Prevalence of Providencia Strains among Patients with Diarrhea and in Retail Meats in Thailand.

In the present study, we examined the prevalence of Providencia spp. in retail meats and in stool samples from diarrheal patients in Thailand. Providencia-specific (Psp)-PCR amplification was positive for 58% (15/26) of the chicken, 64% (16/25) of the pork, and 68% (17/25) of the beef samples. Subsequently, Providencia strains were isolated from 65% (17/26) of the chicken, 68% (17/25) of the pork, and 72% (18/25) of the beef samples. Although P. alcalifaciens (40-58%) was the most prevalent Providencia strain, P. rettgeri, P. stuartii, and P. rustigianii were also isolated. Of the patient stool samples tested, 7.5% (16/214) had Psp-PCR products, of which 4 were P. alcalifaciens (1.9%), 4 were P. rettgeri (1.9%), and 1 was P. stuartii (0.5%). In conclusion, retail meats were substantially contaminated with Providencia, especially P. alcalifaciens. Therefore, retail meats are possibly the source of Providencia infections in humans.