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

Document Type: Original Article

Authors

1 Ph.D. Candidate in Epidemiology, Department of Epidemiology and Biostatistics, School of Health, Tehran University of Medical Sciences, Tehran, Iran/Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran

2 Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran

3 MD, Research Center of Psychiatry and Behavioral Sciences, Tabriz University of Medical Sciences, Tabriz, Iran

4 Department of Disease Control and Prevention, Tabriz University of Medical Sciences, Malekan, Iran

5 Department of Communicable Disease, Tabriz University of Medical Sciences, Tabriz, Iran

Abstract

Background and aims: Experience transfer and the knowledge utilization of rapid and timely outbreak
control can be the key path-finding to health systems (HSs). The aim of this study was to investigate an
Entamoeba histolytica diarrhea outbreak through timely control.
Methods: A case-control study and an environmental survey were conducted to identify the source
of 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 neighbors
of the same village during the same period. Then, multiple logistic regression was applied to calculate
the adjusted odds ratio for diarrhea risk.
Results: Totally, 250 cases were identified by a continuous common source epidemic from January
19th to 31st, 2018. Out of the total 36 stool samples, E. histolytica was detected as the common
organism. In addition, the final analysis indicated that network drinking water (NDW) increased the
odds of diarrhea (16.56, 95% CI = 4.14-64.87), whereas well water and boiling water had protective
effects and decreased the odds of diarrhea by 81% and 66%, respectively.
Conclusion: Overall, the source of infection was detected due to the contamination of underground
NDW by pipe sewage erosion. Therefore, additional monitoring of water systems is necessary,
especially during the summer and regarding full readiness for outbreak control.

Keywords