Long-term Immunogenicity of Single Dose of Live Attenuated Hepatitis A Vaccine in Indian Children.

Objectives: To assess immunogenicity of a single dose of live attenuated hepatitis A vaccine in Indian children, ten years after immunization. Methods: Of 143 children vaccinated in 2004, 121 children were evaluated in 2014, clinically and for anti-HAV antibodies. Results: 13 children were early vaccine failures who received two doses of HAV vaccine subsequently. 106 (98%) of 108 remaining children had seroprotective levels with a geometric mean titer of 100.5 mIU/mL. On analysis of all 121 children, the immunogenicity was 87.6%. Conclusion: Single dose of live attenuated hepatitis A vaccine provides long-term immunity in Indian children.