Abstract
Background & objectives: Vaccine policy depends on locally relevant disease burden estimates. The incidence of Haemophilus influenzae type b (Hib) disease is not well characterized in the South Asian region, home to 30 per cent of the world's children. There are limited data from prospective population incidence studies of Rib in Asia, and no data available from India. We therefore carried out this study to assess the burden of Rib meningitis in India.
Methods: A prospective surveillance study was carried out during 1997 and 1999 in hospitals for cases of Rib meningitis from 5 administrative areas of an Indian district (Vellore, Tamil Nadu) with 56,153 children under 5 yr of age, over a 24 month period.
Results: Ninety seven cases of possible meningitis (> 10 WBC/mu l in CSF) were reported, an annual incidence of 86 per 100,000 (95%CI 69 to 109) in 0-4 yr old children, and 357 per 100,000 in 0-11 month infants. Eighteen had proven bacterial meningitis, an annual incidence of 15.9 per 100,000. Eight CSF had Rib by culture or antigen testing, an annual incidence of 7.1 per 100,000 (95% CI 3.1 to 14.0) in children 0-59 months. In infants 0-11 months of age, the incidence of Rib meningitis was 32 per 100,000 (95% CI 16 to 67) and in the 0-23 month group it was 19 (95% CI 8 to 37).
Interpretation & conclusions:Our data are the first minimal estimate of the incidence of Rib meningitis for Indian children. The observed incidence data are similar to European reports before Rib vaccine use, suggest substantial disease before 24 months of age, and provide data useful for policy regarding Rib immunization.