Response to immunization with measles, tetanus, and Haemophilus influenzae type b vaccines in children who have human immunodeficiency virus type 1 infection and are treated with highly active antiretroviral therapy.

OBJECTIVE

To assess the level of immunity to measles, tetanus, and Haemophilus influenzae type b (Hib) in previously immunized children who have human immunodeficiency virus (HIV) infection and were treated with highly active antiretroviral therapy (HAART) and to determine the response to reimmunization.

METHODS

Retrospective review of clinical data from children who have HIV-1 infection and were treated with HAART. Children were included in the analysis when they had a history of immunizations before treatment with HAART; had specific immunoglobulin G levels to tetanus, measles, or Hib measured after starting HAART but before the receipt of additional immunizations; were reimmunized while on HAART; and had postimmunization immunoglobulin G levels available.

RESULTS

Nineteen children (median age: 7 years; range: 3-14 years) who were treated with 3 to 5 drug HAART regimens for a median of 20 months (range: 8-37) met the criteria for at least 1 antigen and were included in this review. Fifteen (79%) of the 19 had plasma RNA levels <50 copies/mL. The median CD4% before HAART was 26% (range: 1-41) and at the time of immunization, 35% (range: 20-54). Before reimmunization, 1 (5%) of 18 children had detectable antibody levels to measles, 6 (35%) of 17 had detectable antibody levels to tetanus, and 14 (78%) of 18 had detectable antibody levels to Hib. After immunization, 15 (83%) of 18, 10 (90%) of 11, and 3 (75%) of 4 seroconverted to measles, tetanus, and Hib, respectively. Antibody levels remained detectable after 1 year in the majority of children tested.

CONCLUSIONS

Consideration should be given to readministering childhood immunizations to children who have HIV infection and are treated successfully with combination antiretroviral therapy.