Genotypic and Phenotypic Characteristics of Yersinia enterocolitica Isolated from the Surface of Chicken Eggshells Obtained in Argentina

Abstract

The prevalence of Yersinia enterocolitica on chicken eggshell surfaces in San Luis, Argentina, was investigated. The pathogenic potential of recovered isolates was assessed by means of phenotypic virulence tests and the presence of the 72-kb pYV plasmid. Antimicrobial susceptibility was determined by the agar diffusion method. DNA digested with XbaI was analyzed by pulsed-field gel electrophoresis (PFGE), and relationships between genomic DNA profiles were established. Eight Y. enterocolitica B2 O:9 strains were recovered after enrichment, for a prevalence of 2.27%. All strains harbored the virulence pYV plasmid, bound Congo red, grew in a low-calcium medium, and autoagglutinated at 37 degrees C. They lacked pyrazinamidase activity and did not hydrolyze esculin. These Y. enterocolitica strains were susceptible to amikacin, ciprofloxacin, chloramphenicol, and trimethoprim-sulfamethoxazole and were resistant to rifampin. According to the genomic DNA patterns obtained by PFGE, the isolates clustered into two groups, I and II. The highest similarity coefficient observed between Y. enterocolitica strains was 0.947. Microbiological controls on production stages of eggs and good culinary practices are necessary to reduce the risk of Y. enterocolitica infection for consumers.

Bacterial contamination of table eggs and the influence of housing systems

“…The organism was isolated from the shell of 14 out of 101 (13.9%) eggs, but not from the albumen or yolks. Favier et al (2005) evaluated a total of 352 eggs for the presence of Yersinia enterocolitica strains on the eggshell. No isolates were obtained by direct culture; however eight Y. enterocolitica strains were recovered after enrichment, which represents a prevalence of 2.27% eggshell samples.…”

Genotypic diversity and pathogenic potential ofYersinia enterocoliticabiotype 2 strains isolated in Brazil

“…Additionally, Y. enterocolitica biotype 2 (B2) strains are the second most frequently reported bio‐serotype found in humans and have also been isolated from animals, humans, food and the environment in different countries, after bio‐serotype 4/O:3 strains (Favier et al . ; Falcão et al . ; Fredriksson‐Ahomaa et al .…”

Yersinia enterocolitica: Epidemiological Studies and Outbreaks

“…Furthermore, Sakai et al [34] reported an outbreak of food poisoning by Y. enterocolitica serotype O:8 in Japan where salad was proposed the cause of infection. Recently, Y. enterocolitica 2/O:9 has been isolated from chicken eggshell surfaces in Argentina [114]. Contamination of the egg surface might have occurred from contact with other Y. enterocolitica -contaminated animal products, such as pork product, during collection on farms or during transportation or handling in retail shops.…”