Marshfield, Wis. -- Antibiotic use as a livestock growth promoter increases the risk of human antibiotic resistance, a Marshfield Clinic researcher and his colleagues have found.
Results of the nearly $1.4 million three-year study, funded by the Centers for Disease Control and Prevention, Atlanta, Georgia, are in the November 1 issue of The Journal of Infectious Diseases.
Edward Belongia, M.D., Marshfield Clinic Research Foundation, Marshfield, Wis., and his colleagues examined poultry exposure as a risk factor for antibiotic resistance in Enterococcus faecium, a gut bacterium that is increasingly the cause of infections in hospitals. The investigation team focused on use of a growth-promoting antibiotic, called virginiamycin, in poultry.
Virginiamycin is closely related to quinupristin-dalfopristin, an antibiotic licensed to treat patients with serious, antibiotic-resistant infections. The drug is prescribed under the brand name Synercid. According to Belongia, "There is a relative lack of data on the impact of antibiotic use in livestock and its relationship to antibiotic resistance in humans, but there is a fair amount of indirect evidence suggesting that antibiotic use could pose a risk to human health."
"We've known for a long time that resistant bacteria can be found on retail poultry products, but our study is one of the first to show an association between human carriage of antibiotic resistance genes and eating poultry or handling raw poultry.
"These results indicate that virginiamycin use in poultry leads to transfer of antibiotic resistance genes to human gut bacteria through the food supply and they provide additional evidence that use of growth promoters in animals may have long-term consequences for human health. The Food and Drug Administration (FDA) can use this information to improve its risk assessment procedures."