Identification of Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus, Bacillus subtilis, and Clostridium perfringens in hospital food.

Despite conducting studies to investigate food contamination in hospitals in different parts of Iran in recent years, there have been no reliable studies to identify Salmonella enteritidis, Salmonella typhimurium, Bacillus cereus, Bacillus subtilis, and Clostridium perfringens in hospital food in Mashhad. Therefore, this study was conducted with the aim of investigating some major foodborne pathogens in hospital food. In this study, 360 food samples were randomly selected from 12 different menus from 13 hospitals affiliated with Mashhad University of Medical Sciences, Mashhad, Iran. Microbial culture methods for the recovery/isolation or enumeration of Salmonella spp., Bacillus spp. and C. perfringens as well as toxinotyping of C. perfringens using the PCR method were performed. B. cereus and C. perfringens were detected in 4 out of 360 food samples, 2 (0.55%) of which were B. cereus and, the remaining 2 (0.55%) were C. perfringens; B. subtilis was not detected in any of the food samples. Furthermore, Salmonella was found in 21 (5.82%) food samples, 12 (3.33%) of which were S. typhimurium, 4 (1.11%) were S. enteritidis, and 5 (1.38%) belonged to other Salmonella species. The most contaminated foods were salad, kebab, and rice samples, which accounted for 36%, 16%, and 12% of the contaminated foods, respectively. In our study, two strains of S. typhimurium and S. enteritidis, were the primary causative agents of food contamination among the investigated pathogens. More stringent control measures should be implemented in hospital catering, particularly for unprocessed foods such as salads.