American Journal of Epidemiology Vol. 138, No. 4 Copyright © 1993 by The Johns Hopkins University School of Hygiene and Public Health Printed In U.SA. All rights reserved Effect of Fecal Contamination on Diarrheal Illness Rates in Day-Care Centers Danielle J. Laborde, 1 Kristen A. Weigle, 1 David J. Weber, 1 and Jonathan B. Kotch 2 Contact spread of enteropathogens in day-care centers is supported by the recovery (presence vs. absence) of fecal conforms from hands and day-care center fomites. This prospective study was conducted to determine what, if any, quantitative measures of fecal coliforms predict the risk of diarrhea among day-care center attendees. Diarrheal illness without concomitant respiratory symptoms was monitored among 221 children aged <3 years in 37 classrooms (24 day-care centers) through biweekly parental tele- phone interviews from October 1988 to May 1989 in Cumberland County, North Carolina. The risk of diarrhea was expressed as new episodes/classroom-fortnight. Contamina- tion was expressed as the log 1o fecal coliform count per unit of surface area, per toy, and per child and staff hands. Significant predictors of diarrheal risk were any hand contamination (p = 0.003) and the number of contaminated moist sites (hands, faucets, and sinks) (p = 0.006). After adjusting for the child/staff ratio using weighted multiple regression, the authors found that classrooms with either any hand contamination (p = 0.0015) or contamination on all moist sites (p = 0.015) had a significant twofold in- creased rate of diarrhea compared with classrooms without contamination. This was the first study to demonstrate an increased risk of diarrhea associated with fecal contam- ination and the frequent sink contamination in day-care centers. Am J Epidemiol 1993;138:243-55. child; child day care centers; communicable disease control; day care; diarrhea; envi- ronmental microbiology; environmental monitoring; feces The shift in recent years from home-based child care to group day care in the United States has been paralleled by an increase in reports of infectious illness among attendees (1-8). Infectious diarrhea occurring sporad- ically (9-11) and in outbreaks (12-15) can Received for publication August 21, 1992, and in final form April 30, 1993. Abbreviations: CFU, colony-forming unit; Cl, confi- dence interval; RODAC, replicate organism detection and counting; RR, relative risk. 1 Department of Epidemiology, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC. 2 Department of Maternal and Child Health, School of Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC. Reprint requests to Dr. Danielle J. Laborde, Depart- ment of Epidemiology, School of Public Health, Univer- sity of North Carolina at Chapel Hill, CB 7400 McGravan Greenberg Hall, Chapel Hill, NC 27599. be 2-3 times more common among children attending day-care centers than among those either homebound or in day-care homes (4, 16-18). Day-care center characteristics such as young age of attendees, crowding, high asymptomatic carrier rates, and poor hy- gienic practices facilitate fecal-oral trans- mission of enteropathogens (19-21). Some studies suggest that environmental fecal contamination also has a role in transmis- sion dynamics (22-26). Recently, fecal coliforms have been used to describe the presence of fecal contami- nation in day-care center classrooms (22, 24-26). Ekanem et al. (22) found that more outbreaks occurred in contaminated class- rooms, and Van et al. (24) reported that classrooms experiencing a diarrheal episode had a higher probability of being contami- nated. Despite these advances, it is not 243