ABSTRACT
In Brazil, epizootics among New World monkey species may indicate circulation of yellow fever (YF) virus and provide early warning of risk to humans. Between 1999 and 2001, the southern Brazilian state of Rio Grande do Sul initiated surveillance for epizootics of YF in non-human primates to inform vaccination of human populations. Following a YF outbreak, we analyzed epizootic surveillance data and assessed YF vaccine coverage, timeliness of implementation of vaccination in unvaccinated human populations. From October 2008 through June 2009, circulation of YF virus was confirmed in 67 municipalities in Rio Grande do Sul State; vaccination was recommended in 23 (34%) prior to the outbreak and in 16 (24%) within two weeks of first epizootic report. In 28 (42%) municipalities, vaccination began more than two weeks after first epizootic report. Eleven (52%) of 21 laboratory-confirmed human YF cases occurred in two municipalities with delayed vaccination. By 2010, municipalities with confirmed YF epizootics reported higher vaccine coverage than other municipalities that began vaccination. In unvaccinated human populations timely response to epizootic events is critical to prevent human yellow fever cases.
Subject(s)
Primate Diseases/epidemiology , Yellow Fever Vaccine/administration & dosage , Yellow Fever/epidemiology , Yellow Fever/veterinary , Yellow fever virus/isolation & purification , Animals , Brazil/epidemiology , Epidemiological Monitoring , Haplorhini , Humans , Primate Diseases/virology , Vaccination/methods , Yellow Fever/prevention & control , Yellow Fever/virologyABSTRACT
OBJECTIVE: To evaluate the incidence of Hib meningitis before and after the implementation of a vaccination program in the state of Rio Grande do Sul State, southern Brazil, in 1999. METHODS: This retrospective study summarizes all data concerning Hib meningitis recorded by the state of Rio Grande do Sul Department of Health/Acute Communicable Disease Surveillance Agency between 1995 and 2001. All data were analyzed using the chi-square test (statistical significance: p < 0.005). RESULTS: The decline in the number of cases of Hib meningitis was associated with the Hib vaccine coverage in children. From 1995 to 2001 the incidence of Hib meningitis decreased 89% (from 1.35 cases/100,000 people in 1995 to 0.15 cases/100,000 in 2001 (p < 0.01), especially in children younger than 1 year (p < 0.005). In the same period, Hib meningitis lethality decreased from 17.8 to 6.7 % (p < 0.01). CONCLUSIONS: The implementation of an Hib meningitis vaccination program has nearly eliminated Hib meningitis in the state of Rio Grande do Sul. These findings underscore the need to maintain the vaccination in children, with a thorough investigation of suspected cases and reporting of confirmed cases.
Subject(s)
Haemophilus Vaccines/administration & dosage , Haemophilus influenzae type b/immunology , Immunization Programs , Meningitis, Haemophilus/epidemiology , Adolescent , Adult , Age Distribution , Brazil/epidemiology , Child , Child, Preschool , Humans , Incidence , Infant , Meningitis, Haemophilus/prevention & control , Retrospective StudiesABSTRACT
OBJETIVO: Avaliar a incidência de meningite por Hib antes e após a introduçäo da vacinaçäo de rotina contra esse agente no Rio Grande do Sul em 1999. MÉTODOS: Este estudo retrospectivo representa todos os dados sobre meningites por Hib investigados pela Coordenaçäo do Controle de Doenças Transmissíveis Agudas (CCDTA - sistema de vigilância) da Secretaria da Saúde do Rio Grande do Sul entre 1995 e 2001. Todos os dados foram analisados usando o teste de qui-quadrado, com p < 0,05 sendo considerado estatisticamente significativo. RESULTADOS: A diminuiçäo dos casos de meningites por Hib esteve associada com a realizaçäo da vacinaçäo em larga escala contra Hib na infância. De 1995 a 2001, a incidência das meningites por Hib diminuiu 89 por cento: de 1,35 casos/100.000 habitantes em 1995 para 0,15 casos/100.000 em 2001 (p < 0,01), especialmente em crianças menores de um ano (p < 0,005). No mesmo período, a letalidade das meningites por Hib diminuiu de 17,8 por cento para 6,7 por cento (p < 0,01). CONCLUSÕES: A introduçäo do programa de vacinaçäo contra Hib resultou na quase eliminaçäo das meningites por Hib no Rio Grande do Sul. Esses achados reforçam a necessidade de manter a vacinaçäo apropriada na infância, com a investigaçäo completa e a comunicaçäo dos casos meningites por Hib
