Impacto da vacinação contra o Haemophilus influenzae b na redução de meningites, Goiás

Resumo

Objective To assess the impact of the Haemophilus influenzae b (Hib) conjugate vaccine in reducing the incidence of meningitis among children under five years old.Methods A ‘before-after’ design was used to compare Hib meningitis incidence rates in the pre-vaccine (July 1995 - June 1999) and post-vaccine (July 1999 - June 2001) periods in the state of Goiás, central Brazil. Bacterial meningitis case definition was based on World Health Organization criteria. Incidence rates of S. pneumoniae and N. meningitidis were used for comparison purposes. Chi-squared and Student’s t tests were used for statistical analysis. P-values below 0.05 were considered as statistically significant. Results 979 children with acute bacterial meningitis were detected throughout the entire period. The incidence rate of Hib meningitis decreased from 10.8 (x105) in the pre-vaccine period to 2.3 (x105) in the 2nd year post vaccination, leading to a risk reduction of 78%, targeted to the 7-23 months age group (p<0.05). A total of 65 cases of Hib meningitis were prevented. An increase in S. pneumoniae meningitis was observed. Vaccine failure was detected in one child. Conclusions This study showed that mass immunization with Hib conjugate vaccine brought about an expressive decline in childhood Hib meningitis in Goiás soon after the first year. Notwithstanding, an enhancement of surveillance using high-accuracy tools is essential to: (i) detect a possible reemergence of Hib; (ii) identify vaccine failure, and (iii) monitor changes in the H. influenzae serotype profile over time.

Descrição

Palavras-chave

Efetividade, Effectiveness, Haemophilus influenzae tipo b, Meningite por Haemophilus, Prevenção, Vacinas anti-Haemophilus, Haemophilus influenzae type b, Meningitis, Haemophilus, Prevention control, Haemophilus Vaccines

Citação

SIMÕES, Luciana Leite Pineli et al. Impacto da vacinação contra o Haemophilus influenzae b na redução de meningites, Goiás. Revista de Saúde Pública, São Paulo, v. 38, n. 5, p. 664-670, 2004.