Making the World Safe for Antibiotics

Senator Ted Kennedy of Massachusetts recently introduced a bill that would ban all non-therapeutic use of antibiotics in livestock and poultry production. He calls it the Preservation of Antibiotics for Human Treatment Act of 2002. His concern is that using antibiotics in farming creates resistance to antibiotics used for treating humans. However, other industrialized countries have already tried the farmer restriction approach to antibiotics. As we shall see, it has hurt rather than helped.

We do know that doctors and hospitals are encountering antibiotic resistance: some medications that used to kill particular germs no longer do their job. We also know that two major parts of the problem involve people, not animals: First, patients often demand antibiotics (because they have faith in them) even when they’re sick with a virus that no antibiotic can cure. So, about half of human antibiotics are prescribed uselessly. Second, we often forget to keep taking the medicine after our symptoms disappear. If we take only half or two-thirds of the pills many of the toughest bugs will live—and adapt to the antibiotics.

A group called the Alliance for the Prudent Use of Antibiotics issued a report supporting Senator Kennedy’s bill to ban antibiotics in agriculture—except when a sick animal gets a prescription from its veterinarian. (Even Senator Kennedy isn’t willing to let sick pets or cows die when modern medicine could save them.)

The Prudent Use report is not prudent in its use of deceptive phrases. Here are some excerpts from it:

“Because [anti-microbial agents] may contribute significantly to the development of the anti-microbial resistance. . . .”

“Regulatory officials in [other countries] have invoked the precautionary principle” in restricting some agricultural uses of anti-microbials. . . .”

“These practices are implicated in contamination of the environment with resistant bacteria.”

“Studies suggesting that farmers and family members may be more likely than the general population to acquire antimicrobial-resistant bacteria. . . . ” (Emphasis mine.)

In science, as in the courtroom, “maybes” like these mean you can’t prove your case. The Alliance has never found an actual case where the use of antibiotics on farms has been linked to treatment failure in a human patient—but they’re worried. They don’t think they can reform doctors and patients to cut back antibiotic use. So why not reform the farms? How could it hurt?

Denmark banned feed use of antibiotics three years ago. There’s been no reduction in the incidence of antibiotic-resistant bacteria among Denmark’s human patients. However, disease among Danish birds and animals has increased substantially—especially diarrheic diseases among piglets and necrotic enteritis in poultry. The Danes had to increase their use of prescription antibiotics from a prior norm of about 50,000–55,000 units per year to 80,000 units in 2000.

Worse, Danish veterinarians now feel compelled to prescribe amoxicillin, an antibiotic frequently used in treating children, to treat the necrotic enteritis outbreaks in poultry houses.

We have long-term data from Sweden, which banned non-therapeutic farm use of antibiotics in 1986. (They hadn’t found any link to human health, but one of the biggest newspapers in the country had this really scary front-page story.)

Sweden, too, has been disappointed. The first year, post-weaning deaths among little pigs increased 20 percent. As in Denmark, necrotic enteritis started killing the chickens. (The United States hasn’t had a problem with necrotic enteritis since the 1950s.) The tonnage of anti-microbial feed additives nearly doubled, from about 22,000 tons per year in the 1980s to 44,000 tons by 1996.

In Sweden, too, there has been an undesirable shift toward more farm use of antibiotics that are important for treating human disease, replacing previously used antibiotics that were less important to humans.

Apparently, we’re stuck with two basic realities: 1) both doctors and farmers need to use antibiotics judiciously; and 2) we need to encourage pharmaceutical companies to keep finding good new antibiotics. Right now, European governments are imposing price controls on the drug companies, and that discourages research.

During the Clinton administration, the U.S. Food and Drug Administration front office may have violated its own regulations to conspire with anti-antimicrobial advocates. FDA Commissioner Jane Henney thought the issue was a great way for activist government to be seen “saving” the public. But that didn’t do much to encourage the drug companies to find new antibiotics.

Maybe Senator Kennedy could hold a hearing on that problem before borrowing another non-solution from Europe.



This article originally appeared in the Knight-Ridder Tribune on May 23, 2002, and is reprinted with permission.