April 2015 Issue

Antibiotics in Meat
By David Yeager
Today's Dietitian
Vol. 17 No. 4 P. 36

Dietitians and meat industry professionals discuss this controversial practice and what can be done to possibly curtail it.

Since the 1940s, antibiotics have saved numerous lives and greatly reduced the suffering associated with a wide range of diseases. In the past few decades, however, the number of antibiotic-resistant bacteria has increased dramatically, giving rise to a significant public health threat. Each year, in the United States alone, at least 2 million people are infected by antibiotic-resistant bacteria and at least 23,000 people die from those infections.1 Worldwide, diseases that were once well-controlled by antibiotic use, such as malaria, tuberculosis, cholera, diarrhea, and pneumonia, have become resistant to standard treatments.2 In some cases, these diseases are resistant to as many as 10 different drugs.2 In addition, bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) account for a high percentage of hospital-acquired infections.3

There are many reasons these "superbugs" have been able to proliferate. One is that, although new antibiotic medications may be profitable, people often take them for only one to two weeks at a time. Therefore, the drugs don't generate the same returns as those used to treat chronic diseases that people may take for decades. In turn, pharmaceutical companies tend to spend less money researching and developing antibiotics than they do for drugs used to treat chronic diseases.
Another reason is evolution: The bacteria that have survived naturally are more resistant to antibiotics than most of their ancestors. Human actions, though, significantly have hastened the evolutionary progress of these microbes. Not taking antibiotic medication as prescribed, such as not finishing a course of antibiotics or taking substandard doses, is a significant culprit in the rise of antibiotic resistance.4 Other notable causes are the incorrect prescribing of antibiotics for illnesses that don't warrant them, as well as poor infection prevention and control.4 A lack of governmental oversight also has been problematic.4

A significant cause that's of particular concern to dietitians and their clients, however, is the routine use of medically important antibiotics developed for humans in the meat industry. In addition to treating sick animals, antibiotics have been used in meat production to promote growth in otherwise-healthy animals by giving them subtherapeutic doses.5 This has contributed to the growth of antibiotic-resistant strains of Salmonella, Campylobacter, and E. coli, which have caused difficult-to-treat human infections.5 Classes of drugs approved for animal use that the FDA classifies as critically important to human health include third-generation cephalosporins, fluoroquinolones, macrolides, and the combination of trimethoprim and sulfamethoxazole.6
Part of the problem has been that, although veterinary oversight is required to administer antibiotics to sick livestock, antibiotics have been widely available without a prescription as feed supplements. In 2012 and 2013, the FDA released Guidance for Industry documents addressing the use of antimicrobial agents in animal feed and the need for veterinary supervision, but the FDA's program is voluntary.7,8

David Wallinga, MD, director of Healthy Food Action, a national network of health professionals weighing in on food policy, says antibiotic use in livestock should be reduced significantly. "Based on how antibiotics have been used in meat production in the past, I think it's likely that as much as 70% or more of the antibiotics in livestock production are overused," Wallinga says. While domestic sales and distribution of medically important antimicrobial drugs for humans that were approved for growth promotion purposes in food-producing animals declined from 72% to 68% between 2009 and 2012, this statistic doesn't represent sales attributable to products used solely for growth promotion, because many drugs are approved for both growth promotion and treatment of sick animals.9 In addition, varying definitions of "therapeutic" vs "nontherapeutic," or "growth promoting" make it difficult to determine the reasons for use of several types of antibiotics.10

The FDA has been working on a new directive that would prevent the sale of antibiotics for growth promotion and bring all antibiotic use under veterinary supervision, but Wallinga says he's concerned that the directive won't make enough of an impact. In particular, he's concerned that enforcement of the directive will be left to the states and that there won't be adequate implementation. To truly address the use of antibiotics in livestock production, Wallinga says a culture change is needed.

Getting Cultured
Culture changes, however, rarely are easily established. They can be accomplished, however, when there's enough public determination. For example, a significant culture change in livestock production has occurred in the Netherlands. Although small in land mass, the Netherlands is Europe's leading meat exporter.11 A decade ago, the Netherlands had low rates of antibiotic resistance due to strict policies for infection prevention in hospitals and agreements regarding when to use the most powerful antimicrobial drugs.11 However, farms in the Netherlands were among the highest users of antibiotics in Europe.11 Due to strains of MRSA and other drug-resistant infections that were traced to Dutch farms, the Netherlands' government appealed to powerful private agriculture organizations for help.11

With industry buy-in, the Dutch agriculture minister implemented a policy that stopped preventive antibiotic dosing, required veterinary inspections before any animal received antibiotics, and set targets for curbing the use of antibiotics: 20% in one year and 50% in three years.11 Antibiotic sales to livestock farms dropped 56% between 2007 and 2012.11 The most impressive aspect of this change is that it didn't harm either the efficiency or sales of Dutch livestock operations.11 Although similar changes in the United States potentially could be more difficult to implement, there are signs that attitudes among livestock producers are shifting.
Perdue Farms, one of the largest chicken producers in the United States, says 95% of its chickens never receive any human antibiotics, and the remainder receive them only when prescribed by a veterinarian.12 This change in practice is more restrictive than the FDA's Guidance for Industry recommendations that were released in December 2013.8 Perdue and Tyson Foods, another large poultry producer, also have stopped injecting antibiotics into eggs that are about to hatch, which has been a common practice in the industry.13,14

"Farmers are constantly concerned about what consumers want and need, and they are very, very good at adjusting and changing to meet those needs and those demands, while keeping their herds healthy and doing what's in the best interests of those animals," says Erin Brenneman, a hog farmer in southeast Iowa.
Brenneman has worked as a hog farmer for 10 years and, during that time, she says farmers have become more judicious in how they administer antibiotics.
Brenneman and her family run a farm that processes 500,000 head of swine each year. Her husband works in the nurseries and finishing farm areas of the operation, while her area of expertise is in the sow farm, an operation that encompasses three sites and holds around 6,000 sows and piglets at any given time.

Brenneman says the farm adheres to strict policies on the medical treatment of animals, such as how much of an antibiotic is given, the reason, the route of administration, and the withdrawal period. The treatments are recorded, and the medical card information stays with the sow. Brenneman says her farm doesn't add antibiotics to feed for growth purposes, but does add antibiotics prophylactically at certain cycles of the pigs' lives when they're more susceptible to disease, such as when they're weaned. She says her farm's policies on antibiotic use are in line with most farms in the industry.

The issue of prophylactic antibiotic use in livestock is a thorny one. Some people are opposed to it because of concerns about the growth of antibiotic-resistant microbes. Jacob Geis, DVM, a rancher in Nebraska with around 65 head of cattle, says there are times when the use of prophylactic antibiotics can increase the efficacy of the medicine, such as at the first sign of illness. He says administering antibiotics immediately can help reduce illness and prevent it from spreading throughout the herd. Although it can be difficult to determine when cattle are sick—because of their herd instinct, Geis says they try not to let on when they're not feeling well—Geis performs a physical exam before treating the animal with antibiotics.

"If we're using antibiotics, we want to make sure that we're using them appropriately," Geis says. "If we're going to continue to use antibiotics indefinitely, into the future, we want to make sure that they stay effective. I'm talking about treating animals but, obviously, the same applies to the human side. So, it's really important for me, as a veterinarian but also as a rancher, that when I'm treating something, I'm treating it for a good reason so that the antibiotics remain effective down the road."

Geis finds it encouraging that the White House has proposed additional spending for antibiotic research and development.15 He says the cattle industry has been working with the FDA to phase out the use of antibiotics for growth promotion and expects that practice to be eliminated within a couple of years. He adds that antibiotics administered to farm animals don't leave a residue in the meat that people put on their tables.

What to Eat
Stacia Clinton, RD, LDN, a regional director of the Healthy Food in Health Care program for Health Care Without Harm, a nonprofit organization dedicated to local and sustainable institutional purchasing and program development, says that because antibiotic residues in meat are closely regulated, they're not an issue of concern. What the public should be concerned about, she says, is the use of antibiotics in animal feed. Antibiotics from animal feed and waste can be released into the environment and leach into soil or drinking water.10 In addition, farm workers who are exposed to antibiotic-resistant bacteria potentially can carry those microbes to the general population.10

Clinton believes antibiotic use in the meat industry needs to be more clearly defined and more closely monitored. She supports H.R. 1150, known as the Preservation of Antibiotics for Medical Treatment Act of 2013, which would strictly limit the use of antimicrobial drugs in animals that are important to human health.16 That bill was introduced on March 14, 2013, was referred to the House Subcommittee on Health on March 15, 2013, and has yet to be reviewed by the House of Representatives.16
Because most antibiotic regulation is voluntary and food labels can be misleading or confusing, Clinton says dietitians need to educate the public about how antibiotic use in meat production can affect them. She sees this as an important step in developing sustainable food policies. She says dietitians can use their platform to advocate for shifts in food purchasing practices by institutions to favor farm operations that limit antibiotic use, speak out on policy matters, and highlight the nutrition principles of a well-balanced diet.

"Dietitians can guide individuals to make food choices that will keep them more in line with dietary guidelines to reduce overall meat consumption," Clinton says. "One of the primary programs I promote that does this is called the Balanced Menus Initiative,17 which guides individuals to reduce their overall meat purchases and then shift any cost savings, as a result of that, toward the purchase of sometimes more expensive, sustainably produced meat. That's sort of a gradual transition to put your purchasing dollars where your values are."

Moreover, there are government resources dedicated to addressing the issue of antibiotic resistance as it relates to farm animals. The FDA's National Antimicrobial Resistance Monitoring System tracks trends, disseminates information, and conducts research on antimicrobial resistance.18 The USDA's Agricultural Marketing Service also has a program called Never Ever 3, which allows livestock and meat producers to submit marketing programs to the USDA's Livestock and Seed Program for verification and monitoring.19 The program allows producers to market their products as being free of antibiotics, growth promotants, and animal by-products.19

Ashley Colpaart, MS, RDN, the past chair of the Hunger and Environmental Nutrition Dietetic Practice Group of the Academy of Nutrition and Dietetics, says many larger and smaller meat production operations have gotten on board with limiting the use of antibiotics. She has heard from and seen producers who are looking into the use of probiotics for their animals to produce healthy gut flora and increase disease resistance. What's necessary, Colpaart says, is to balance the needs of meat producers with public health requirements.

The larger issue, Colpaart adds, is that society needs to continue to work toward sustainable food systems. She says dietitians can help guide this conversation by educating the public about how agricultural systems work. The development of sustainable food systems will require strategic thinking but, ultimately, she says consumers will need to support new ways of producing food for those systems to become viable.

"Supporting those systems is important so that those growers know that they're not going to lose market share by changing their practices, even if their cost of production goes up a little in the short term," Colpaart says. "People should be encouraged to support the new production practices with their dollars."

— David Yeager is a freelance writer and editor in southeastern Pennsylvania.

References
1. Antibiotic/antimicrobial resistance. Centers for Disease Control and Prevention website. http://www.cdc.gov/drugresistance. Updated March 4, 2014. Accessed February 23, 2015.

2. Antibiotic resistance. World Health Organization website. http://www.who.int/whr/1996/media_centre/press_release/en/index4.html. Accessed February 23, 2015.

3. Antimicrobial resistance. World Health Organization website. http://www.who.int/mediacentre/factsheets/fs194/en. Updated April 2014. Accessed February 23, 2015.

4. What is antimicrobial resistance? World Health Organization website. http://www.who.int/features/qa/75/en. Updated April 2014. Accessed February 23, 2015. Updated April 2014.

5. World Health Organization. Reduce use of antimicrobials in food-producing animals. http://www.who.int/world-health-day/2011/presskit/whd2011_fs4d_subanimal.pdf. Published 2011. Accessed February 23, 2015.

6. US Department of Health and Human Services, Food and Drug Administration, Center for Veterinary Medicine. Guidance for Industry #152: Evaluating the Safety of Antimicrobial New Animal Drugs with Regard to Their Microbiological Effects on Bacteria of Human Health Concern. Rockville, MD: Center for Veterinary Medicine; October 23, 2003.

7. US Department of Health and Human Services, Food and Drug Administration, Center for Veterinary Medicine. Guidance for Industry #209: The Judicious Use of Medically Important Antimicrobial Drugs in Food-Producing Animals. Rockville, MD: Center for Veterinary Medicine; April 13, 2012.

8. US Department of Health and Human Services, Food and Drug Administration, Center for Veterinary Medicine. Guidance for Industry #213: New Animal Drugs and New Animal Drug Combination Products Administered in or on Medicated Feed or Drinking Water of Food-Producing Animals: Recommendations for Drug Sponsors for Voluntarily Aligning Product Use Conditions with GFI#209. Rockville, MD: Center for Veterinary Medicine; December 2013.

9. US Food and Drug Administration, Department of Health and Human Services. 2012 summary report on antimicrobials sold or distributed for use in food-producing animals. http://www.fda.gov/downloads/ForIndustry/UserFees/AnimalDrugUserFeeActADUFA/
UCM416983.pdf. Published September 2014. Accessed February 23, 2015.

10. Pew Commission on Industrial Farm Animal Production. Putting meat on the table: industrial farm production in America. http://www.ncifap.org/_images/PCIFAPFin.pdf. Accessed February 23, 2015.

11. McKenna M. The abstinence method. Modern Farmer website. http://modernfarmer.com/2014/06/abstinence-method. Published June 17, 2014. Accessed February 23, 2015.

12. Antibiotics Position Statement. Perdue Farms Inc website. http://www.perduefarms.com/News_Room/Statements_and_Comments/details.asp
?id=545&title=Antibiotics%20Position%20Statement. Accessed February 23, 2015.

13. Charles D. Perdue says its hatching chicks are off antibiotics. NPR website. http://www.npr.org/blogs/thesalt/2014/09/03/345315380/ perdue-says-its-hatching-chicks-
are-off-antibiotics. Published September 3, 2014. Accessed February 23, 2015.

14. Antibiotic use. Tyson Foods, Inc website. http://www.tysonfoods.com/Media/
Position-Statements/Antibiotic-Use.aspx. Accessed February 23, 2015.

15. FACT SHEET: President's 2016 budget proposes historic investment to combat antibiotic-resistant bacteria to protect public health. The White House website. http://www.whitehouse.gov/the-press-office/2015/01/27/fact-sheet-president-s-2016-
budget-proposes-historic-investment-combat-a. Published January 27, 2015. Accessed February 23, 2015.

16. Preservation of Antibiotics for Medical Treatment Act of 2013, HR 1150, 113th Cong (2013).

17. Balanced menus initiative. Health Care Without Harm website. https://noharm-uscanada.org/issues/us-canada/balanced-menus-initiative. Accessed February 23, 2015.

18. National antimicrobial resistance monitoring system. US Food and Drug Administration website. http://www.fda.gov/AnimalVeterinary/SafetyHealth/AntimicrobialResistance/
NationalAntimicrobialResistanceMonitoringSystem. Updated August 11, 2014. Accessed February 23, 2015.

19. US Department of Agriculture. Never Ever 3 (NE3). http://www.ams.usda.gov/AMSv1.0/getfile?dDocName=STELPRDC5066028. Published April 6, 2009. Accessed February 23, 2015.