Avian-flu concerns push bans on drugs for animals

Roger Harvey wants to wean pigs off of antibiotics.

The drugs have been widely used to fend off E. coli bacterial infections, which may sicken or kill young pigs. Dr. Harvey, a veterinarian at a US Department of Agriculture research lab in College Station, Texas, has developed a drug-free alternative - a friendly bacteria that he says would essentially "vaccinate" piglets against E. coli. Field trials on thousands of pigs at five farms with E. coli problems have shown the treatment to be effective and cost-saving for farmers. If the government grants approval, as expected, the bacterial treatment could be on the market in two or three years, Harvey says.

Finding alternatives to antibiotics has become more urgent as concerns grow that their use in farm animals builds up resistance in bacteria, ultimately creating new "super bugs" that can defy the antibiotics used to treat humans. For this reason, groups such as the American Medical Association and World Health Organization have opposed the use of antibiotics in healthy livestock for some time.

Last month, the Food and Drug Administration (FDA) proposed a prohibition on antiviral drug use in farm animals, saying that practice could lessen the drugs' effectiveness against avian flu. Medical authorities worry that avian flu, now spreading among birds worldwide, may mutate into a form that will pass between humans.

Though the principle of built-up resistance is the same with both antibiotic and antiviral drugs, the FDA has not demanded less use of antibiotics in livestock.

But the industry has begun to act on its own. Earlier this year, four major chicken producers told USA Today that they had voluntarily reduced their use of antibiotics. One of them, Tyson Foods, announced that in 1997 it had used 853,000 pounds of antibiotics on its chickens. In 2004, it used just 59,000 pounds, a 93 percent reduction.

"I think we're seeing a really strong commitment and some action being taken on the part of the major poultry producers," says John Balbus, director of the health program at Environmental Defense, an environmental advocacy group in Washington D.C. "Does that mean the battle is over? Absolutely not."

The US government doesn't require farmers to report their use of antibiotics, so figures are difficult to confirm independently. Several estimates put the total use at between 20 million and 30 million pounds every year, most of it put into animal feed. About 13 million pounds of those drugs are also used by humans, says David Wallinga, a medical doctor and director of the food and health program at the Institute for Agriculture and Trade Policy (IATP), an advocacy group for ecologically sound agriculture. "The vast majority of antibiotics use in animals is unnecessary," Dr. Wallinga says. For decades, he says, they have been used to promote animal growth and prevent disease outbreaks in addition to treating disease.

Environmental Defense and the IATP are part of a coalition of some 300 health, consumer, agricultural, and environmental groups called Keep Antibiotics Working: The Campaign to End Antibiotic Overuse. The coalition supports passage of legislation that would phase out the use of eight classes of antibiotics in farm animals except to treat disease. The bill, sponsored by Sen. Olympia Snowe (R) of Maine, would also authorize the government to collect statistics on antibiotic use in farm animals.

The FDA has acknowledged that antibiotic resistance is a problem, but it has been slow to act. Its proposal to ban the use of two types of antiviral drugs in chickens, turkeys, and ducks, however, came about quickly. Those drugs - developed to treat human cases of influenza - have never been approved for use in animals. But veterinarians are permitted to use them "extra-label" - for purposes other than those on their labels. The FDA ban aims to preserve the drugs' effectiveness in treating avian flu in humans. It is inviting comments on the proposed rule until May 22.

Last year, Chinese authorities admitted they used an older antiviral drug called amantadine to control or prevent avian flu outbreaks on chicken farms, but now say they have stopped the practice. Bird flu strains in Asia had begun to show resistance to amantadine.

Conceptually, the FDA is doing "the exact same thing" as banning antibiotics when it bans antivirals, Dr. Balbus says. "It's a recognition that massive use in agriculture of antimicrobial agents fosters the development of resistance in those animals and that there certainly are pathways between our agricultural animals and human populations."

The FDA has conceded that it knows of no use of antiviral drugs by American farmers but is taking the step as a precaution.

American poultry producers "have no interest" in ever using antiviral drugs, says Richard Lobb, a spokesman for the National Chicken Council. "If we have an avian flu problem, we're not going to medicate the birds [with antivirals]. We're going to destroy them. That's our policy. The first order of business is to stamp out [avian flu] and prevent it from spreading to other flocks. And the only way to do that is to destroy the birds on that farm. So that's what will be done."

But antiviral drugs have been used already on horses to treat equine influenza, says Steve Roach, food safety program manager for the Food Animal Concerns Trust, a member group of the Keep Antibiotics Working coalition. "So it's not just a totally theoretical fear. Right now, we're just depending on [farmers'] good faith that they're not using them."

The Chicken Council also sees no need for legislation to ban antibiotics. "The trend has been toward lesser use of antibiotics over the years as flock health has improved and general animal husbandry, housing, and so forth of animals was improved," Mr. Lobb says. "All [antibiotic] usage within the industry is in accordance with FDA guidelines.... We think that is the appropriate way to go rather than the legislative route."

You've read  of  free articles. Subscribe to continue.
QR Code to Avian-flu concerns push bans on drugs for animals
Read this article in
QR Code to Subscription page
Start your subscription today