Intestinal Colonization by Campylobacter jejuni , Clostridium difficile , and Clostridium perfringens among Commensal Rattus norvegicus in the Urban Areas of Tehran, Iran.

BACKGROUND: Rattus norvegicus ( R. norvegicus ) population plays a significant role in the spread of numerous diseases in urban environments. The present study is aimed at investigating the presence of Campylobacter jejuni ( C. jejuni ), C. coli , Clostridium difficile ( C. difficile ), C. difficile toxigenic, and C. perfringens in R. norvegicus captured from urban areas of Tehran, Iran.

METHODS: From October 2021 to October 2022, 100 urban rats were trapped in 5 different districts of Tehran, Iran. The genomic DNA was extracted from fecal samples, and the presence of C. jejuni , C. coli , C. perfringens , and C. difficile species was evaluated using PCR assay. Moreover, PCR was used to assess the toxicity of C. difficile isolates.

RESULTS: Overall, 30% ( n = 30/100) of fecal samples were positive for zoonotic pathogens. Based on the PCR on hippuricase ( hipO ), glycine ( gly ), CIDIF , and phospholipase C ( plc ) genes, C. perfringens and C. difficile were isolated from 18.2% ( n = 14/77) and 5.2% ( n = 4/77) of male rats. The highest frequency of C. perfringens and C . jejuni was 25% ( n = 5/20) related to the south of Tehran. Toxigenic C. difficile was not detected in all regions.

CONCLUSION: According to the findings, rats are the main reservoirs for diseases. Therefore, rodent control coupled with the implementation of surveillance systems should be prioritized for urban health.