccine and HBV incidence in VOICE.
Methods: A total of 5029 women enrolled into VOICE. Prior HBV exposure was determined at screening (HbsAg, HBsAb). Screening exclusion criteria included HIV infection and HBV infection. Eligible HBsAg negative women were randomized equally to daily oral tenofovir disoproxil fumarate (TDF), TDF/emtricitabine, oral placebo, vaginal tenofovir or placebo gel; all were offered HBV vaccine if not immune (HBsAb negative) or counselling only if immune (HBsAb positive). We summarize HBV testing, vaccination uptake/completion and HBV incidence.
Results: Three thousand six hundred and sixty seven (72.9%) women were not immune at enrolment. Of these, 3648 initiated the vaccination schedule at baseline or sometime during follow-up, yielding a total rate of HBV vaccination uptake of 99.5%. Two thousand nine hundred and eighty eight (81.5%) completed the 3-dose vaccination course as scheduled. A total of 3310 (90.3%) completed ≥3 doses, including cases where the vaccination course was interrupted and later restarted. Among the 3667 who were susceptible at baseline, 5(0.14%) acquired HBV during follow-up, with each HBV infection occurring after receipt of ≥2 doses of vaccine. Of the 5, 1(20%) had HBV and HIV co-infection.
Conclusions: Among VOICE participants, most were susceptible to HBV at enrolment, and uptake of vaccination was high. Despite HIV incidence of 5.7% during the study, the incidence of HBV in women at risk for HIV was low, presumably due to high uptake of effective vaccination.
