Impact of introduction of the Haemophilus influenzae type b conjugate vaccine into childhood immunization on meningitis in Bangladeshi infants.

OBJECTIVES

Some Asian countries have been reluctant to adopt Haemophilus influenzae type b (Hib) conjugate vaccination because of uncertainty over disease burden. We assessed the impact of introduction of Hib conjugate vaccine into the Expanded Program on Immunization in Bangladesh on purulent and laboratory-confirmed H influenzae meningitis.

STUDY DESIGN

Within a well-defined catchment area around 2 surveillance hospitals in Dhaka, Bangladesh, we compared the incidence of Hib meningitis confirmed by culture, latex agglutination, and polymerase chain reaction assay among infants 1 year before and 1 year after introduction of Hib conjugate vaccine. We adjusted the incidence rate for the proportion of children who sought care at the surveillance hospitals.

RESULTS

Among infants, the incidence of confirmed Hib meningitis decreased from 92-16 cases per 100,000 within 1 year of vaccine introduction (vaccine preventable incidence = 76; 95% CI 18, 135 per 100,000). The incidence of purulent meningitis decreased from 1659-1159 per 100,000 (vaccine preventable incidence = 500; 95% CI: 203, 799 per 100,000). During the same time period, there was no significant difference in the incidence of meningitis due to Streptococcus pneumoniae.

CONCLUSIONS

Introduction of conjugate Hib conjugate vaccine into Bangladesh Expanded Program on Immunization markedly reduced the burden of Hib and purulent meningitis.