Objectives: To retrospectively determine the prevalence of anti-hepatitis A virus (HAV) antibody in HIV-positive persons with different routes of HIV exposure and to describe its characteristics in order to guide vaccination policy.
Methods: The prevalence of anti-HAV antibody was compared between 1580 HIV-positive persons seeking medical attention and 2581 HIV-negative controls seeking health check-ups, who had undergone anti-HAV tests between 2004 and 2007. Comparisons were also made among groups of the HIV-positive patients who had acquired HIV via different routes of transmission. A multivariate logistic regression model was built to identify independent variables associated with anti-HAV seropositivity.
Results: The overall prevalence of anti-HAV antibody was 60.9% in the HIV-positive and 48.0% in the controls (p<0.001). The overall adjusted odds ratio (AOR) for positive anti-HAV antibody was 2.604 (95% confidence interval (CI) 2.106-3.219) in HIV-positive persons compared with HIV-negative persons. In addition, HIV-positive men who have sex with men (MSM), heterosexuals, and injecting drug users (IDU) all had significantly higher AOR for positive anti-HAV antibody than HIV-negative persons. In HIV-positive persons, older age (AOR 1.284, 95% CI 1.246-1.322) and IDU (AOR 5.137, 95% CI 3.499-7.542) were independently associated with an increased prevalence of anti-HAV antibody. Nearly 90% of the IDU had become seropositive for HAV after age 36-40 years, compared with heterosexuals and MSM after age 46-50 years, and controls after age 51-55 years.
Conclusion: Our findings suggest that age groups to be targeted for HAV vaccination vary with the different routes of HIV exposure.