FDA denounces practice of giving livestock antibiotics to stimulate growth while farm workers are developing antibiotic resistance.

Workers at industrial livestock plants where animals receive antibiotics have developed drug-resistant bacteria in their noses, according to a new study.

The bacteria include Staphylococcus aureus, commonly known as “Staph,” which include the well-known bug MRSA (methicillin-resistant Staphylococcus aureus). The study showed that not only were the bacteria found in the noses of the workers resistant to methicillin, but other antibiotics as well. The researchers tested for genetic markers to indicate the bacteria came from livestock.

The study, conducted by researchers at the Johns Hopkins Bloomberg School of Public Health and others, adds to a four-decades-old debate over the use of antibiotics at industrial farms. The new research, published July 2 in the journal PLOS ONE, focused on workers at industrial livestock plants and well as antibiotic-free farms in North Carolina.

North Carolina ranks second nationally behind Iowa in terms of hog production. The study showed the bacteria present in the noses of the industrial workers, but not in those who work on antibiotic-free farms.

Dr. Christopher Heaney, a professor at Johns Hopkins, told Healthline the debate over antibiotic use in livestock production has raged since a 1976 study. That research showed development of tetracycline resistance in coliforms isolated from the feces of chicken farmers who raised birds that were given the drug in their feed.

“A limitation of our study is that it did not sample animals on the farm,” Heaney said. “However, it does provide information that could contribute to a discussion about antibiotics use in livestock production.”