Real Cause of E. coli Spinach Problem

Two studies in the Journal of Infectious Diseases call the safety of our food supply into question; one uncovers a new bacterial danger, and the other shows that antibiotic use in livestock increases the danger of antibiotic resistance in humans.

The first study implicated Yersinia pseudotuberculosis as the cause of an outbreak of food-borne illness among children in a Finnish town. The bacteria was traced to carrots grown on a single farm. This was the first time this type of bacteria had been recovered from an epidemiologically implicated source of food-borne illness.

Yersinia pseudotuberculosis is a well-known pathogen in wild mammals, and wild animals likely infected the carrots, which were stored for months in open containers.

The bacteria was further spread when the carrots were washed and peeled. The authors of the study called for regulations addressing the production, storage and shipping conditions for fresh produce in order to prevent similar problems.

The second study found that exposing poultry to the antibiotic virginiamycin led to resistant forms of the bacteria E. faecium in humans. After being exposed to virginiamycin, E. faecium from conventional poultry and from patients who consumed poultry became resistant more often.

An editorial commenting on the studies noted that the findings are "examples of how industrialization of food production ... carries and even amplifies risk for unaware consumers."

The Journal of Infectious Diseases November 2006; 194: 1209-1216
The Journal of Infectious Diseases November 2006; 194: 1191-1193
EurekAlert October 3, 2006