Objective: This study assessed the impact of non-routine vaccination against invasive Haemophilus influenzae (Hib)disease before the introduction of universal childhood Hib vaccination.
Methods: Data were obtained from a prospective surveillance program for invasive bacterial diseases in children <15 years of age that was begun in the Autonomous Region of Valencia on 1 December 1995.
Results: An incidence of 15.5 cases of invasive Hib disease per 100,000 children <5 years of age was reported in the first year of the surveillance program (from 1 December 1995 to 30 November 1996), when Hib vaccination coverage was estimated to be 32.5%. An increase in vaccination coverage to 44% in the second year (1 December 1996 to 30 November 1997) was associated with a reduction in disease incidence to 3.3 cases per 100,000. After the initiation of universal vaccination in December 1998, only two cases were reported. The effectiveness of non-routine vaccination was 71% in 1997.
Conclusions: These results show that before the introduction of routine childhood Hib vaccination, widespread use of the vaccine can dramatically reduce the occurrence of invasive Hib disease.
Copyright 2001 The British Infection Society.