Maryn McKenna: What do we do when antibiotics don’t work any more? (TeD Talk)


Penicillin changed everything. Infections that had previously killed were suddenly quickly curable. Yet as Maryn McKenna shares in this sobering talk, we've squandered the advantages afforded us by that and later antibiotics. Drug-resistant bacteria mean we're entering a post-antibiotic world — and it won't be pretty. There are, however, things we can do ... if we start right now.




Important Points:
Penicillin was distributed in 1943, and widespread penicillin resistance arrived by 1945. Vancomycin arrived in 1972, vancomycin resistance in 1988. Imipenem in 1985, and resistance to in 1998. Daptomycin, one of the most recent drugs, in 2003, and resistance to it just a year later in 2004.
Bacteria develop resistance so quickly that pharmaceutical companies have decided making antibiotics is not in their best interest, so there are infections moving across the world for which, out of the more than 100 antibiotics available on the market, two drugs might work with side effects, or one drug, or none.
In 2000, the Centers for Disease Control and Prevention, the CDC, identified a single case in a hospital in North Carolina of an infection resistant to all but two drugs. Today, that infection, known as KPC, has spread to every state but three, and to South America, Europe and the Middle East. In 2008, doctors in Sweden diagnosed a man from India with a different infection resistant to all but one drug that time. The gene that creates that resistance, known as NDM, has now spread from India into China, Asia, Africa, Europe and Canada, and the United States.
It would be natural to hope that these infections are extraordinary cases, but in fact, in the United States and Europe, 50,000 people a year die of infections which no drugs can help. A project chartered by the British government known as the Review on Antimicrobial Resistance estimates that the worldwide toll right now is 700,000 deaths a year.
If we lost antibiotics, here's what else we'd lose: First, any protection for people with weakened immune systems -- cancer patients, AIDS patients, transplant recipients, premature babies.
Resistance is an inevitable biological process, but we bear the responsibility for accelerating it. We did this by squandering antibiotics with a heedlessness that now seems shocking.
In the United States, 50 percent of the antibiotics given in hospitals are unnecessary. Forty-five percent of the prescriptions written in doctor's offices are for conditions that antibiotics cannot help. And that's just in healthcare. On much of the planet, most meat animals get antibiotics every day of their lives, not to cure illnesses, but to fatten them up and to protect them againstthe factory farm conditions they are raised in.
In the United States, possibly 80 percent of the antibiotics sold every year go to farm animals, not to humans, creating resistant bacteria that move off the farm in water, in dust, in the meat the animals become.
Aquaculture depends on antibiotics too, particularly in Asia, and fruit growing relies on antibiotics to protect apples, pears, citrus, against disease. And because bacteria can pass their DNA to each other like a traveler handing off a suitcase at an airport, once we have encouraged that resistance into existence, there is no knowing where it will spread.

Evolution always wins. Bacteria birth a new generation every 20 minutes. It takes pharmaceutical chemistry 10 years to derive a new drug. Every time we use an antibiotic, we give the bacteria billions of chances to crack the codes of the defenses we've constructed.There has never yet been a drug they could not defeat.
This is asymmetric warfare, but we can change the outcome. We could build systems to harvest data to tell us automatically and specifically how antibiotics are being used. We could build gate keeping into drug order systems so that every prescription gets a second look. We could require agriculture to give up antibiotic use. We could build surveillance systems to tell us where resistance is emerging next.
I know that the scale of antibiotic resistance seems overwhelming, but if you've ever bought a fluorescent light bulb because you were concerned about climate change, or read the label on a box of crackers because you think about the deforestation from palm oil, you already know what it feels like to take a tiny step to address an overwhelming problem.
We could forgo giving an antibiotic if we're not sure it's the right one. We could stop insisting on a prescription for our kid's ear infection before we're sure what caused it. We could ask every restaurant,every supermarket, where their meat comes from. We could promise each other never again to buy chicken or shrimp or fruit raised with routine antibiotic use, and if we did those things, we could slow down the arrival of the post-antibiotic world.
Penicillin began the antibiotic era in 1943. In just 70 years, we walked ourselves up to the edge of disaster. We won't get 70 years to find our way back out again.



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