RESUMEN
In July 2011, a cluster of Yersinia enterocolitica infections was detected in southwestern Pennsylvania, USA. We investigated the outbreak's source and scope in order to prevent further transmission. Twenty-two persons were diagnosed with yersiniosis; 16 of whom reported consuming pasteurized dairy products from dairy A. Pasteurized milk and food samples were collected from this dairy. Y. enterocolitica was isolated from two products. Isolates from both food samples and available clinical isolates from nine dairy A consumers were indistinguishable by pulsed-field gel electrophoresis. Environmental and microbiological investigations were performed at dairy A and pasteurization deficiencies were noted. Because consumption of pasteurized milk is common and outbreaks have the potential to become large, public health interventions such as consumer advisories or closure of the dairy must be implemented quickly to prevent additional cases if epidemiological or laboratory evidence implicates pasteurized milk as the outbreak source.
Asunto(s)
Enfermedades Transmitidas por los Alimentos/epidemiología , Leche/microbiología , Yersiniosis/epidemiología , Yersinia enterocolitica/aislamiento & purificación , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Estudios de Cohortes , Electroforesis en Gel de Campo Pulsado , Femenino , Enfermedades Transmitidas por los Alimentos/microbiología , Genotipo , Humanos , Lactante , Masculino , Persona de Mediana Edad , Tipificación Molecular , Pennsylvania/epidemiología , Yersiniosis/microbiología , Yersinia enterocolitica/clasificación , Yersinia enterocolitica/genética , Adulto JovenRESUMEN
The Vaccine Adverse Event Reporting System (VAERS) is the passive reporting system for postmarketing surveillance of vaccine safety in the United States. The proportion of cases of an adverse event after vaccination that are reported to VAERS (i.e., VAERS reporting completeness) is mostly unknown. Therefore, the risk of such an event cannot be derived from VAERS only. To study whether its reporting sensitivity and risks could be estimated, VAERS was linked to data from a case-control and a retrospective cohort study in a capture-recapture analysis of intussusception after rotavirus vaccination (RV). Cases of intussusception after RV were selected from the common time frame (December 1998 through June 1999) and the common geographic area (19 states) of the three sources. Matching occurred on birth date, gender, state, date of vaccination, and date of diagnosis. Thirty-five matches were identified among a total of 84 cases. The estimated VAERS reporting completeness was 47%. The relative risks of intussusception in the periods 3-7 and 8-14 days after RV (relative risk = 22.7 and 4.4, respectively) were comparable with those reported in the two studies. Linkage of VAERS to complimentary data sources may permit more timely postmarketing assessment of vaccine safety.