RESUMEN
A steady increase in the incidence of Guillain-Barré syndrome (GBS) with a seasonal preponderance, almost exclusively related to Campylobacter jejuni, and a rise in the incidence of laboratory-confirmed Campylobacter enteritis have been reported from Curaçao, Netherlands Antilles. We therefore investigated possible risk factors associated with diarrhea due to epidemic C. jejuni. Typing by pulsed-field gel electrophoresis identified four epidemic clones which accounted for almost 60% of the infections. One hundred six cases were included in a case-control study. Infections with epidemic clones were more frequently observed in specific districts in Willemstad, the capital of Curaçao. One of these clones caused infections during the rainy season only and was associated with the presence of a deep well around the house. Two out of three GBS-related C. jejuni isolates belonged to an epidemic clone. The observations presented point toward water as a possible source of Campylobacter infections.
Asunto(s)
Infecciones por Campylobacter/epidemiología , Campylobacter jejuni , Adulto , Campylobacter jejuni/clasificación , Campylobacter jejuni/genética , Campylobacter jejuni/aislamiento & purificación , Estudios de Casos y Controles , Escolaridad , Electroforesis en Gel de Campo Pulsado , Familia , Femenino , Humanos , Renta , Masculino , Antillas Holandesas/epidemiología , Valores de Referencia , Factores de Riesgo , Serotipificación/métodosRESUMEN
Campylobacter jejuni is a major cause of pediatric diarrhea in developing countries-free-ranging chickens are presumed to be a common source. Campylobacter strains from monthly surveillance and diarrhea cases were compared by means of restriction-fragment length polymorphism (RFLP), rapid amplified polymorphic DNA, and Lior serotyping. RFLP analysis of 156 human and 682 avian strains demonstrated identical strains in chickens and humans in 29 (70.7%) of 41 families, and 35%-39% of human isolates from diarrhea and nondiarrhea cases were identical to a household chicken isolate. Isolation of the same RFLP type from a household chicken and a human within 1 month was highly protective against diarrhea (odds ratio, 0.07; P<.005). Campylobacter strains from symptomatic humans were unlikely to be identical to strains recently carried by household chickens, limiting the potential benefits from household-based control measures.
Asunto(s)
Infecciones por Campylobacter/microbiología , Infecciones por Campylobacter/transmisión , Campylobacter/clasificación , Campylobacter/aislamiento & purificación , Pollos/microbiología , Zoonosis/microbiología , Zoonosis/transmisión , Adolescente , Adulto , Animales , Campylobacter/genética , Infecciones por Campylobacter/epidemiología , Infecciones por Campylobacter/veterinaria , Niño , Vivienda para Animales , Humanos , Estudios Longitudinales , Perú/epidemiología , Polimorfismo de Longitud del Fragmento de Restricción , Enfermedades de las Aves de Corral/epidemiología , Enfermedades de las Aves de Corral/microbiología , Enfermedades de las Aves de Corral/transmisión , Técnica del ADN Polimorfo Amplificado Aleatorio , Factores de Riesgo , Serotipificación , Zoonosis/epidemiologíaRESUMEN
Between 9 October and 12 November 1996, an outbreak of bloody diarrhea occurred in the neonatal nursery ward of the Policlínico Neuquén, in Neuquén, a city in the southwestern region of Argentina. Seven patients of the intermediate care unit were affected. Isolates of Escherichia coli O18ac:H31 that were non-lactose and -sorbitol fermenting were recovered from outbreak cases. Although the strains were negative for a number of virulence factors typically found in diarrheagenic groups of E. coli, all isolates from the present neonatal outbreak possessed the enterohemolysin gene, ehl1. All isolates showed resistance to the antibiotics ampicillin and chloramphenicol. These isolates showed a low adherence property in HeLa cells without any recognizable pattern. In order to evaluate the outbreak dissemination in the neonatology ward, a prevalence study was conducted on 13 November. Stool specimens were obtained from 16 neonates hospitalized in the sector and from 33 medical staff members. E. coli isolates with identical biochemical characteristics of the outbreak strain were recovered from 11 of 16 inpatients and from 4 of 33 staff members during the prevalence study. A total of 15 E. coli strains recovered both from the outbreak and the prevalence study were processed by random amplified polymorphic DNA (RAPD)-PCR and pulsed-field gel electrophoresis (PFGE). By RAPD-PCR 14 of 15 strains showed patterns with 85 to 100% similarity, and by PFGE these strains were identical, each showing a unique pattern with 15 bands between 40 and 400 kb. One strain isolated from a nurse during the prevalence study presented a pattern not related to the others, and this was characterized as E. coli O81:HNM resistant to ampicillin only and negative for all the virulence factors studied. This outbreak occurred despite strict regulations in place to prevent cross-infection in the hospital. Postoutbreak prevalence studies were performed weekly thereafter without detecting new cases.