Faced with mounting evidence that the routine use of antibiotics in livestock may diminish the drugs' power to cure infections in people, the Food and Drug Administration has begun a major revision of its guidelines for approving new antibiotics for animals and for monitoring the effects of old ones.
The goal of the revision is to minimize the emergence of bacterial strains that are resistant to antibiotics. Such resistance makes them difficult or impossible to kill.
Drug-resistant infections, some fatal, have been increasing in people in the United States, and many scientists attribute the problem to the misuse of antibiotics in people and animals. Of particular concern to scientists is that recent studies have found bacteria in chickens that are resistant to fluoroquinolones, the most recently approved class of antibiotics and one that scientists had been hoping would remain effective for a long time.
A component of the new guidelines will be the requirement that manufacturers test new livestock drugs for a tendency to foster the growth of resistant bacteria that could prove harmful to people. Testing will be required before and after a drug is approved.
The types of antibiotics that would get scrutiny are those that are also used by humans or are related to drugs used by humans. If the antibiotics are shown to foster bacterial resistance, they could be banned from use as growth promoters in animals. If scientists became aware of a problem with older antibiotics, they too could be banned.
Of the 50 million pounds of antibiotics produced every year in the United States, about 40 percent is given to animals, mostly as feed additives to promote growth.
The drug and agriculture industries say the FDA is going too far toward restricting access to antibiotics, which they insist are essential to produce safe and affordable meat and poultry. The industries also say the proposed rules will make drug development more difficult and expensive.
But public-health and consumer advocates, as well as some scientists, say the FDA is not going far enough, because antibiotics are a precious medical resource that should not be squandered to fatten animals. A coalition of 37 groups, led by the Center for Science in the Public Interest, a nonprofit group based in Washington, will petition the FDA tomorrow to separately rule that if a drug is used to treat diseases in people, it can no longer be given to animals as a growth promoter.
Pub Date: 3/08/99