Antibiotic resistance must be approached using an interdisciplinary strategy based upon collaboration and communication across the fields of human, animal, and ecological health, said Laura Kahn, a co-founder of an multidisciplinary medicine initiative.
Kahn’s “One Health Initiative” shows how best to forge effective policies to regulate the use of antibiotics across disciplines including human and veterinary medicine, said Kahn in an address on 13 September at AAAS headquarters as part of the AAAS Colloquium Series – public lectures that explore timely topics in science and society.
“Since we live in a microbial world, we need to figure out a better strategy than simply relying solely on antibiotics as a form of therapy,” said Kahn, who is a physician and a research scholar at Princeton. “In the long run, our over-dependence on antibiotics is ultimately a failed strategy. I’m not suggesting we stop using them, but relying solely on them is problematic.”
The challenges the medical, scientific, and policy community face in devising ways to address antibiotic resistance are on a global scale, Kahn said. There is no single protocol for identifying or classifying antibiotic resistance, for example, and some nations stringently regulate the use of antibiotics, while others do not regulate them at all, Kahn added.
Kahn traced the history of antibiotics in arguing that alternative approaches are needed to combat bacterial infections.
After penicillin was discovered in 1928, antibiotics were prescribed to treat serious bacterial infections. They were largely effective and lead to significant health improvements. By the 1950s, however, penicillin resistance took hold, and it was not until new antibiotics were introduced that treatment improved. Yet, the cycle repeated itself — the use of a new antibiotic inevitably ushered in the emergence of antibiotic resistance to it.
Research is needed to find new approaches to enhance animal growth for meat and poultry production without depending on antibiotics, said Dr. Kahn at AAAS' Colloquium Series. | Adobe Stock
Among the culprits, Kahn said, was the routine use of antibiotics to promote animal growth for meat and poultry production. The practice has led microbes from farm animals to develop antibiotic resistance, which can be passed on to soil microbes through the application of manure in the environment such as agricultural fields. Many of our antibiotics come from soil microbes, and by exposing them to massive amounts of antibiotic residues and resistant bacteria we are increasing the presence of antibiotic resistant genes across the globe in ways that we do not understand. Wildlife, such as migrating birds, are spreading resistant microbes around the world.
The Food and Drug Administration issued voluntary regulations in 2013 in an attempt to curb the nontherapeutic use of antibiotics on cows, pigs, and chickens to stimulate growth. The regulation, which was phased in over three years, requires drug makers to specify on labels that antibiotics cannot be used to promote animal growth, and required veterinarians to supervise the use of antibiotics.
William T. Flynn, deputy director for science policy at FDA’s Center for Veterinary Medicine, said that while FDA’s recommendation that drug makers change labels to eliminate the use of antibiotics to promote animal growth was voluntary, drug makers have agreed to the recommendations and the changes are targeted to go into effect by 1 January 2017.
It remains to be seen what effect the regulation might have on antimicrobial resistance, if any, Kahn noted.
Kahn said medical specialists should leverage vaccines and bacteriophages, a specialized virus that attacks certain strains of bacteria, in efforts to slow antibiotic resistance.
Scientists also should shift their focus from tracking resistant genes to conducting surveillance of entire microbial genomes in order to find the sources of microbial resistance, rather than simply identifying where the resistant microbes are spreading. Some genomic data suggest, for example, that companion animals such as dogs can be a source of antimicrobial resistance, Kahn said.
“Companion animals have been the invisible animals for a long time and I think that needs to stop,” said Kahn. “These animals share our food, sleep in our beds, and live in our homes. The opportunity for microbial transmission is great and they receive a lot of antibiotics, of which there is absolutely no surveillance whatsoever or political concern at all.”
The Centers for Disease Control and Prevention estimates that more than two million people in the United States contract infections that antibiotics prove ineffective in treating, leading to 23,000 deaths each year. The illnesses and deaths cost anywhere between $20 billion to $35 billion each year.
Kahn suggested that better and more advanced training and rapid diagnostic tests to enable doctors and medical practitioners to improve their diagnostic capabilities could reduce unnecessary prescriptions for antibiotics when someone is suffering from viral infections – illnesses antibiotics cannot treat.
“Right now our diagnostic capabilities are not good enough to be able to look at somebody who is feeling sick and identify exactly what is causing their illness. We can’t tell if it’s a virus or bacteria, so what we do is give them an antibiotic and hope for the best,” said Kahn.
[Associated image: greenvector/Adobe Stock]