Immunogenicity and immunologic memory after hepatitis B virus booster vaccination in HIV-infected children receiving highly active antiretroviral therapy

Abstract

Background. Hepatitis B virus (HBV) is an important cause of comorbidity in human immunodeficiency virus (HlV)-infected individuals. The immunogenicity of HBV vaccination in children receiving highly active antiretroviral therapy (HAART) was investigated. Methods. HIV-infected children receiving HAART who had low to moderate HIV loads and who had previously received 5≥3 doses of HBV vaccine were given an HBV vaccine booster. Concentrations of antibody to hepatitis B surface antigen (anti-HBs) were determined before vaccination and at weeks 8, 48, and 96. A subset of subjects was administered a subsequent dose, and anti-HBs was measured before and 1 and 4 weeks later. Results. At entry, 24% of 204 subjects were seropositive. Vaccine response occurred in 46% on the basis of seropositivity 8 weeks after vaccination and in 37% on the basis of a ≥4-fold rise in antibody concentration. Of 69 subjects given another vaccination 4-5 years later, immunologic memory was exhibited by 45% on the basis of seropositivity 1 week after vaccination and by 29% on the basis of a ≥4-fold rise in antibody concentration at 1 week. Predictors of response and memory included higher nadir and current CD4 cell percentage, higher CD 19 cell percentage, and undetectable HIV load. Conclusions. HIV-infected children frequently lack protective levels of anti-HBs after previous HBV vaccination, and a significant proportion of them do not respond to booster vaccination or demonstrate memory despite receiving HAART, leaving this population insufficiently protected from infection with HBV © 2009 by the Infectious Diseases Society of America. All rights reserved.