Socio-demographic and behavioral determinants of hepatitis B vaccination and infection in pregnant women on Mayotte Island, Indian Ocean.

BACKGROUND: Socio-demographic and behavioral determinants of Hepatitis B virus (HBV) vaccination and infection among pregnant women (PW) of Mayotte Island (Indian Ocean) are not well understood. METHODS: Six hundred and seventy-one pregnant women presenting to public antenatal clinics on Mayotte Island were included between September 15, 2008 and September 27, 2009. Socio-demographics, sexual risk behavior characteristics, and data for HBV biomarkers were collected. Logistic regression was undertaken to study determinants of HBV vaccination and factors associated with the risk of HBV infection were assessed using a survival method adapted to interval-censored data. Due to missing data for HBV biomarkers, data were analyzed using multiple imputation (MI). RESULTS: Past or recent HBV infection was observed for 35.5% (95% confidence interval (CI): 30.4-40.8) of PW and 18.6% (95% CI: 14.7-23.2) had evidence of HBV vaccination. PW with unemployed and education qualification (adjusted odds ratio (aOR) 2.65, 95% CI 1.52-4.60) and student status (aOR 4.79, 95% CI 1.63-4.07) were better vaccinated against HBV, compared to those without employment and education. Being born on Comoros was associated with a 63% reduction in HBV vaccination (aOR 0.37, 95% CI 0.21-0.65), compared to be born in Mayotte/France. Women with a history of sexually-transmitted infections in the last 5 years had an increased risk of HBV infection (adjusted hazard ratio (aHR) 3.10, 95% CI: 1.13-8.50), whereas those who sometimes used condoms had a 60% reduced risk (aHR=0.40, 95% CI: 0.23-0.69). CONCLUSIONS: Socio-demographic factors were identified for HBV vaccination, while behavioral factors were observed for HBV infection. These results could help to determine priorities for intervention.

Prevalence and risk factors for HIV, hepatitis B virus, and syphilis among pregnant women in Mayotte, Indian Ocean, 2008-2009.

OBJECTIVE: To assess the prevalence and risk factors for HIV, hepatitis B virus (HBV), and syphilis among pregnant women living on the Indian Ocean island of Mayotte. METHODS: A cross-sectional survey was conducted among 671 pregnant women at 11 prenatal clinics on Mayotte between September 15, 2008, and September 27, 2009. Sociodemographic and behavioral characteristics were collected by interviewer-administered questionnaire. Blood samples were obtained for HIV, HBV, and syphilis testing. Risk factors were analyzed by exact logistic regression. RESULTS: No prevalent case of HIV infection was detected among the study population. The prevalence of HBV surface antigen and active syphilis (defined as a positive test result by both rapid plasma reagin and Treponema pallidum hemagglutination assays) was 3.4% and 2.1%, respectively. A positive HBV surface antigen test was associated with being born in Comoros and having sex with a casual partner during the previous year. Lack of education and a history of sexually transmitted infections in the past 5 years were associated with active syphilis. CONCLUSION: The continuing low prevalence of HIV and high prevalence of sexually transmitted infections among pregnant women on Mayotte confirmed the so-called "Indian Ocean paradox."