Where does Yersinia enterocolitica bacteria come from and How does Y. enterocolitica spread?

The CDC couldn’t figure out why, but in June and July 1982, almost 900 people in Mississippi, Tennessee, and Arkansas came down with diarrhea, abdominal pain, and in most cases fever from an infection of Yersinia enterocolitica.

The best guess was that it came from a single milk plant in Memphis that distributed a large amount of pasteurized but nevertheless contaminated milk. The problem with yersinia is that if it is present in large enough numbers, some of it can survive pasteurization. Then it grows well at refrigerator temperatures. This is a bad combination of characteristics in a foodborne pathogen.

By 1990 infections caused by Y. enterocolitica emerged from a widely distributed reservoir (that is, a place where a germ lives more or less permanently) in swine.

Chitterlings, pig intestine, which is often served as a holiday dish by southern Black families, were a source of a large outbreak in Atlanta around Christmas that year. The potential for transmission from food handlers to children is the strongest, so people who prepare chitterlings (this is a labor-intensive and time-consuming process) should not take care of kids while the food is being made.

Y. enterocolitica is a rod-shaped bacterium in the same family as Y. pestis, the germ that causes Black Death. While the main source of the germ is pigs, it is also found in rodents, rabbits, sheep, cattle, horses, dogs, and cats. Children are more susceptible than adults, and the infection is more common in the winter. Fortunately, infection with Y. enterocolitica is not very common: only about 1 in 100,000 people get it each year.

Still, if you’re that one or your kid is, it can be very unpleasant. Most cases simply resolve by themselves without any intervention after a few days of stomach upset. In more severe cases, antibiotics can be used. Very rarely, some people get pains in the knees, ankles, or wrists that can last up to six months.

Some, especially women, can get a rash on the legs and trunk, but it usually goes away in a few weeks. Y. enterocolitica can be avoided if you don’t eat undercooked pork, if you wash your hands after contact with animals or raw meat, and if you are very careful about washing before touching kids or their toys, bottles, or pacifiers.