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

Abstract

ObjectiveTo 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 (x10 5 ) in the pre-vaccine period to 2.3 (x10 5 ) in the 2 nd 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.

Impact of the Haemophilus influenzae type b vaccination program on HIB meningitis in Brazil

“…In Brazil, no studies have been published with large time series to evaluate the incidence and mortality rates in the pre-vaccination period. However, the present study's findings on the trend in incidence rates are similar to those reported by Simões et al 22 .…”

“…The sharp decrease in these rates for HIB meningitis corroborates the conjugate vaccine's effectiveness in Brazil. However, the expansion of vaccine coverage and monitoring of HIB invasive diseases should be encouraged in the country in order to prevent cases and deaths and to evaluate the need for a booster dose 22 . The declining rates for unspecified bacterial meningitis appear to result from improved diagnostic quality, and it is reasonable to suppose that a residual number of HIB meningitis cases in that group may also have been prevented by the specific vaccination.…”

Características epidemiológicas da Meningite na 7ª Regional de Saúde do Estado do Paraná, no período de 2010-2019

“…Foi no ano de 2010 que o calendário nacional de imunização da criança sofreu alterações, tendo inclusão da vacina conjugada meningocócica C e pneumocócica 10-valente (Gonçalves et al, 2014). Desse modo, com a inclusão das vacinas era esperado que após o ano de 2010 os casos se encontrassem em incidência menor, seguindo exemplo já visto de reduções de casos de meningite após a inclusão da vacina contra Haemophilus influenzae b em meados de 1999 (Simões et al, 2004).…”

Uma abordagem baseaeda em Redes Neurais Artificiais para o auxílio ao diagnóstico de doenças meningocócicas

“…O número de casos registrados da meningite acarretada pela bactéria Haemophilus influenzae foi considerado insuficiente para o consequente treinamento, sendo desconsiderada a sua classificação. O baixo número de acometimentos por este agente infeccioso detectado nesta base de dados torna evidente as ações nacionais de vacinação implementadas em prol de sua erradicação [9].…”