[Comparison of Yersinia enterocolitica strains isolated from swine and humans in Guipuzcoa].

Yersinia enterocolitica biotype 4, serotype 3 is a pathogenic bacteria for men. Its most likely reservoir are pigs. We have compared 48 Y. enterocolitica serotype 0:3 strains isolated from pig's tonsils samples as well as porcine-derived food with 301 Y. enterocolitica serotype 0:3 isolate from human stool's samples. All strains are positive for virulence tests. Yersinia enterocolitica serotype 0:3, biotype 4, phage-type VIII was nearly the only single pathogenic strain isolated from both origins in our county. Human and porcine strains showed a similar percentage of chloramphenicol and cotrimoxazol resistance. This pattern of resistance is not common among Y. enterocolitica strains isolated outside of our geographic area. The nearly identical patterns of human and porcine strains, as well as the high frequency of isolation from pig's tonsils (49.5%) and uncooked meal (12.9%) confirm the hypothesis that pigs are the most likely reservoir for human infections in our county.