The Only Way We’ll Know When We Need COVID-19 Boosters
Midway through America’s first mass-immunization campaign against the coronavirus, experts are already girding themselves for the next. The speedy rollout of wildly effective shots in countries such as the United States, where more than half the population has received at least one dose of a COVID-19 vaccine, has shown remarkable progress—finally, slowly, steadily beating the coronavirus back. But as people inch toward something tantalizingly resembling pre-pandemic life, a cloud hangs over our transcendent summer of change: the specter of vaccine failure. We spent months building up shields against the virus, and we still don’t know how long we can expect that protection to last.
To keep our bodies from slipping back toward our immunological square one, where the virus could pummel the population again, researchers are looking to vaccine boosters—another round of shots that will buoy our defenses. Around the world, scientists have already begun to dole out these jabs on an experimental basis, tinkering with their ingredients, packaging, and dosing in the hope that they’ll be ready long before they’re needed.
When exactly that will be, however, is … well, complicated. Nearly all the experts I spoke with for this story said that the need for boosters is looking more and more likely,
