ABSTRACT
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.
Subject(s)
Child Day Care Centers , Disease Outbreaks , Escherichia coli Infections/epidemiology , Shiga-Toxigenic Escherichia coli/isolation & purification , Adult , Child , Child, Preschool , Cohort Studies , Colorado/epidemiology , Escherichia coli Infections/microbiology , Female , Humans , Infant , Male , Middle Aged , Surveys and QuestionnairesABSTRACT
The 1st Aedes albopictus specimen recorded from Colorado was found near a tire storage site in Ft. Lupton on July 9, 2003. Intensified surveillance at the site in 2003 did not result in collection of any other specimens that season, leading to speculation that it was an isolated incident rather than an actual introduction for the species. Control measures against larvae and adult mosquitoes were conducted in the area to further reduce the likelihood of establishment of a viable population. However, subsequent surveillance during the 2004 mosquito season resulted in collection of 21 additional specimens at and near the Ft. Lupton site, possibly representing an established viable population of the species.