At times within our blog, we’ll be asking industry experts to share their opinions on a variety of issues. While we understand that some of these issues may be controversial and some readers may be sensitive to them, we think these issues present real challenges in the modern food chain and are important to discuss. We look forward to receiving feedback from our readers about these posts…do you agree, disagree, or have additional comments to contribute? –Examining Food Editorial Staff Antibiotic Resistance – Real Hazard or Just Hype? Contributed by The Acheson Group (TAG)
Established in 2013 as an independent venture of Leavitt Partners Global Food Safety Solutions, The Acheson Group, LLC (TAG), led by Dr. David Acheson, is a strategic consulting firm for food and beverage companies and those providing technical support to the food industry.
Antibiotic resistance in bacteria is a very real public health issue and discussions around causes and potential actions have been ongoing for decades. Reports upon reports have warned of impending doom, castigating the use of antibiotics as growth promoters in animals while extolling the virtues of antibiotics for treating sick animals…and everything in between.
From a regulatory standpoint in the U.S., antibiotic use in animals is regulated by FDA’s Center for Veterinary Medicine (CVM). Over the past 10 years, CVM has tackled this issue in various ways, like requiring manufacturers of new veterinary drugs to evaluate the occurrence of antibiotic resistance. They have also suggested judicious use of antibiotics, and have tried to develop an overarching strategy to deal with this complex and politically charged issue. CVM has published written guidance on this issue.1
The most recent move by FDA occurred in early December 2013, when CVM released guidance requesting that industry voluntarily move away from antibiotic use for growth promotion. FDA has also asked the industry to let the Agency know of their intent.1 As expected, the guidance document met mixed reviews. Many within the animal health industry applauded FDA for its actions, and some public interest groups were thankful that FDA finally took action. But others, including many consumer groups, questioned how meaningful the guidance can be since it is voluntary, not mandatory.
So what does the science say? Is antibiotic resistance really an issue? Is misuse within animal agriculture to blame? Is there still time to turn this ship around?
First, there is the issue of whether antibiotic resistant pathogens are more likely to cause foodborne illness than pathogens that are not resistant. In this case, it likely depends on the specific bug. Ongoing research suggests virulence and antibiotic resistance can be linked in some strains but not in others. So, in some cases, antibiotic resistant pathogens may be more likely to cause illness within the healthy population (individuals with comprised immune systems, the elderly, and infants may be more susceptible to all types of pathogens—antibiotic resistant or not).
The bigger problem lies in what happens if you do get sick and need to be treated with antibiotics, which in the case of foodborne illness is the exception not the norm. There are some foodborne pathogens like E. coli O157:H7 that aren’t treated with antibiotics because antibiotics in that instance can make things worse, so resistance becomes a moot point. But if you are infected with a pathogen and need treatment with antibiotics, and the infecting pathogen is resistant to those antibiotics, you could be in trouble. So, yes, antibiotic resistance really is an issue in the treatment of illness in both humans and animals.
Now we get to the blame game. The finger is often pointed at the animal agriculture industry, who points the finger back at physicians who prescribe antibiotics to treat a child’s runny nose (likely caused by a viral infection, not bacterial) if mom asks. The truth is, the use of antibiotics—from any source—cause the environmental pressure that selects for those mutant bacteria that happen to be resistant.
But who uses more antibiotics, animals or humans? And is it about the volume of antibiotics or the type of antibiotics that are used? There are few, if any, well-designed studies that can provide a meaningful comparison. The fact that we don’t have a great sense of antibiotic use may seem shocking since this question mark has existed for years. The challenge is that different studies define “antibiotics” and “antimicrobials” differently, making comparisons between studies almost impossible.
Regardless of who’s to blame, if antibiotic use is curbed, can we reverse the trend toward resistance? From the microbiological perspective, yes, at least in theory and to some extent. But it’s important to realize that antibiotics serve a real public health purpose in treating disease in both humans and animals, so the microbial environment will continue to be exposed to antibiotics for good reason.
In short, this is a complicated issue. But the key here is judicious use. Use antibiotics when needed (both for humans and animals), not when they are not. And if discontinuing some applications of antibiotics means that we lose the effect of growth promotion, maybe we can address this through other means such as non-antimicrobial additives in animal feed or genetic modification… but we’ll wait for the next blog post to tackle that issue! (Keep an eye on the blog in coming months when the TAG team discusses GMO’s in the food chain.)
Reference 1 FDA, 2013. Guidance for Industry #213 [pdf]. FDA. Available at: http://www.fda.gov/downloads/AnimalVeterinary/GuidanceComplianceEnforcement/GuidanceforIndustry/UCM299624.pdf [Accessed 01.201.2014].