Lurching Between Crisis and Complacency’: Was This Our Last Covid Surge?

Rising immunity and modest changes in behavior may explain why cases are declining, but much remains unknown, scientists say.


Vaccinations at the Unidos En Salud community vaccination and testing site in San Francisco this summer. Infections are down more than 40 percent since August.Credit...Mike Kai Chen for The New York Times


By Emily Anthes
Oct. 14, 2021


After a brutal summer surge, driven by the highly contagious Delta variant, the coronavirus is again in retreat.

The United States is recording roughly 90,000 new infections a day, down more than 40 percent since August. Hospitalizations and deaths are falling, too.

The crisis is not over everywhere — the situation in Alaska is particularly dire — but nationally, the trend is clear, and hopes are rising that the worst is finally behind us.

Again.

Over the past two years, the pandemic has crashed over the country in waves, inundating hospitals and then receding, only to return after Americans let their guard down.

It is difficult to tease apart the reasons that the virus ebbs and flows in this way, and harder still to predict the future.

But as winter looms, there are real reasons for optimism. Nearly 70 percent of adults are fully vaccinated, and many children under 12 are likely to be eligible for their shots in a matter of weeks. Federal regulators could soon authorize the first antiviral pill for Covid-19.

“We are definitely, without a doubt, hands-down in a better place this year than we were last year,” said Dr. Nahid Bhadelia, director of the Center for Emerging Infectious Diseases Policy and Research at Boston University.

But the pandemic is not over yet, scientists cautioned. Nearly 2,000 Americans are still dying every day, and another winter surge is plausible. Given how many Americans remain unvaccinated, and how much remains unknown, it is too soon to abandon basic precautions, they said.

“We’ve done this again and again, where we let the foot off the pedal too early,” Dr. Bhadelia said. “It behooves us to be a bit more cautious as we’re trying to get to that finish line.”

When the first wave of cases hit the United States in early 2020, there was no Covid vaccine, and essentially no one was immune to the virus. The only way to flatten the proverbial curve was to change individual behavior.

That is what the first round of stay-at-home orders, business closures, mask mandates and bans on large gatherings aimed to do. There is still debate over which of these measures were most effective, but numerous studies suggest that, collectively, they made a difference, keeping people at home and curbing the growth of case numbers.

These policies, combined with voluntary social distancing, most likely helped bring the early surges to an end, researchers said.During last winter’s surge, for instance, the percentage of Americans who reported going to bars or restaurants or attending large events declined, according to the U.S. Covid-19 Trends and Impact Survey, which has surveyed an average of 44,000 Facebook users daily since April 2020.The fact that case numbers are falling does not mean that the country has reached herd immunity, a goal that many scientists now believe is unattainable. But the rising levels of vaccination and infection, combined with more modest behavioral changes, may have been enough to bring the surge to an end.