Hepatitis B virus infection and vaccine-induced immunity in Madrid (Spain)

Abstract

Objective: To estimate the prevalence of hepatitis B virus (HBV) infection and vaccine-induced immunity in the region of Madrid, and to analyze their evolution over time. Methods: An observational, analytical, cross-sectional study was carried out in the population aged 16–80 years between 2008 and 2009. This was the last of four seroprevalence surveys in the region of Madrid. The prevalence of HBV infection and vaccine-induced immunity was estimated using multivariate logistic models and were compared with the prevalences in the 1989, 1993 and 1999 surveys. Results: In the population aged 16–80 years, the prevalence of HBV infection was 11.0% (95% CI: 9.8–12.3) and that of chronic infection was 0.7% (95% CI: 0.5–1.1). The prevalence of vaccine-induced immunity in the population aged 16–20 years was 73.0% (95% CI: 70.0–76.0). Compared with previous surveys, there was a decrease in the prevalence of HBV infection. Conclusions: Based on the prevalence of chronic infection (<1%), Madrid is a region with low HBV endemicity. Preventive strategies against HBV should especially target the immigrant population.

Keywords

• Hepatitis B
• Chronic hepatitis B
• Hepatitis B vaccine
• Seroepidemiologic Study
• Immunization