Immunogenicity study of Haemophilus influenzae type B conjugate vaccine in Indian infants
Phadke, M.A.; Kulkarni, M.V.; Sovani, V.B.; Lokeshwar, M.R.; Venkataraman, R.
Indian Pediatrics 34(9): 779-783
1997
ISSN/ISBN: 0019-6061 PMID: 9492415 Document Number: 474757
To assess the immunogenicity in Indian infants to Haemophilus influenzae b oligosaccharide conjugate vaccine (HbOC). Prospective multicenter study. Pediatric Out Patient Department of general hospitals in Pune and Mumbai. 124 full term healthy infants brought for routine DPT/OPV immunization. Infants were administered 3 doses of 0.5 ml of HbOC, on the same day as their DPT/OPV immunization, injected intramuscularly on the limb opposite to that where DPT vaccine was administered. Data on local reactions and general symptoms was collected for three days after every dose. The children had their blood collected for assay of anti PRP (polyribosil ribitol phosphate) antibody titers, along with the first injection and one month after the third injection. One hundred and three infants completed the study protocol with two blood collections. The initial geometric mean titers (GMT) of 0.124 mcg/ml rose by 37 times to 4.552 mcg/ml. Ninety eight children (95.1%) had a final titer of > or = 0.15 mcg/ml, the minimum level associated with protection, and 77 children (74.8%) had a final level of > or = 1.0 mcg/ml, a level associated with long term protection. HbOC is immunogenic in Indian infants when used as per the locally recommended DPT/OPV immunization schedule.