At the Lunch Colloquium on Tuesday, October 8, Maryn McKenna, Senior Fellow at Emory College's Center for the Study of Human Health, gave a fascinating yet sobering talk on antibiotics in our food system. As a journalist focusing on public health, she had an obsession that began with her research into the rise of drug resistant bacteria, due in part to the wide use of antibiotics in our meat production. The use of antibiotics in meat production began with chickens; they served as the model for all meat production. Antibiotics were used to make the animals grow quicker and to protect them from diseases that arise in crowded barns. She has discussed that development and its consequences (and attempts to deal with them) in her prize-winning book Big Chicken: The Incredible Story of How Antibiotics Created Modern Agriculture and Changed the Way the World Eats.

McKenna posited that we have arrived at this serious state due to four factors:

• Trusting technology too much;
•  Failing to ask questions of science;
• Assuming there is only one path to progress;
• Taking things for granted.

We are losing the power of antibiotics because by misusing and overusing them we have allowed the bacterial world to adapt to them.

Penicillin was the first antibiotic, used widely in WWII. After the war, the food supply was strained and the meat industry was over-extended. To reduce costs, farmers used cheaper feed, which in turn required the use of supplements to provide the needed nutrition. And those supplements began to include small doses of penicillin (and eventually other antibiotics), not to cure infections, as when they're prescribed for people, but to prevent disease and promote growth.

What was most depressing about McKenna's talk was that Alexander Fleming, the scientist who discovered penicillin, warned in his 1945 Nobel Prize speech that using doses of antibiotics that were too small to cure an infection (much less when there was no infection) would allow bacteria to learn to resist the drugs. We didn't listen.

In the U.K. children were developing penicillin allergies, cheese-makers could not make cheese because there was too much penicillin in the milk, there was an outbreak of Salmonella, and 13 children died from a drug-resistant food-borne strain of E. coli. A UK commission in 1969 issued the Swann report, which made the first recommendations for farm antibiotic control.

Slowly the US took note of the UK findings. In the 1970s, Dr. Levy at Tufts University set up an experimental farm. His work proved two things:

• Routine antibiotic doses did affect the gut bacteria of the animals that received them, turning those bacteria toward resistance or increasing the proportion of bacteria that are resistant. When animals were slaughtered, the contents of their guts contaminated the meat they became and traveled on that meat into kitchens and onto plates.
• There was also a risk while farm animals were alive, because their manure would flow into a farm's environment, and the resistant bacteria contained in the manure would begin to move through the world in a manner that was unpredictable.

The FDA tried to take away licenses for growth-promoter uses of antibiotics, but the agricultural lobby prevented this action.

The Scandinavian countries outlawed most farm antibiotic use and the European Union created a total ban on growth promoters in 2006. Sadly, the United States continued to allow growth promoters and waited to see whether resistant bacteria would emerge. They did.  And there have been numerous epidemics our usual antibiotics couldn't deal with well. 

McKenna hypothesized that we didn't take seriously the threat of antibiotic resistance because we assumed that, however bad resistance might get, there would always be another newer antibiotic to cure it. However, there has been no new antibiotic compound developed in over 30 years; it's just not profitable for Big Pharma.

Predictions are that if we do not change our antibiotic use - in medicine and in protein production - there will be 10M deaths by the year 2050.

Thankfully, McKenna ended her presentation with some positive news.  For example, although there is widespread use of antibiotics in fish as well as meat, consumer pressure is forcing some corporations to change their practices in purchasing fish. Costco has cancelled a salmon contract with Chile and is now sourcing from Norway. The cooler waters in the north require less use of antibiotics.

As for chicken, in 2014, Perdue Farms, the fourth-largest chicken producer in the United States, announced that it was taking its chicken antibiotic-free. Other chicken producers quickly followed suit.

In 2016, the central Chinese government banned the antibiotic Colistin from farm use, so we're not getting it from our imports from China anymore.

In January 2017, in one of its final acts, the Obama Administration engineered the removal of growth promoters from the US market, breaking the four-decades stalemate that followed that abortive attempt at regulation so many years ago.

However, these developments are not enough. The US and many countries still allow the preventive use of antibiotics in animals that are not sick. The movement of resistant bacteria across the world shows us that we can no longer pretend one country or ecosystem is separate from another. Foods are flown across the world. Pathogens cross borders on birds, in the wind, in the oceans, and in our bodies. The fight to eliminate the use of antibiotics in our food production continues.

There was a lively Q&A. But time ran out. So in case your Qs weren't answered, you are encouraged to read McKenna's books (like Big Chicken) and articles (published in venues like The York Times Magazine, The New Republic, Smithsonian, The Atlantic, Newsweek, Scientific American, Nature, and The Guardian, among others).

--Lee Pasackow