Screening Policies for Daycare Attendees: Lessons Learned from an Outbreak of E.coli O157:H7 in a Daycare in Waterloo, Ontario

• Published in: Canadian journal of public health 2008-07, Vol.99 (4), p.281-285
• Main Authors: Gilbert, Mark, Monk, Curt, Wang, Hsiu-Li, Diplock, Ken, Landry, Lisa
• Format: Article
• Language: English
• Subjects: Bacteria; Biological and medical sciences; Child care; Childcare workers; Culture; Diarrhea; Disease outbreaks; Disease transmission; E coli; Education; Environmental policy; Escherichia coli; Food contamination & poisoning; General aspects; Illnesses; Infections; Medical sciences; Medical screening; Medicine; Medicine & Public Health; Miscellaneous; Preschool children; Prevention and actions; Public Health; Public health. Hygiene; Public health. Hygiene-occupational medicine; RESEARCH/RECHERCHE
• ISSN: 0008-4263; 1920-7476
• DOI: 10.1007/BF03403755

Objectives: Control measures for enteric outbreaks in child care settings frequently include screening by stool cultures from symptomatic children only. We present evidence from an investigation of Escherichia coli (E. coli) O157:H7 in a daycare in Waterloo, Ontario to support implementation of a mandatory screening policy for all children during an outbreak. Methods: In addition to routine outbreak control measures employed by the health unit, stool samples from all children and staff were collected, with positive E. coli cultures typed by pulsed field gel electrophoresis (PFGE). We conducted a cohort study, using data from the environmental investigation and questionnaires administered to parents and staff, to look for risk factors for infection and to survey parent/staff knowledge regarding appropriate management of diarrhea. Results: Overall 11 E. coli O157:H7 cases were identified (7 lab-confirmed); 9 were children. No common source of infection was identified. Factors identified as possibly contributing to person-to-person transmission within the daycare included: i) the underreporting and possible attendance of symptomatic children despite alerting parents to the outbreak and requirements to keep symptomatic children at home, ii) possible transmission from an asymptomatic infected child, and iii) inconsistent understanding among parents and staff regarding diarrhea and appropriate management of a child with diarrhea. Discussion/Conclusion: This investigation reveals that in child care settings, E. coli O157:H7 outbreak screening policies based on reported symptoms only may be insufficient. We recommend that such policies be amended to include the collection of at least one stool culture from all children in attendance, regardless of symptom history. Objectifs : Les mesures de contrôle des éclosions d'infections entériques dans les milieux de garde d'enfants comprennent souvent le prélèvement de cultures de selles auprès des enfants symptomatiques seulement. Nous présentons les résultats d'une enquête sur le colibacille (Escherichia coli) O157:H7 menée dans une garderie de Waterloo, en Ontario, à l'appui de la mise en oeuvre d'une politique de dépistage obligatoire de tous les enfants lors d'une eclosión. Méthode : En plus des mesures habituelles de contrôle des éclosions préconisées par le bureau de santé, nous avons prélevé des échantillons de selles de tous les enfants et du personnel; les cultures positives pour le colibacille ont ensuite été typ