A Case-Control Study of Timely Control and Investigation of an Entamoeba Histolytica Outbreak by Primary Health Care in Idahluy-e Bozorg Village, Iran

Experience transfer and the knowledge utilization of rapid and timely outbreakcontrol can be the key path-finding to health systems (HSs). The aim of this study was to investigate anEntamoeba histolytica diarrhea outbreak through timely control.

A case-control study and an environmental survey were conducted to identify the sourceof infection and the outbreak etiological agent. Sixty-two confirmed cases in Idahluye Bozorg village,Iran, and 62 group-matched controls (in terms of age and sex) were selected from the healthy neighborsof the same village during the same period. Then, multiple logistic regression was applied to calculatethe adjusted odds ratio for diarrhea risk.

Totally, 250 cases were identified by a continuous common source epidemic from January19th to 31st, 2018. Out of the total 36 stool samples, E. histolytica was detected as the commonorganism. In addition, the final analysis indicated that network drinking water (NDW) increased theodds of diarrhea (16.56, 95% CI = 4.14-64.87), whereas well water and boiling water had protectiveeffects and decreased the odds of diarrhea by 81% and 66%, respectively.

Overall, the source of infection was detected due to the contamination of undergroundNDW by pipe sewage erosion. Therefore, additional monitoring of water systems is necessary,especially during the summer and regarding full readiness for outbreak control.