Safety and reactogenicity of a low dose diphtheria tetanus acellular pertussis vaccine (Boostrix) in pre-school Indian children.

OBJECTIVE To evaluate the safety and reactogenicity of a reduced-antigen-content combined Diphtheria Tetanus Acellular Pertussis (dTpa) vaccine in Indian preschool children. METHODS GlaxoSmithKline Biologicals combination dTpa vaccine was administered as a single booster dose to 347 children aged 46 years in seven centers across India. All children were subsequently followed up for two weeks for safety and reactogenicity assessment. RESULTS A total of 345 subjects completed the study and two subjects were lost to follow-up. One serious adverse event (head injury) unrelated to vaccination was reported. Otherwise, all subjects were in good health throughout the study period. Three subjects (0.9%) reported transient general symptoms (such as irritability and drowsiness), which prevented normal activity. Pain at injection site, swelling and redness was reported in 31.1%, 18.2% and 8.9% subjects respectively. Five subjects (1.4%) reported severe pain preventing normal movement. This resolved within 48 hours in all cases. There were no other severe local reactions including large injection site reactions. CONCLUSION The reduced antigen content combined dTpa vaccine is safe and well tolerated in Indian pre-school children.