I was out of the country when CDC (Centers for Disease Control) released their new report on Antibiotic Resistance Threats for 2013,
The majority of the report was on the main cause of antibiotic resistance in humans, which is antibiotic use in humans. Although people love to talk about how many tons of antibiotics are used in food animals, HUMAN use is still the main cause of antibiotic resistance. On that note, my favorite part of the report gives an important lesson and guiding principle for both human AND animal antibiotic use: “SIMPLY USING ANTIBIOTICS CREATES RESISTANCE.” This point is absolutely accurate and compelling (it is found at the bottom of the infographic on page 14, Figure 1 below). For this reason, agriculture and veterinary medicine do not support the misuse, overuse, or excess use of this valuable resource. Therefore, antibiotics for growth promotion are being phased out of livestock production.
However, I and the science of risk assessment, may disagree with CDC about the relative impact that food animal antibiotic use has on human risk. I say may disagree, as they don’t really say specifically how much of the problem is due to agriculture. The infographic I mentioned could be taken to infer equal contribution from agriculture and human uses. I would prefer to see the graphic revised as shown in Figure 2 below. Herein, I show the relatively minor contribution that on-farm antibiotic use to human health risk.
The reasons I am confident the agricultural contribution is low are based on multiple peer-reviewed scientific articles where the risk was quantitatively estimated. (Boy that is a mouth-full, but see the previous blog.) Additionally, FDA has reviewed most currently approved animal antibiotics. If they had found evidence of risk, they would have removed those products from the market, like they did with fluoroquinolones for treatment of poultry disease in 2000.The FDA as well as veterinarians are working to reduce the risk of antimicrobial resistance.
Regardless of who is responsible, I’ll be the first to admit that there is a problem with resistance. But it is not a new problem. Resistance has been a problem since the first teenager disagreed with her parent and since the first antibiotic was used. This is because antibiotic resistance is a natural phenomenon. Resistant bacteria have been found in places untouched by man. To reduce agriculture’s contribution to the problem, veterinarians and farmers use only FDA approved products, are increasing veterinary oversight and are implementing aggressive quality assurance programs.
For further information, see CDC Response Part 2.