Chickens On Drugs

Antibiotics fed to chickens are creating superbugs that even our strongest medicines can't cure. Read this before you make dinner tonight.

When you're doubled over with food poisoning, you'd swear you did something odious in a past life to deserve it. The diarrhea, vomiting and cramping usually come courtesy of the bacteria that dwell in the guts of the animals that end up as dinner. If your condition is severe, you'll probably call the doctor, who may jot you a prescription for Cipro, an antibiotic in the fluoroquinolone family. This powerhouse drug is effective against three of the most common strains of foodborne bacteria and is a chief weapon against campylobacter, the number-one cause of food borne illness in this country. Campylobacter leads to more than 2 million cases of food poisoning and 100 deaths each year, according to the Centers for Disease Control and Prevention in Atlanta. Doctors are so eager to quell the symptoms that they often prescribe Cipro—which has always been a reliable cure—without waiting for campylobacter test results, which can take days.

That's why experts are alarmed that the bacteria, most commonly found in poultry, is gaining on Cipro. It's estimated that more than 9,200 people who contracted campylobacter from poultry in 1999 didn't respond to Cipro or similar drugs, according to a recent report by the FDA Center for Veterinary Medicine in Rockville, Maryland. If Cipro fails, your doctor may do a trial and error with other drugs, one of which should work. The cost to you? You will be sicker, longer.

For years, scientists have warned that bacteria are becoming impervious to antibiotics, a phenomenon known as antibiotic resistance. First they blamed doctors who over prescribed the drugs and patients who didn't finish a full course, both of which promote resistance. Now there's significant evidence that farm animals are a breeding ground for resistant germs.

Back at the ranch. What your food has been eating is probably the last thing you ponder as you bite into your grilled-chicken sandwich. But antibiotic resistance has its beginnings in an animal's diet. At the typical U.S. poultry farm, some 20,000 birds are crammed into a 40-foot-by-400-foot "growing house" and routinely given feed laced with low doses of antibiotics such as tetracycline to keep them healthy and plump. If some chickens show signs of illness, all 20,000 may be nipple-fed water spiked with Baytril, a fluoroquinolone antibiotic closely related to Cipro.

The problem is, the drugs don't only home in on the bacteria that are making the birds sick, explains Rebecca Goldburg, Ph.D., a senior scientist at Environmental Defense, a non-profit advocacy group in New York City. Rather, the antibiotic affects other bacteria in a chicken's digestive system, such as campylobacter. These bacteria don't make the birds ill, but they can sicken people who eat the poultry if it is improperly handled or under cooked. (There is little to no risk of contracting the campylobacter bacteria from eggs.) As with all bacteria, the more these strains are exposed to an antibiotic, the easier it is for them to develop resistance. Translation: Antibiotics won't work when you need them the most. "We're promoting resistance to what is often the antibiotic of last resort," warns Stuart Levy, M.D., author of The Antibiotic Paradox (Perseus Publishing).

Endangered medicine. It's the reliance on Baytril that has some public health experts worried as of late. "The number of resistant campylobacter has risen since Baytril's approval in 1996," says Tamar Barlam, M.D., director of the Project on Antibiotic Resistance at the Center for Science in the Public Interest in Washington, D.C. In lab tests, 19 percent of campylobacter germs are now resistant to Cipro, Baytril's cousin. "It's a public health concern," she says. The issue is so pressing that in 2000, the FDA proposed to withdraw approval for the use of fluoroquinolones like Baytril in poultry. (Fortunately, campylobacter's resistance to Cipro does not diminish the drug's power over anthrax.)

Can farmers fix the problem?. Animals that are sick need treatment, of course. But it turns out that an estimated 70 percent of all antimicrobials (antibiotics and drugs that fight parasites and fungi) are used on healthy animals. "There are diseases, such as those resulting from extreme weather changes, that we know will occur," argues Ron Phillips of the Animal Health Institute in Washington, D.C., which represents makers of animal-health products. "It's important that [farmers be] able to fight the bacteria. That's part of what goes into having a safe food supply."

Not necessarily, say some public health advocates. "In many cases, antibiotics are used to mask the effects of poor sanitation," says Margaret Mellon, Ph.D., director of the food and environmental program for the Union of Concerned Scientists in Cambridge, Massachusetts. Experts are not suggesting that all American farmers go organic. "It's just a matter of cleaning up their act," says Dr. Barlam. In parts of Europe, she says, where the use of certain antibiotics in healthy animals is restricted, farmers have better methods of keeping animals healthy: "They disinfect the houses between flocks and are careful about keeping out rodents and other carriers of disease."

The American poultry industry takes issue with the argument that antibiotics cover up the effects of dirty coops. "I'd say we're doing a good job of raising healthy animals in good conditions," says Richard Lobb of the National Chicken Council in Washington, D.C. "Low levels of preventive antibiotics keep flocks healthier, which allows us to produce a lot of protein at an attractive price." Data from Europe, however, shows that restricting fluoroquinolone use needn't push up the price of poultry. "In Denmark, where the use of fluoroquinolones has been restricted since 1997, the cost of poultry has remained the same," says Environmental Defense's Goldburg

Baytril's maker, Bayer, is exhibiting its own form of resistance. In response to the FDA, Bayer filed a report with the organization in 2001, concluding "there is no evidence that withdrawal of [Baytril] would have a meaningful impact on resistant campylobacter infections in humans." Bayer continues to defend itself in an ongoing FDA review.

Battling resistance. The good news? Lawmakers in Congress recently proposed legislation that would ban the use of Cipro-related drugs in poultry and phase out the non therapeutic (preventive) use of other medically important drugs. "Study after study has shown a direct link between the use of antibiotics...in animals and the rise of dangerous infections in human beings that are resistant to these medications," says Senator Edward M. Kennedy (D-Mass.), who sponsored the Senate version of the bill.

If antibiotic abuse continues, health professionals may not be able to treat even the simplest of diseases. "Before the 1940s, antibiotics weren't available, and a small cut on your arm that became infected could become lethal,"Goldburg says. "Unless we preserve the power of the antibiotics we have, we may be heading back in that direction."

Serving up some caution. Until laws preventing antibiotic abuse are in place, what's a chicken eater to do? Be selective, choosing certified organic meats, which are by definition antibiotic-free, or those labeled "raised without antibiotics." Perdue, ConAgra Poultry, Foster Farms, Tyson Foods and Gold Kist have stopped using Baytril in their chickens. You can also patronize restaurants that refuse to buy Baytril-treated chicken. These include Subway as well as Carl's Jr., Dairy Queen, Hardee's, McDonald's and Wendy's (just tell them to "hold the fries"). "There's a growing demand for antibiotic-free chicken, and the industry is listening," says Dr. Barlam. "I'm optimistic."

Lori Miller Kase writes on health issues and lives in Simsbury, Connecticut.