Safety and Immunogenicity of High-dose Edmonston-Zagreb Measles Vaccine in Children with HIV-1 Infection. A Cohort Study in Kigali, Rwanda

Objective: To compare the reactogenicity and immunogenicity of high-dose Edmonston-Zagreb (EZ) measles vaccine in children with and without human immunodeficiency virus, type 1 (HIV-1), infection.

Design: Prospective cohort study.

Setting: General pediatric clinic and home visits in Kigali, the capital of Rwanda.

Participants: Infants born to HIV-1-seropositive and -seronegative mothers were vaccinated with a 10(5.0) 50% tissue culture infective dose of EZ measles vaccine at 6 months of age. Control visits were made 10 and 14 days later to monitor local and general reactions. Measles serum antibodies were measured by an enzyme-linked immunosorbent assay technique at birth and at 6 and 9 months of age. Three groups were compared: infected children (n = 43), uninfected children born to seropositive mothers (n = 135), and uninfected children born to seronegative mothers (n = 194).

Results: Three hundred twenty-three children (86.8%) were available for the reactogenicity study. No statistically significant difference between the three groups was found in the occurrence of minor adverse reactions. No severe adverse reaction was observed. One hundred ninety children (51.1%) were available for the immunogenicity study. The percentage of infants negative for measles antibody at 6 months was significantly higher (P = .021) in HIV-infected children (85%) and in uninfected children born to seropositive mothers (90%) than in uninfected children born to seronegative mothers (75%). The overall seroconversion rate at 9 months was 90% (95% confidence interval, 85.7% to 94.3%), without any statistically significant difference between the three groups.

Conclusion: High-dose EZ vaccine administered at 6 months of age is safe and highly immunogenic in both HIV-infected and uninfected children.