Yersinia pseudotuberculosis infection contracted through water contaminated by a wild animal

We performed epidemiological studies on Yersinia pseudotuberculosis in one valley where a 3-year-old boy had been infected with Y. pseudotuberculosis serotype 4b in December 1982. Y. pseudotuberculosis serotype 4b was isolated from a water sample derived from a mountain stream from which the boy had drunk and from 1 of 41 rats trapped in the upper part of this stream in December 1986. The restriction endonuclease patterns of the plasmids in these isolates showed the rat and patient isolates to be identical but distinct from the water isolate. These data suggest the potential for transmission of Y. pseudotuberculosis through water contaminated by nondomesticated animals carrying this species.