The Food and Drug Administration announced Wednesday that it will be restricting the use of cephalosporin – a type of antibiotic – in food animals in order to prevent the growth of antibiotic-resistant strains of human diseases.

The cephalosporin class of drugs is used to treat a variety of serious conditions, including skin infections, urinary tract infections, pneumonia, abdominal infections, bone infections, pelvic inflammatory disease and meningitis. 

Of all drugs prescribed to outpatients, 14 percent are from the cephalosporin class. 

“Newer cephalosporins are used in the hospital setting to treat seriously ill patients with life-threatening disease,” according to FDA.

Mounting scientific evidence has shown that the overuse of cephalosporin in food animals is contributing to the development of drug-resistant strains of these bacteria.

“If cephalosporins are not effective in treating these diseases,” said FDA in a statement Wednesday, “doctors may have to use drugs that are not as effective or that have greater side effects.”

Two foodborne illnesses – Salmonella and Shigella infections – are commonly treated with these drugs. It is via these bacteria that cephalosporin resistance is thought to be transmitted from animals to humans. 

“It is likely that the extralabel use of cephalosporins in certain food-producing animal species is contributing to the emergence of cephalosporin-resistant zoonotic foodborne bacteria,” reads the FDA rule. 

Properties of resistance can then be transmitted from one bacteria to another. 

“What the science is telling us is that these bacteria all communicate and share information with each other and they pass along these resistance genes, and that’s a really troubling thing,” said Laura Rogers of Pew Charitable Trusts, a public policy watchdog. Rogers is project director for the organization’s Campaign on Human Health and Industrial Farming.

And once bacteria develop resistance to one type of cephalosporin, they can become resistant to others.

“Resistance to certain cephalosporins is of particular public health concern in light of the evidence of cross-resistance among drugs in the cephalosporin class,” FDA explains in its rule. 

The agency is not forbidding the use of these drugs in animals outright, but is eliminating “extra-label” or “off-label” use, unapproved uses that may contribute to antibiotic resistance. 

The newly prohibited uses include:

Using cephalosporins at unapproved dose levels, frequencies, durations or routes of administration

Using cephalosporin drugs in cattle, swine, chickens or turkeys that are not approved for use in that species (e.g. ones intended for human or companion animals)

Using cephalosporins for disease prevention

However, cephalosporins will still be permitted for use in the following scenarios:

Cephaprin, an older drug of this class not believed to contribute significantly to antiobiotic resistance, may still be used on livestock.

Veterinarians can still prescribe cephalosporins for limited extra-label use in cattle, swine, chickens and turkeys.

Cephalosporins may still be prescribed for minor species of food-producing animals such as ducks or rabbits.

These exceptions to the prohibition of extra-label uses are new to FDA’s proposed rule on cephalosporins. The agency issued an earlier version of this rule in June of 2008, but withdrew it after it met with criticism because it outlawed uses of the drug that did not lead to antimicrobial resistance.

FDA’s new order, scheduled to go into effect in April, follows a notice published in the Federal Register just before the holidays that indicated the agency was backing away from a 1977 announcement that it had decided not to withdraw penicillin and tetracyclines in animal feed. 

The agency said it was planning to “focus its efforts for now on the potential for voluntary reform and the promotion of the judicious use of antimicrobials in the interest of public health.” 

In November, to the dismay of consumer and sustainable agriculture advocates, the FDA rejected two petitions to ban certain antibiotics from being used in food animal production. It said it was “currently pursuing other alternatives to address the issue of antimicrobial resistance related to the production use of antimicrobials in animal agriculture.”

But in announcing the new order Wednesday, Dr. Michael Taylor, the FDA’s commissioner of foods, said, “We believe this is an imperative step in preserving the effectiveness of this class of important antimicrobials that takes into account the need to protect the health of both humans and animals.”

The Pew Campaign praised FDA’s latest announcement, saying it targets cephalosporin use where it is most abused. 

“I think this is acknowledging that there have been some misuses of the drug,” Gale Hansen, senior officer of Pew’s Campaign on Human Health and Industrial Farming, told Food Safety News. 

Each year, 9 billion broiler eggs are processed in America, and the majority of them are injected with cephalosporins. The drug is also widely administered to cattle for disease prevention. These pratices will be banned under the new rule.

However, other consumer advocates pointed out that cephalosporins make up only a small percent of all antibiotics administered to livestock for purposes such as boosting growth.

In fact, cephalosporins account for .2 percent of antibiotics administered to animals domestically each year. 

Consumer groups criticized FDA for not including in its restriction other drugs that have also been shown to promote antimicrobial resistance.

“It’s high time that the FDA wakes up to the dangers of non-therapeutic uses that all antibiotics pose to our health and the safety of our food supply,” said Andrew Kimbrell, executive director of the Center for Food Safety, in a statement Wednesday.

But despite cephalosporin’s small share of the animal antibiotic pie, Rogers points out that the drug has large implications for human health. 

“Cephalosporins may not be used as extensively as some other drugs, but these drugs are critically important to human health, and so we need to protect them and use them as judiciously as possible,” she says. 

Other consumer advocates agree that these restrictions are indeed necessary, but say they have been too long in coming.

“The order prohibiting certain uses of cephalosporin in many food-producing animals is clearly warranted, though it may be too little, and it is definitely too late,” said Caroline Smith DeWaal, Food Safety Director of the Center for Science in the Public Interest (CSPI) in a stateme
nt Wednesday.

U.S. Rep. Louise Slaughter, D-NY, a microbiologist who has sponsored bills aimed at preserving antibiotics’ effectiveness for treating human disease, was even more critical of the FDA’s new order.

In a statement she said the rule addresses “just the tip of the iceberg” and noted that the announcement comes three years after the FDA determined that extra-label use in food animal production posed a public health threat.

“This is a modest first step by FDA,” she wrote. “We don’t have time for the FDA to ploddingly take half-measures. We are staring at a massive public health threat in the rise of antibiotic-resistant superbugs. We need to start acting with the swiftness and decisiveness this problem deserves.”

CSPI pointed out that at least five foodborne outbreaks since 2001 have been linked to cephalosporin-resistant Salmonella. These outbreaks resulted in more than 200 illnesses and one death.

FDA noted in its question and answer document on the rule that restrictions have already been placed on 14 other drugs thought to contribute to antimicrobial resistance, and that the agency continues to promote the “judicious use” of animal antibiotics, as evidenced by its Draft Guidelines on animal antibiotic use issued in 2010. 

“This action is among a number of ongoing FDA activities and initiatives intended to address concerns about the use of antimicrobial drugs in animal agriculture,” says the agency’s Q&A page.

A 60-day comment period on the new rule will run from Jan. 6 to March 6. The FDA said it will take those comments into consideration before the new order goes into effect April 5.