The E. coli strain that sickens humans and is generally associated with cattle, has been discovered in swine.

Recent research at Iowa State University (ISU) has shown that E. coli 0157:H7 can be transmitted through the air among swine, even in the absence of direct contact.

Nancy Cornick, an ISU associate professor of veterinary microbiology, who conducted the research for the Food Safety Consortium, previously proved that uninfected pigs sharing pens with infected pigs could also become infected.

Other trials have shown that E. coli 0157:H7 can infect and remain in some pigs’ intestinal tracts for at least two months, signaling that the bacterial organism can colonize swine.

The prevalence of the pathogen in swine remains small, but noteworthy. Cornick says one U.S. slaughter plant recovered E. coli 0157:H7 from 2% of its pigs. The bacterium has also been recovered from healthy hogs in Chile, Japan, the Netherlands, Norway and Sweden.

The USDA’s National Animal Health Monitoring System (NAHMS) conducted swine surveys in 1995, 2000 and 2006, in which they tested 8,660 fecal samples collected from 343 randomly selected swine farms for the presence of virulent E. coli 0157:H7. All samples were negative.

However, some small-scale studies have shown a very low prevalence of the bacterium in U.S. pigs.

Standard processing techniques and proper handling during storage and preparation will prevent contamination of pork products.