Why do modern bacteria "resist" antibiotics, confounding medical treatment?

--Hugo Mestres, Seattle, WA

Antibiotics have played a profoundly important role in staving off bacterial infections since Alexander Fleming first discovered them in 1927. But the effectiveness of these so-called miracle drugs has waned in recent years as some of the very bacteria they are meant to control have been mutating into new forms that don’t respond to treatment. Many medical experts blame this phenomenon on both the misuse and overuse of antibiotics in recent years in both human medicine and in agriculture.

 

Doctors first noticed antibiotic resistance more than a decade ago when children with middle ear infections stopped responding to them. Penicillin as a treatment for strep has also become increasingly less effective. And a recently-discovered strain of staph bacteria does not respond to antibiotic treatments at all, leading medical analysts to worry that certain "super bugs" could emerge that are resistant to even the most potent drugs, rendering some infections incurable. The U.S. Centers for Disease Control and Prevention (CDC) calls antibiotic resistance one of its "top concerns" and "one of the world’s most pressing health problems."

 

One large part of the problem, according to the CDC, is the tendency for people to take antibiotics to fight viruses, which they cannot do. Antibiotics fight bacteria, not viruses, and will not fight colds, flu, bronchitis, runny noses, or sore throats not due to strep. Nonetheless, says CDC, "more than 10 million courses of antibiotics are prescribed each year for viral conditions that do not benefit from antibiotics." To address this, a growing number of doctors, including Dr. Randel Cardott, an internist with Iowa’s Genesis Convenient Care, are advocating a "wait-and-see" approach to prescribing antibiotics, especially in cases like middle ear infections that sometimes prove to be viral and not bacterial in origin. Cardott says that European physicians have taken this approach for years with no adverse effects.

 

Scaling back on antibiotics for human maladies won’t address the whole problem. Farmers and ranchers use antibiotics heavily, too. In North America, industrial beef, pig and poultry farming is a big unsanitary business, and antibiotics are used extensively to ward off diseases and also for non-medical reasons, such as to promote growth. In fact, the Union of Concerned Scientists (UCS), a non-profit research and advocacy group, estimates that some 70 percent of all antibiotics are used as additives in the feed given to healthy pigs, poultry and cattle. These drugs leave the animals’ bodies as waste and work their way into local water supplies, as well as right into the food chain. "Nonetheless," says UCS, "agribusiness and the pharmaceutical industry are fighting hard to thwart restrictions on the use of antibiotics in agriculture."

 

Keep Antibiotics Working, a non-profit dedicated to reducing antibiotics overuse in agriculture, advocates phasing out unnecessary antibiotics in healthy livestock and poultry. In lieu of Congressional action along these lines, the group is encouraging meat wholesalers and retailers to voluntarily stop buying or selling meat that has been produced using antibiotics for purposes other than treating sick animals. Consumers looking to avoid antibiotics in meat should seek out organic offerings at natural foods markets.

 

CONTACTS: UCS, www.ucsusa.org/food_and_environment/antibiotics_and_food/; Keep Antibiotics Working, www.keepantibioticsworking.com.

 

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