HBV Vaccination: Birth Dose Safe, May Reduce HIV Coinfection

Two new studies provide further evidence supporting hepatitis B vaccination. A systematic review published online Feb. 5 in Pediatrics confirms that administering the hepatitis B vaccine at birth is safe and effective, while a cohort study in Open Forum Infectious Diseases finds that childhood vaccination may significantly reduce hepatitis B virus (HBV) coinfection in people with HIV.

Researchers from the University of Minnesota conducted a comprehensive review of the evidence on the safety, immunogenicity, efficacy, and effectiveness of the birth dose of hepatitis B vaccination compared with a delayed first dose. They found strong evidence for the safety and effectiveness of the birth dose, and no evidence that a delayed first dose improves safety or effectiveness. No evidence was found to support the use of postvaccination serology for clinical decision-making. Infant vaccination has resulted in a 99 percent reduction in pediatric HBV infections, the authors note. "The birth dose has served to close real-world gaps in prenatal screening and follow-up that left infants vulnerable to infection, including postnatal infections, errors across the continuum of care, missed opportunities for vaccination, gaps in early pediatric care, and equitable access," they write.

In a separate study, researchers analyzed baseline data from 5,598 adults receiving HIV care in the Johns Hopkins HIV Clinical Cohort in Baltimore, Maryland, to examine HBV coinfection prevalence by birth cohort in relation to U.S. HBV vaccination policy eras. Patients were born between 1940 and 1999 and underwent hepatitis B surface antigen testing within 12 months of cohort entry. Overall HBV coinfection prevalence was 6.7%. When broken down by birth cohort, prevalence was 6.2% for those born 1940–1959, 7.9% for 1960–1979, and 2.6% for 1980–1999. After adjustment for demographic and clinical characteristics, individuals born after 1980 were significantly less likely to have HBV coinfection compared with those born earlier (adjusted prevalence ratio 0.19; 95% CI 0.09–0.42). This corresponded to approximately 6 fewer HBV infections per 100 individuals in the post-1980 cohort. The association remained significant among men who have sex with men and among those without a history of injection drug use. The researchers suggest that broader implementation of childhood HBV vaccination may explain the lower prevalence in the post-1980 birth cohort, though HBV coinfection remained more common in this younger HIV population than in the general U.S. population. Study limitations include the use of a single clinical cohort, incomplete testing, lack of vaccination history, and a small post-1980 sample. The study was supported by the National Institutes of Health.