Seroprevalence of HPV vaccine types 6, 11, 16 and 18 in HIV-infected and uninfected women from Brazil.

BACKGROUND: Information on vaccine-type HPV seroprevalence is essential for vaccine strategies; however, limited data are available on past exposure to HPV-quadrivalent vaccine types in HIV-infected woman in Brazil.
OBJECTIVES: To assess the seroprevalence for HPV types 6, 11, 16 and 18 in HIV-infected and uninfected women, from Rio de Janeiro, Brazil and to investigate potential associations with age and pregnancy status. STUDY-
DESIGN: 1100-sera were tested by virus-like particle (VLPs)-based ELISA for antibodies to HPV types 16, 18, 6 and 11. Statistical analysis was carried out by STATA/SE 10.1 and comparisons among HIV-infected and HIV-uninfected women were assessed by Poisson regression models with robust variance.
RESULTS: HPV-6, 11, 16 and 18 seroprevalence was significantly higher among HIV-positive women (29.9%, 8.5%, 56.2% and 38.0%, respectively) compared to HIV-negative women (10.9%, 3.5%, 30.8% and 21.7%, respectively), when adjusted by age and pregnancy status. Overall, 69.4% of HIV-infected and 41.5% of HIV-uninfected women tested positive for any HPV quadrivalent vaccine type. However 4.7% and 1.1%, respectively, tested positive for all HPV vaccine type. In HIV-uninfected women who were pregnant, we found a higher HPV-11 seroprevalence (8.5% vs. 1.5%; P < 0.001) and a lower HPV 16 seroprevalence (22.6% vs. 34.2%; P = 0.010) compared to not pregnant women. HIV-uninfected women, aged 40 or more years old had a higher HPV 16 seroprevalence compared to women aged less than 40 years old.
CONCLUSIONS: We did not observe a strong association between age and positive HPV antibodies nor an association between pregnancy and HPV seroprevalence. HPV seroprevalence was significantly higher among HIV-infected women compared to HIV negative women. In both populations the seroprevalence to all four HPV vaccine types was low suggesting that women may potentially benefit from the HPV vaccines.