An Ohio State University research team lead by Thomas Wittum, professor and chair of Veterinary Preventive Medicine, made the first discovery of a carbapenem antibiotic-resistance gene on a U.S. livestock farm. Antibiotic resistance is a large concern for both human and animal health. In this article, we answer your questions about this discovery, pig farming and pork.
1. Is the U.S. pork supply safe?
Yes, the U.S. pork supply is safe, and no pork was contaminated. The resistant gene identified in the study was not found in a market hog, and there was no threat to food safety.
2. Where was the discovery made?
The Ohio State University research team clearly states the discovery of the antibiotic-resistant gene was found in farrowing and a nursery barn on a 1,500 unit sow farm. Even though this particular hog farm is a farrow-to-finish operation, the resistant gene was not identified in the finishing barns where market hogs are raised.
3. What antibiotic-resistant gene was found?
The Ohio State research team found the transmissible carbapenem-resistant enterobactericeae (CRE), a bacteria carrying a rare gene that hinders carbapenems, a class of antibiotics used to fight germs that have already become resistant to other drugs. Carbapenems are never used in animals intended for food, but other types of beta-lactam antibiotics, such as cephalosporins, are sometimes used on farms to treat sick animals under veterinary supervision.
4. What is the big deal about CRE?
The U.S. Centers for Disease Control and Prevention considered CRE as an “urgent” public health threat because this multidrug-resistant bacteria has been found in hospitalized patients. While finding CRE at a livestock farm is definitely concerning, the resistant gene was found in an environmental sample from farrowing and nursery and not in feces of market hogs. The conclusions of the study are drawn based on this one barn result without further validation, replication and research, and demonstrate this issue requires additional study.
5. So, how did the resistant gene get on the farm?
As stated by the researcher, resistant gene samples were found in one barn, on one site without any confirmed indication of how the resistant gene got there. Ohio State University researchers acknowledge that it is unknown how CRE bacteria were introduced to the facility and that it could have been introduced by an outside source. The fact that CRE was found in one area of the farm indicates that current internal biosecurity measures are effective.
6. Why do pig farmers use antibiotics?
America’s pig farmers use antibiotics after consultation with their herd veterinarian in the context of the veterinary-client-patient relationship to help prevent, control or treat disease in their pigs. If needed, producers use antibiotics responsibly, under veterinarian supervision and consistent with the Food and Drug Administration and Pork Quality Assurance Plus guidelines.
7. What does the pork industry have to say about this?
According to the National Pork Board, an important takeaway from the study is that the U.S. pork supply is safe. The resistant gene identified in the study was not found in a market hog, and there was no threat to food safety. The U.S. pork industry supports efforts to monitor for the occurrence of this type of isolated incident. Pig farmers in many states voluntarily participate in the Ohio State University’s Public Health Preparedness for Infectious Diseases Program. These producers take part in this research to better understand emerging disease issues. The NPB agrees that more studies need to be performed to validate and attempt to replicate the finding. The NPB looks forward to learning more about ongoing surveillance efforts that protect human and animal health.