A Sustained Epidemic of Shigellosis in Isfahan Province, 2015

Document Type: Original Article


1 Associate Professor, Epidemiology & Biostatistics Dept., School of Public Health, Isfahan University of Medical Sciences, Isfahan, Iran

2 Environment Research Committee, and Student Research Committee, Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran

3 Professor, Environmental Health Engineering Department & Environment Research Center, School of Health & Passive Defense Centre Isfahan University of Medical Sciences, Isfahan, Iran


Introduction: Shigellosis is a contagious disease with acute symptoms. Delay in detecting the disease transmission way would lead to rapid spread among the community, like what happened in Isfahan Provincein April 2015. The study aimed at evaluating the Shigella bacteria transmission medium in the outbreak that occurred in Isfahan Province, Iran.
Methods: Due to evidences reported by the university health deputy, the beginning of the Isfahan shigellosis outbreak was on April 17th, and the first records of all 8600 cases were reported on April 18th. Through the interviews with Shahreza's hospitalized cases, a wedding ceremony held on April 16th with 67 guests, most of whom were affected by diarrhea. Therefore, a cross-sectional study was designed to report, overall, the Epidemic of Shigellosis and a historical cohort in order to investigate the causes of the diarrhea based on wedding ceremony data. The guest list and their phone numbers were collected from the ceremony host. Data were collected through a phone call interview.
Data analyses were done by STATA13. The relative risk was calculated with 95% confidence interval using logistic regression.
Results:The response rate of the guests following up was 72% (48 of 67 guests), with 33 individuals suffering from diarrhea and 30 having eaten vegetables. Patients were from both sexes and all age groups. The relative risk of diarrhea for vegetable consumers was 4.1 (95% CI: 1.5 – 11.3, p=0.006).
Conclusion: Findings have provided strong evidences against Shigella contaminated vegetables as a risk factor and transmission agent for individuals who got diarrhea in Shigellosis outbreak of Isfahan Province in April 2015.


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