“An update now on a story we’ve been following closely about a health risk most people don’t know about — farmers feeding antibiotics to healthy animals just to spur their growth. Congress urged them this week to stop doing that because overuse of antibiotics in animals is creating new, drug-resistant strains of bacteria that can spread to humans.”

That was CBS Evening News anchor Katie Couric’s lead-in to a July 16 report.

But Couric is not alone; most major newspapers, including USA Today, the New York Times and the Wall Street Journal, have had something to say about antibiotic use in food-animal production in recent months.

New to the debate is the U.S. Food and Drug Administration’s draft guidance on antibiotic use in food-animal production, released June 28. The House Energy and Commerce Subcommittee on Health held hearings last month, and bills are lingering in the House and Senate that would ban antibiotic use in food animals that prevent or control diseases and improve feed efficiency and weight gain.

A 60-day comment period on the draft will end late this month. “This is the beginning of the process. We will look closely at all the comments,” says William Flynn, senior advisor for science policy at FDA’s Center for Veterinary Medicine.

While the guidance doesn’t have the force of law, it could be used to develop public policy.

One principle of FDA’s guidance is that “the use of medically important antimicrobial drugs (those associated with human use) in food-producing animals should be limited to uses that are considered necessary for assuring animal health.”

This speaks to growth promotion and improved feed efficiency, which FDA cites as “injudicious use.” “In contrast,” the draft states, “FDA considers uses that are associated with the treatment, control or prevention of specific diseases, including administration through feed and water, to be uses that are necessary for assuring the health of food-producing animals.”

FDA outlines “important factors to consider” to determine preventive use:

  • Evidence of effectiveness
  • Evidence that such preventive use is consistent with accepted veterinary practices
  • Evidence that the use is linked to a specific etiological agent
  • Evidence that use is appropriately targeted
  • Evidence that no reasonable intervention alternatives exist.

Antibiotics that are not currently labeled for disease prevention, treatment or control could continue to be used if, after undergoing a second rigorous FDA approval process, one of those label claims is proved. But such a review process typically takes seven to 10 years and can cost antibiotics manufacturers millions of dollars, points out National Pork Producers Council officials.

Another principle of FDA’s guidance is that “the use of medically important antimicrobial drugs in food-producing animals should be limited to those uses that include veterinary oversight or consultation.”

This addresses over-the-counter application of antibiotics and would move usage to a “feed-directive” or prescription basis. FDA sees this as a “phase-in process.”

NPPC, which supports veterinary supervision, is concerned that there are even enough veterinarians available for such oversight, as the shortage of food-animal veterinarians is growing. NPPC points out that producers already work with their veterinarians to develop animal-health plans, including judicious antibiotic use. There’s also the FDA-reviewed Pork Quality Assurance Plus program that educates producers about responsible use.

So, the basic premise of FDA’s proposed guidance is to limit the use of antibiotics deemed “medically important for humans.” Another mission is to inform the public of FDA’s current thinking on the use of medically important antimicrobial drugs in food-producing animals.

“There is concern at FDA regarding antibiotic use in livestock,” Flynn says. “The broader public concern is about antimicrobial resistance — in general terms, that drugs become less effective because bacteria become resistant to them.” He points out that antibiotic resistance arises from all antibiotic uses, including human application.

Flynn says FDA is not looking at this as a move to ban antibiotic use altogether. Rather, it’s to look at how antibiotics are used on farms and ensure that it’s done judiciously. “We believe if we can limit how antibiotics are used it will slow down the process by which resistance emerges,” he adds.

But that’s exactly where the controversy heats up.

Asked if he had documented proof that antibiotic use in livestock had any adverse effects on human health, Flynn says there is sufficient concern to take steps to address antimicrobial drug resistance.

“FDA and others who support this say there’s plenty of science,” says Dave Warner, NPPC communications director. “But what they’re talking about is that there is plenty of science to say antibiotic use (overall) leads to antibiotic resistance. That’s a general fact because bacteria evolve. There is no science that says antibiotic use in livestock leads to antibiotic resistance in humans.” In fact, top scientists with the Centers for Disease Control and Prevention and the National Institutes of Health recently told a U.S. House committee exactly that.

At last month’s House subcommittee hearing, Randall Singer, University of Minnesota epidemiologist, told congressmen “all uses of antibiotics improve animal health, and these improvements can substantially improve human health. The best way to manage antibiotic use in animal agriculture is through sound, rational, science-based policy.” Singer has researched  antibiotic uses and antibiotic resistance for the past 12 years.

Regarding Denmark’s 1998 ban on antibiotic growth promoters and preventives, Singer testified that removing those products “from use in food animals resulted in an increased reliance on therapeutic doses of medically important antibiotics to treat the ill animals.”

Christine Hoang, DVM, with the American Veterinary Medical Association, cautioned against federal bans on the judicious use of antimicrobials in animal agriculture, stating that there can be far-reaching impacts on animal and human health.

“The veterinarian must always consider the individual animal and its welfare; other animals and humans in contact with that animal; and, if it is a food animal, we must ultimately consider the people who consume the end product,” she testified.

AVMA supports measures to mitigate risks to human health associated with use of antimicrobials in agricultural animals and will work with FDA to develop guidelines for such use. But she pointed out that more study needs to be done to determine both effectiveness and risk.

A significant concern is that if products are lost or use becomes problematic, animals won’t be as healthy entering the food chain. “Studies show animals that have been sick during their lifetime have higher incidence of food-borne pathogens than those that haven’t been sick,” Warner notes. At slaughter, those pathogens can move along with the carcass.

“Bottom line, we want all the tools available to keep our animals healthy, because healthy animals produce safe food,” he adds.

Adding even more fuel to the issue is the fact that more than 1,000 medical doctors and other healthcare providers signed requests for Congress to pass legislation reducing non-therapeutic antibiotic use in food animals. The international coalition Health Care Without Harm reports 300 hospitals have signed pledges to purchase only meat raised without antibiotics for their foodservice programs.

So, it’s clear this ongoing debate will only heat up further in the days ahead.