One of the mysteries of COVID-19 is why it kills some patients while sparing others with similar health profiles.

The answer to this will not prove singular, of course. But research published in the prestigious medical journal The Lancet found that 50% of hospitalized patients who died of COVID-19 also had secondary bacterial infections. Some patients contracted these fatal infections from the very intensive care unit (ICU) ventilators that were intended to save them.

By contrast, just 1% of hospitalized COVID-19 survivors suffered from secondary infections.

Too often, the secondary bacterial infections that exploit those who are already ill are resistant to our existing arsenal of antibiotics. These “superbugs” — the result of antimicrobial resistance, or AMR — are a mounting threat to everyone. As a United Nations panel reported last year, “drug-resistant diseases already cause at least 700,000 deaths globally a year.” Unless we develop new and more potent antibiotics, that figure could increase to 10 million a year worldwide by 2050.

Scientists are well aware of this future dystopia — and have been ringing alarm bells for decades.

When antibiotics first became widely available in the 1940s, they revolutionized medicine by offering a way to cure deadly infections. But in the seven decades since — thanks in large part to overuse and misuse — some bacteria have evolved into new, drug-resistant strains. In short, what doesn’t kill bacteria makes them stronger.

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