Antibiotic Misuse in Animals Hurts Human Health

Publication: Statesman Journal (OR)

Author: Dr. Shelley Hearne and Dr. Stuart B. Levy


02/28/2009 - The U.S. Centers for Disease Control and Prevention is working to build public awareness regarding the dangers of people overusing antibiotics. Misuse and overuse of antibiotics—important drugs that kill bacteria or suppress their reproduction—is linked to an increasing number of antibiotic-resistant infections.

The CDC's public awareness campaign is laudable: If people do not have a bacterial infection, they should not take antibiotics. For example, patients shouldn't insist on receiving antibiotics for common colds—which are caused by viruses, not bacteria. As antibiotic misuse increases, germs become resistant to the drugs, and crucial disease-fighting tools become useless.

Yet the CDC's campaign is missing an import issue: antibiotic misuse in animals.

Half or more of the antibiotics produced in the United States are not used in people. Instead, most are given to food animals—in non-therapeutic doses, or amounts too low to actually fight disease—often simply to increase the animals' growth rate. Numerous studies connect this practice to a rise in antibiotic-resistant, harmful strains of E. coli, salmonella, and campylobacter.

Research is ongoing into whether the practice also is linked to the emergence of strains of methicillin-resistant Staphylococcus aureus, or MRSA, which in 2005 was estimated to have caused 50 deaths in the U.S. every day.

A truly effective push to address the rise of "superbugs" thus must also include changing national policies to end the inappropriate and non-therapeutic use of antibiotics in "factory farms," or large-scale livestock feeding operations.

Until the mid-20th century, bacterial infections routinely led to serious illness and often death. It is no exaggeration to say that the discovery of drugs that could cure infections has, over the past few generations, been a boon to human health—and to veterinary medicine when the drugs are properly administered to sick animals.

Antibiotic resistance, though, is a dangerous trait that enables bacteria to survive and continue to grow instead of being inhibited or destroyed by therapeutic doses of the drug. Since antibiotic resistance is on the rise, one of the great medical miracles of all time is at risk.

The CDC and other groups report that antibiotic overuse in animals helps generate resistant bacteria in their intestinal tracts. The bacteria can then be found on meat and other animal products, as well as in animal fecal waste that is spread onto fields as fertilizer. This last point is important, since drugs that are discharged into the environment can continue to lead to development of resistant bacteria.

Farm workers face the most direct risks, but consumers also can be exposed to drug-resistant bacteria if they handle or consume raw or undercooked meat or other foods.

The CDC is not alone in noting that the way we raise our livestock squanders the effectiveness of life-saving medicines. The U.S. National Academies of Science and World Health Organization support efforts to change this practice, while the European Union already has banned it.

Proposals that would phase out the misuse of important classes of human antibiotics in farms have, however, languished in Congress for years. The U.S. Food and Drug Administration came close to shutting down this unnecessary practice 30 years ago, but farm and pharmaceutical lobbyists blocked the effort and have maintained as strong a hold on the status quo as they have on their profit margins. Meanwhile, medicines we rely upon to battle deadly illnesses, such as pneumonias and blood-borne infections, become less useful year by year.

Last summer, Congress took a first step by mandating that pharmaceutical companies report the quantities of antibiotics they sell for agricultural use. Yet industry lobbyists fought off requirements that the drug makers disclose crucial details, such as which drugs are used, in what quantity for each farm animal, and how often. So while government agencies and legislative bodies work on ways that people can reduce antibiotic resistance in homes and hospitals, they remain in the dark about where and how much antibiotics are overused.

It is long past time for the federal government to address the rise of drug-resistant germs where they are most readily found and bred.

Shelley Hearne is the managing director of the Health and Human Services Policy Program at The Pew Charitable Trusts.

Stuart B. Levy is the director of the Center for Adaptation Genetics and Drug Resistance at Tufts University School of Medicine, and president of the Alliance for the Prudent Use of Antibiotics.

X
(All Fields are required)