Prevalence of Clostridium difficile contamination in Iranian foods and animals: A systematic review and meta-analysis

Consumption or handling of contaminated food products has been shown as a possible source of Clostridium difficile acquisition in the community. Therefore, this study aimed to investigate the prevalence of C. difficile and toxigenic strains in Iranian food resources. A systematic search carried out to identify papers performed in Iran in the Web of Science, PubMed, Scopus, Embase, and Google Scholar electronic databases from the beginning of databases to December 2018. Then, 14 studies matched with eligibility criteria and were included for data extraction and meta-analysis. From included studies, the overall prevalence of C. difficile and toxigenic strains contamination in both foods and animals was estimated at 7.5% (95% CI: 3.7%-14.4%), and 3.5% (95% CI: 1.9%-6.4%), respectively. Of seven specific reports on raw meat samples, the pooled prevalence of C. difficile contamination and toxigenic strains were estimated at 7.7% (95% CI: 3.1%-17.9%), and 4.9% (95% CI: 2.9%-8.3%), respectively. While of three specific reports in animals the pooled prevalence of C. difficile colonization was estimated at 31.3% (95% CI: 8.8%-68.2%). Four studies showed the prevalence of toxigenic strains in animals, of which the pooled prevalence was estimated at 9.3% (95% CI: 4.4%-18.7%). In summary, we showed the contamination rate of C. difficile in Iranian food resources. Also, the prevalence of toxigenic strains in Iranian food resources can be a significant risk to public health. Meanwhile, it seems that C. difficile contamination in Iranian raw meat is more occur in retail than meat processing plants.