Why Bacteria Are More Threatening Than Ever

The stories are harrowing: people with simple cuts who get exposed to bacteria can end up with life-threatening, and sometimes even life-ending, infections. Antibiotics were supposed to prevent these infections and deaths. But in the U.S., about two million people become infected with bacteria that can’t be treated by antibiotics, and at least 23,000 people die from those infections every year.

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The bacteria behind these infections, once common. have mutated to become resistant to the dozens of antibiotics developed to wage war against them. (See exactly how that happens in the video above.) That’s a problem of our own making. Public health experts say that the superbugs are the result of years of overusing and misusing antibiotics, either by dispensing them in too-high doses or using them against minor infections or inappropriate conditions like the flu, which doesn’t respond to antibiotics. Antibiotics are also overused in farming—not just to keep infections at bay, but also as a way to encourage animals like chickens, pigs and cattle to grow larger and produce more meat. With so many antibiotics circulating in people and in animals, bacteria mutate to find ever more clever ways of becoming resistant to the drugs.

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The only way to get ahead of antibiotic-resistant superbugs is to outsmart them. In recent years, doctors have been cutting back on prescribing the drugs, and some hospitals require registries for antibiotics so they can keep track of how much are being used. Educational programs have sprung up designed to teach people about when antibiotics are appropriate, and when they aren’t. In order to fend off superbugs, we have to be as persistent as they are.

Write to Lon Tweeten at lon.tweeten@time.com.