Controlled trial of Giardia lamblia: control strategies in day care centers

The protozoan organism Giardia lamblia causes fever, diarrhea, cramps, weakness, and other symptoms, and is becoming increasingly common in day care centers, especially those that care for infants and toddlers. Whether infected children with no symptoms (asymptomatic) pass on the infection is not documented. Three different control strategies of controlling the spread of infection were tried at various day care centers. One group of day care centers treated symptomatic and asymptomatic children, and readmitted them after two negative stool tests, according to the existing policy. The second and third groups of centers treated symptomatic infections only, but the third group also treated asymptomatic children at the center. At the two groups of centers where both symptomatic and asymptomatic children were treated, there were significant reductions in Giardia prevalence, and a smaller reduction was found in the group of centers where only symptomatic children were treated. Part of the immediate reduction in prevalence occurred because asymptomatic children moved to other day care centers. At six months, none of the prevention strategies produced significantly fewer infections, but all three groups had lower prevalences than at the beginning of the study. Although it is not possible to draw general conclusions based on this study, the findings suggest that testing of all toddlers should be considered if there is an outbreak of diarrhea at a day care center. (Consumer Summary produced by Reliance Medical Information, Inc.)