RESUMO
OBJECTIVES: To report the epidemiology of invasive Haemophilus influenzae type b (Hib) disease in high-risk Alaska Native infants before and after universal infant Hib vaccination and evaluate an increase in invasive Hib disease in 1996 after changing Hib vaccine type. STUDY DESIGN: Statewide laboratory surveillance for invasive Hib disease has been conducted since 1980. Three cross-sectional Hib carriage studies were conducted in 1997 and 1998. RESULTS: The invasive Hib disease rate in Alaska Natives decreased from 332 cases per 100,000 children <5 years old in 1980-1991 to 17:100,000 in 1992-1995 but increased primarily in rural areas to 57.9:100,000 after a switch in Hib vaccine types. Carriage studies in 5 rural Alaska Native villages showed oropharyngeal Hib carriage as high as 9.3% in children aged 1 to 5 years; in contrast, carriage in urban Alaska Native children was <1%. CONCLUSIONS: Although Hib disease has decreased in Alaska, the rate of Hib disease and carriage in rural Alaska Natives did not decrease to the same extent as in non-Natives and urban Alaska Natives. Use of polyribosylribitol phosphate-outer-membrane protein conjugate vaccine for the first vaccine dose is critical to disease control in this population with continued transmission in infants <6 months of age. The ability to eliminate Hib carriage and disease may be affected by population characteristics, vaccination coverage, and Hib vaccine type used. This may pose a challenge to global elimination of Hib.
Assuntos
Portador Sadio , Infecções por Haemophilus/prevenção & controle , Vacinas Anti-Haemophilus , Haemophilus influenzae tipo b , Orofaringe/virologia , Vacinas Conjugadas , Adolescente , Alaska/epidemiologia , Criança , Pré-Escolar , Estudos Transversais , Infecções por Haemophilus/epidemiologia , Infecções por Haemophilus/etnologia , Humanos , Lactente , Inuíte/estatística & dados numéricos , Vigilância da População , Fatores de Risco , Saúde da População Rural , VacinaçãoRESUMO
Haemophilus influenzae es el más importante microorganismo que causa serias infecciones bacterianas en niños. Un importante factor asociado con el riesgo de enfermedad invasiva es la edad, con un pico de incidencia entre los 6 y 23 meses. Esta revisión tiene como finalidad presentar al médico pediatra una actualización sobre el amplio espectro de infecciones invasivas por haemophilus influenzae.