Isolation of Enteropathogenic Yersinia from Non-human Sources

Abstract

Isolation of enteropathogenic Yersinia from non-human sources is tricky, laborious and time consuming especially due to the small number of pathogenic Yersinia in asymptomatic carriers and the large number of psychrotrophic bacteria in food and environmental samples. Several different methods have been applied for isolation of Yersinia enterocolitica from non-human samples. Direct plating on selective agar plates is useful for detection of high levels (>104 CFU/g) of Yersinia in the sample. Enrichment in high-selective broth is needed for isolation of Y. enterocolitica from food and environmental samples. Cold enrichment at 4°C for 1–3 weeks is suitable for simultaneous isolation of Y. enterocolitica and Yersinia pseudotuberculosis especially when animal carriers are studied. So far, no efficient methods are available for isolation of enteropathogenic Yersinia in food and environmental samples. Thus, PCR is a useful method to use in parallel with culture methods to screen enteropathogenic Yersinia in food and environmental samples. Accurate identification of Yersinia strains is crucial for epidemiological studies. However, phenotypic tests are not sufficient for correct identification of enteropathogenic Yersinia spp. Thus, effort should be made to develop better methods for isolation and accurate identification of enteropathogenic Yersinia from non-human samples.