Antibiotic resistance a complex issue

Nov 25, 2013

—Recognition of shared responsibilities between human and animal use needed

It’s been said that if someone thinks they understand antibiotic resistance, they don’t properly understand the issue. It’s just plain too complex.

Last week was Antibiotic Awareness Week in the U.S. and other countries. Of course, this meant a lot of attention was directed at the problem of antibiotic resistance. However, both an appeal from an international panel of experts, as well as the speakers of the recent antibiotic-focused convention stressed that the issue is a complicated one.

“Antibiotic resistance has been called the single most complex problem in public health,” said Dr. Nevil Speer, Co-chair of the National Institute for Animal Agriculture’s (NIAA’s) recent symposium, “Bridging the gap between animal health and human health.” Speer is also a professor at Western Kentucky University and Coordinator of the MA Leadership Dynamics Program in the department of agriculture.

While the symposium preceded Antibiotic Awareness Week, the awareness initiative was marked with a lengthy appeal from a group of experts commissioned by The Lancet, a medical journal. The scientists and topic experts who made up the Lancet commission called for global action on the issue of antibiotic resistance.

“The decreasing effectiveness of antibiotics in treating common infections has quickened in recent years,” wrote the commission in its article, “Antibiotic resistance—the need for global solutions.” It described humanity “at the dawn of a post-antibiotic era.”

“In high income countries, continued high rates of antibiotic use in hospitals, the community and agriculture have contributed to selection pressure that has sustained resistant strains, forcing a shift to more expensive and more broad-spectrum antibiotics. In low income and middle income countries, antibiotic use is increasing with rising incomes, high rates of hospitalization and high prevalence of hospital infections.”

Agriculture’s involvement

Though the mention of agricultural use is early on, the commission focused its attentions first on the rise of antibiotic use in humans. Occasional mentions of agriculture surface in sections dealing with human use, but it is not until part four of the appeal (out of eight total, and the last of the “problem” sections) that antibiotic use in animals was addressed. The commission again acknowledged the problem of complexity.

“Use of antibiotics in animals and its potential effect on human health has been a controversy for at least half a century, presently fueled by the crisis of resistance. Predictably, the debate is polarized.

Results of scientific studies have sometimes been conflicting, which is confusing for readers unfamiliar with the context.”

The commission’s appeal included one such example of conflicting scientific claims. At one point the commission claims, “There is little separation of the types of antibiotic used in human beings and animals.” Yet numerous scientific groups speaking on behalf of animal agriculture all but yell themselves hoarse pointing out the opposite.

Dr. Richard Raymond, former Under Secretary of USDA’s Food Safety Inspection Service, is one such individual. He has a long history of being outspoken on the topic of exactly how much human and animal antibiotic use overlaps.

Speaking to Ray Bowman of “Food and Farm” on American’s Web Radio before the NIAA symposium, Raymond responded to questions regarding the balance of responsibility between human and animal use of antibiotics.

“I don’t think there are too many realists who would say human medicine has nothing to play in [antibiotic] resistance. In fact, it is my belief that [human use] has far more than the use of antibiotic in animals because most of the antibiotic used in animals are not even used in human medicine.”

Though exact numbers differ—Raymond says 40 percent, while the infographic at right from the U.S. Farmers and Ranchers Alliance/Food Dialogues says 30 percent, and other sources fall in between—ionophores make up a decent portion of the antibiotics used in food animals. Ionophores are not used in human medicine.

Back in October, following the release of a Pewsponsored report on antibiotic resistance—covered in the Oct. 28 issue of WLJ; “Warring reports on animal ag’s impact”— Raymond pointed out that where human and animal antibiotic use overlaps, the intersection is not equal. He explained that the second and fourth most important categories of antibiotics prescribed for human health—cephalosporins and fluoroquinolones respectively— “comprise 0.3 percent of all antibiotics prescribed for use in animals by veterinarians.”

The path forward

“This year’s antibiotic use and resistance symposium not only shed additional light on this often polarized topic but we identified common ground so a collective path forward that serves the best interests of all parties can be forged,” said Speer of the NIAA symposium.

“The common ground is that it is pretty complex. The pathways go both ways,” said Speer, talking to WLJ. He said that the polarization of the topic, and the tendency of some activists to heap all the blame on animal agriculture—or more frequently, U.S. animal agriculture— is not supported, as well as being unproductive.

He added the shared responsibility in antibiotic stewardship has to be a common ground. “We all have to get off the talking points. It’s not about protecting our little area, it’s an important issue to all of us. This is a global problem.”

Speer’s words of the need to cooperate rather than point fingers was echoed by the Lancet commission.

“In view of the polarized debate, veterinarians and farmers might feel that they are blamed for a problem they perceive is essentially generated by medical doctors. This situation might lead to a defensive attitude and does not cater for productive solutions.

“A way forward would be to acknowledge that human health, animal health, and the environment are all interlinked, and that the responsibility for dealing with the problems of resistance is shared by all stakeholders. Strong local and global partnerships are needed in which policy makers, academia and professionals from all sectors work together to improve present systems. The common goal should be to preserve the effect of antimicrobials for future generations of human beings, but also for animals.”

The NIAA convention, including speakers’ presentations with voiceovers, will be available on the NIAA site by mid-December.

The full text version of the Lancet commission’s appeal, “Antibiotic resistance—the need for global solutions,” can be found online at journals/laninf in the December issue of the journal. The full article is available for free, but requires a free registration to access. — Kerry Halladay, WLJ Editor