The "Skinny" on the Emergence of Antibiotic Resistant Strains of Bacteria

For many years, I taught medical students that the emergence of antibiotic resistant strains of bacteria primarily resulted from the overuse and misuse of antibiotics by physicians. While this seemed to make sense, I started chatting in the late 1990s with Steve Projan— a well known and highly respect maven on bacterial antibiotic resistance—who told me that the physician story was an urban legend and that the main reason for the emergence of antibiotic resistance was directly related to the use of antibiotics as growth enhancers in livestock feed. Not surprisingly, shortly after my conversations with Dr. Projan, papers began appearing in the literature that corroborated the claims.

Despite a growing body of convincing scientific evidence, the Bush administration did nothing to regulate or reduce the use of antibiotics in live stocks feeds in the US for almost a decade. Last year it is estimated that 35 million pounds of antibiotics were used in the US. Interestingly, 70% were used in cows, chickens and pigs. It is important to point out that the US isn’t the only culprit; recent estimates suggest that 50% of the global antibiotic supply is used by the livestock industry. Recognizing a growing problem, the European Union and other developed countries (not the US) have adopted strong limits on the use of antibiotics for livestock purposes.

Thankfully, the pressure against the use of antibiotics in agriculture and livestock production is rising. The World Health Organization concluded this year that surging antibiotic resistance is one of the leading threats to human health, and the White House last month said the problem is "urgent." Also this year, the three federal agencies tasked with protecting public health — the Food and Drug Administration (FDA), CDC and U.S. Department of Agriculture — declared drug-resistant diseases stemming from antibiotic use in animals a "serious emerging concern." And, this past summer, FDA deputy commissioner Dr. Joshua Sharfstein told Congress that farmers need to stop feeding antibiotics to healthy farm animals.

Pharmaceutical companies and agricultural lobbyists argue that antibiotics keep animals healthy and meat costs low, and have successfully help to defeat a series of proposed limits on their use. To that end, in 2009, drug makers spent $135 million and agribusiness companies another $70 million, lobbying against new limits on the use of antibiotics as livestock growth enhancers. FDA official say that without new laws the agency’s options are fairly limited. Ironically, the agency approved antibiotic use in animals in 1951, before concerns about drug resistance were recognized. And, the only way to withdraw that approval is through a drug-by-drug process that can take years of study, review and comment.

Previous attempts by FDA to limit antibiotic usage have consistently met with limited success. For example, in 1977 the agency proposed a ban on penicillin and tetracycline in animal feed, but it was defeated after criticism from interest groups. In 2000 FDA ordered the antibiotic Baytril (used in the poultry industry) off the market. Five years later, after a series of failed judicial appeals, poultry farmers finally stopped using the drug as a growth enhancer. Finally, in 2008 the FDA issued its second limit on an antibiotic used in cows, pigs and chickens, citing "the importance of cephalosporin drugs for treating disease in humans." But the Bush Administration — in an FDA note in the federal register — reversed that decision five days before it was going to take effect after receiving several hundred letters from drug companies and farm animal trade groups.

Luckily, we now have a President who believes in regulation of big business to protect the health and welfare of Americans and is smart enough to make the scientific connections between emerging antibiotic resistance in animals and human. Maybe some real change will be coming soon....one can only hope!!!!!!!!!!

Hat tip to Ed at the Pharmalot Blog

Until next time...

Good Luck and Good Job Hunting!!!!!!!!!