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The pandemic’s grip is loosening. As we reported last week, cases are down 57 percent from the country’s all-time peak in early January. For the first time since November, the United States saw a single day with fewer than 100,000 cases of COVID-19. Finally, a bit of relief.
“Some pandemic statistics are foggy,” our staff writer Derek Thompson notes, “but the current decline of COVID-19 is crystal clear.”
What’s driving that decline? Here are four reasons for it, as explained by Derek.
1. Behavior: Maybe Americans finally got the hang of this mask and social-distancing thing.
“If I were ranking explanations for the decline in COVID-19, behavior would be No. 1,” says Ali Mokdad, a global-health professor at the University of Washington, in Seattle. “If you look at mobility data the week after Thanksgiving and Christmas, activity went down.”
2. Seasonality: The coronavirus was perhaps destined to decline this time of year.
“Many viruses fare best in cold and dry conditions; they’re not well designed to thrive in warmer, sunnier, and more humid outdoor areas.”
3. Partial immunity: Is the virus running out of bodies?
Fifteen to 30 percent of American adults have already been infected with COVID-19, according to CDC estimates. Since people recovering from COVID-19 typically develop lasting immunological protection for many months (at least), the number of antibodies swirling around the U.S. population may naturally constrict the original coronavirus’s path forward.
4. Vaccines: The shots work.
The vaccines—especially the synthetic-mRNA vaccines from Pfizer-BioNTech and Moderna—are highly effective at preventing infection. But preventing infection is not all they do. Among those infected, they also reduce symptomatic illness.