Bacteria carrying a gene that grants resistance against a powerful antibiotic have been found on a pig farm in the United States, researchers reported this week in the journal Antimicrobial Agents and Chemotherapy.
The rare gene helps bacteria thwart carbapenems, a class of antibiotics used to fight germs that have already become resistant to other drugs. It was located on pieces of DNA called plasmids, which can be swapped between species. This is the first time that bacteria with transmissible carbapenem resistance have shown up in US livestock.
The good news is that these germs (a group known as carbapenem-resistant Enterobacteriaceae, or CRE) didn’t appear in any of the poop samples taken from pigs scheduled for slaughter. So it doesn’t seem likely that they contaminated any pork from the farm.“The concern is that bacteria with this gene on this plasmid could be carried by the pigs into the food supply, where consumers could be exposed and colonized,” says coauthor Thomas Wittum of the Ohio State University College of Veterinary Medicine. “We found no evidence that was happening at this farm, but we want to figure out how to be sure that doesn’t happen.”