Thursday, November 24, 2011

Antibiotic Use On Farms Linked To Rising Rates Of Drug-Resistant Infections

As families across America adorn their dinner tables with plump, juicy turkeys this Thursday, they've likely given little thought to what their future food previously consumed.

By the end of this year, an estimated 248 million turkeys will have been raised in the U.S., approximately 83 percent on farms that produce more than 60,000 turkeys each and most eating a diet that includes low doses of antibiotics. This common agricultural practice results not only in more meaty birds, according to experts, but also in greater risks to public health.

"Antibiotic use in animals comes back to haunt people," said Stuart Levy, a Tufts University microbiology professor who focuses on antibiotic resistance. He recently co-authored a review of the evidence showing how animal antibiotics affect human health -- via direct contact and indirectly via food, water, air and anywhere manure goes.

Levy and other experts warn that the widespread use of antibiotics to treat sick livestock, prevent the spread of disease in cramped conditions or simply promote animal growth has fueled the proliferation of antibiotic-resistant bacteria, which is making many infections in humans harder to treat. As The Huffington Post reported in August, some human infections now resist multiple antibiotics.

Livestock receive an estimated 80 percent of the nation's antibiotics. According to the U.S. Food and Drug Administration, about 90 percent of those antibiotics are consumed by the animals in their feed or water -- usually at very low doses. What doesn't kill bacteria, however, often makes them stronger and more likely to defeat medicine's current range of weaponry.

"Turkey is one of the most frequently contaminated meats," said Ellen Silbergeld, a professor at Johns Hopkins School of Public Health. She highlighted a study from earlier this year that found 77 percent of turkey samples collected from U.S. supermarkets tested positive for the bacteriaStaphylococcus aureus. Of those, approximately 96 percent were resistant to at least one antimicrobial agent. A few of other recent studies hint at the growing problem of multidrug-resistant infections, such as methicillin-resistant Staphylococcus aureus (MRSA), in meats sold to consumers, including turkey.