BCG Tuberculosis Vaccine: Immunological and Clinical Efficacy in Children Born to HIV-Infected Women

Abstract

The article analyses the efficacy of vaccination and its influence on the nature of tuberculosis process in children perinatally exposed to HIV. The study analysed hospital records, hospital discharge summaries and outpatient medical records of children under 14 with tuberculosis: there were 109 HIV-infected children and 97 children perinatally exposed to HIV (but not HIV-infected). The postvaccinal immunity status was assessed by the presence and size of the vaccination scar and the response to the Mantoux test. The clinical efficacy of the BCG vaccination was assessed by the severity of tuberculosis in vaccinated and non-vaccinated children. It was shown that immunization with BCG vaccine (BCG-M) was safe and efficacious in children born to HIV-infected women but not infected with HIV. At the same time the vaccine did not demonstrate sufficient immunological and clinical efficacy in HIV-infected children: the response to the Mantoux test, 2 TU, was positive only in one third of all vaccinated children; there was no statistically significant difference in the frequency of disseminated processes in vaccinated children as compared to the non-vaccinated children perinatally exposed to HIV. A conclusion was made that children born to HIV-infected mothers but not infected with HIV must be vaccinated during the neonatal period. The vaccination of HIV- infected children is not advisable due to its low clinical efficacy and the risk of development of disseminated complications, for instance, the generalized BCG infection in HIV-infected children may develop over a period of 3 years after vaccination.

Keywords

• tuberculosis
• bcg vaccine
• vaccine efficacy and safety
• hiv infection
• hiv-exposed children
• mantoux test