Elastic Light Scatter Pattern Analysis for the Expedited Detection of Yersinia Species in Pork Mince: Proof of Concept.

Stephen L W On,Steve Flint,Yuwei Zhang,Andrew Gehring,Valery Patsekin,James Lindsay,Graham C Fletcher,J Paul Robinson,Venkata Chelikani,Haoran Wang,Craig Billington

doi:10.3389/fmicb.2021.641801

Abstract

Isolation of the pathogens Yersinia enterocolitica and Yersinia pseudotuberculosis from foods typically rely on slow (10–21 day) “cold enrichment” protocols before confirmed results are obtained. We describe an approach that yields results in 39 h that combines an alternative enrichment method with culture on a non-selective medium, and subsequent identification of suspect colonies using elastic light scatter (ELS) analysis. A prototype database of ELS profiles from five Yersinia species and six other bacterial genera found in pork mince was established, and used to compare similar profiles of colonies obtained from enrichment cultures from pork mince samples seeded with representative strains of Y. enterocolitica and Y. pseudotuberculosis. The presumptive identification by ELS using computerised or visual analyses of 83/90 colonies in these experiments as the target species was confirmed by partial 16S rDNA sequencing. In addition to seeded cultures, our method recovered two naturally occurring Yersinia strains. Our results indicate that modified enrichment combined with ELS is a promising new approach for expedited detection of foodborne pathogenic yersiniae.

Highlights

In industrialised nations, yersiniosis is most frequently associated with infection by either Yersinia enterocolitica or Yersinia pseudotuberculosis and is typified by sequelae including diarrhoea and acute, severe abdominal pain that may resemble appendicitis (Rosner et al, 2013; BancerzKisiel and Szweda, 2015); fatalities may occur (ECDC, 2019)
The methods most commonly recommended for detection of yersiniae in foods (Weagant et al, 2017) exploits their ability to grow at lower temperatures than competing microflora; this “cold enrichment” approach requires a 10–21 day incubation period that is unsuited for rapid response to a suspected outbreak
The resulting cross validation (CV) matrix used for identification performed close to the ideal specifications, with results for Y. pseudotuberculosis somewhat below the desirable 90 metric (Table 2)

Summary

Introduction

Yersiniosis is most frequently associated with infection by either Yersinia enterocolitica or Yersinia pseudotuberculosis and is typified by sequelae including diarrhoea and acute, severe abdominal pain that may resemble appendicitis (Rosner et al, 2013; BancerzKisiel and Szweda, 2015); fatalities may occur (ECDC, 2019) These species represent a significant burden of gastrointestinal disease in Europe (ECDC, 2019), New Zealand (Pattis et al, 2019), and the United States (CDC, 2019). Transmission is most commonly associated with the Detection of Yersinia Using ELS consumption of contaminated food, with pork a frequently mentioned source for Y. enterocolitica in particular (Fois et al, 2018; CDC, 2019; ECDC, 2019) Both Y. enterocolitica and Y. pseudotuberculosis infections and outbreaks have been attributed to the consumption of raw or contaminated vegetables such as carrots, spinach and lettuce (MacDonald et al, 2016; Williamson et al, 2016). Better methods for isolation and detection are warranted for improved public health actions

Methods

Results

Conclusion