Outbreak of salmonellosis linked to live poultry from a mail-order hatchery.

BACKGROUND: Outbreaks of human salmonella infections are increasingly associated with contact with live poultry, but effective control measures are elusive. In 2005, a cluster of human salmonella Montevideo infections with a rare pattern on pulsed-field gel electrophoresis (the outbreak strain) was identified by PulseNet, a national subtyping network. METHODS: In cooperation with public health and animal health agencies, we conducted multistate investigations involving patient interviews, trace-back investigations, and environmental testing at a mail-order hatchery linked to the outbreak in order to identify the source of infections and prevent additional illnesses. A case was defined as an infection with the outbreak strain between 2004 and 2011. RESULTS: From 2004 through 2011, we identified 316 cases in 43 states. The median age of the patient was 4 years. Interviews were completed with 156 patients (or their caretakers) (49%), and 36 of these patients (23%) were hospitalized. Among the 145 patients for whom information was available, 80 (55%) had bloody diarrhea. Information on contact with live young poultry was available for 159 patients, and 122 of these patients (77%) reported having such contact. A mail-order hatchery in the western United States was identified in 81% of the trace-back investigations, and the outbreak strain was isolated from samples collected at the hatchery. After interventions at the hatchery, the number of human infections declined, but transmission continued. CONCLUSIONS: We identified a prolonged multistate outbreak of salmonellosis, predominantly affecting young children and associated with contact with live young poultry from a mail-order hatchery. Interventions performed at the hatchery reduced, but did not eliminate, associated human infections, demonstrating the difficulty of eliminating salmonella transmission from live poultry.

Outbreak of shiga toxin-producing Escherichia coli serotype O26: H11 infection at a child care center in Colorado.

BACKGROUND: Shiga toxin-producing Escherichia coli (STEC) O26:H11 is an emerging cause of disease with serious potential consequences in children. The epidemiology and clinical spectrum of O26:H11 are incompletely understood. We investigated an outbreak of O26:H11 infection among children younger than 48 months of age and employees at a child care center. METHODS: Every employee at the center (n = 20) and every child <48 months (n = 55) were tested for STEC and administered a questionnaire. Thirty environmental health inspections and site visits were conducted. A cohorting strategy for disease control was implemented. RESULTS: Eighteen confirmed and 27 suspect cases were detected. There were no hospitalizations. The illness rate was 60% for children and employees. The risk of being a case in children <36 months was twice the risk among children of 36 to 47 months (risk ratio: 2.10; 95% confidence interval: 1.00, 4.42). The median duration of shedding among symptomatic confirmed cases was 30.5 days (range: 14-52 days). Four (22%) confirmed cases were asymptomatic and 3 (17%) shed intermittently. Nearly half (49%) of the household contacts of confirmed cases developed a diarrheal illness. The outbreak was propagated by person-to-person transmission; cohorting was an effective disease control strategy. CONCLUSIONS: This was the largest reported outbreak of O26:H11 infection in the United States and the largest reported non-O157 STEC outbreak in a US child care center. Non-O157 STEC infection is a differential diagnosis for outbreaks of diarrhea in child care settings. Aggressive disease control measures were effective but should be evaluated for outbreaks in other settings.