[Virulence plasmid in Yersinia enterocolitica O:3 of murine origin].

BACKGROUND

Pathogenic strains of Yersinia enterocolitica harbor a virulence plasmid of 45-48 megadalton that can be detected using different techniques. Rodents are important reservoirs of Y enterocolitica.

AIM

To investigate the carrier status of Y enterocolitica in murine rodents.

MATERIAL AND METHODS

Two hundred sixty-one mice and rats were captured in rural and urban areas of Valdivia. Y enterocolitica was cultured from viscera and fecal homogenates. Virulence plasmids were detected using crystal violet binding.

RESULTS

Thirteen Y enterocolitica strains were isolated from 11 rodents. Ten strains belonged to the biotype 1 and three to the biotype 4, serotype O:3. The most frequently infected rodent species were R norvergicus (20%), followed by A longipilis (11%), A olivaceus (2%) and O longicaudatus (2%).

CONCLUSIONS

Rodents, and specially the domestic rat, can be an important source of Y enterocolitica infection for human and susceptible animal species.