When the United States saw COVID-19 cases and deaths spike over Christmas and New Years, many Americans feared the country was experiencing a third winter wave.
But as quickly as both metrics rose, they also fell. Weekly cases and deaths in late winter 2022-23 are comparable to what was seen in spring 2022, according to data from the Centers for Disease Control and Prevention.
Last year, the Biden administration issued a dire warning that up to 100 million Americans could become infected during a fall and winter surge of COVID-19.
However, as the third anniversary of the World Health Organization’s declaration of the virus as a global pandemic passes, it looks like the United States has survived its first winter without a massive outbreak of COVID-19.
Experts told ABC News that a combination of more immunity, better treatments, less severe infections and more people on mitigation measures likely played a role.
“We didn’t see a surge because we had very high immunity from infections and vaccinations,” Dr. Ali Mokdad, an epidemiologist at the Institute for Health Measurement and Evaluation, told ABC News. the University of Washington in Seattle. “Omicron and its subvariants spared no one. In addition, many infections were minor and unreported or did not result in hospitalization.”
Comparison between winters
During the first winter wave, weekly cases peaked at 1,714,256 the week of Jan. 13, 2021, as did weekly deaths at 23,378, according to CDC data.
Subsequently, during the second winter wave – due to the omicron variant – weekly infections peaked at 5,630,736 the week of January 19, 2022, and weekly deaths peaked at 17,373 the week as of February 2, 2022, data shows.
By comparison, according to the CDC, the highest number of weekly cases seen during the last winter surge was 472,601 the week of December 7, 2023 – the first time the peak has not exceeded 1 million.
Meanwhile, weekly deaths peaked at 4,448 the week of January 11, 2023, five times lower than the peak of the first winter wave and nearly four times lower than the peak of the second wave.
Dr. John Brownstein, epidemiologist and chief innovation officer at Boston Children’s Hospital and ABC News contributor, said there was some inconsistency when comparing past winter surges to this winter, as there was a lack of overall testing and reduced use of home testing this winter. winter.
However, the lower number of hospitalizations and deaths is likely a good indication of a less severe season this year compared to previous years, he said.
“Even though infections this winter were high in the community, hospitalizations were relatively stable compared to recent years,” Dr. Peter Chin-Hong, an infectious disease specialist at the University of California, San Francisco, told ABC News. . “A lot of us suspected it wouldn’t last very long.”
More immunity
Experts told ABC News that over the winters, greater immunity has built up in the population.
During the first winter wave, COVID-19 vaccines were not widely available. They only started rolling out in mid-December and only for specific groups, including healthcare workers and adults aged 65 and over.
By the time the second winter wave rolled around, most of the U.S. population had received a primary series, according to CDC data, and the first booster was available to the general population.
During this most recent winter, an updated bivalent booster is also available, which – although only 16.2% of the population received it – probably offered at least some protection.
“I think the reduction in severe disease is increased population immunity,” Chin-Hong said. “Just the percentage of people who have been exposed, and then you layer those vaccinations.”
Last year, the CDC estimated that by May 2022, more than 94% of the U.S. population had antibodies induced by COVID-19, either from prior infection or vaccination.
Evolution of treatments
Experts said another reason this season may not have been so bad for COVID is that we have more effective treatments.
During the first winter wave, remdesivir was the only drug approved to treat patients with severe cases of COVID.
However, clinical trial data was later published showing that the drug did not significantly reduce the risk of death in critically ill patients, but was more beneficial when given at the start of treatment.
Since then, we have seen the introduction of antiviral pills, including Molnupiravir from Merck and Ridgeback Biotherapeutics and Paxlovid from Pfizer.
Clinical trial data showed that Merck’s pill reduces the risk of hospitalization and death for patients with symptoms and at risk of serious illness by 30%, while Pfizer’s pill reduces the risk by nearly 90% .
People following mitigation measures
“I think the public consciousness around infectious disease has completely changed,” Brownstein told ABC News. “That wouldn’t necessarily mean for everyone, but for a large part of the population there is a hyper-awareness of infectious diseases that has led to significant behavioral changes.”
This means that even though mask mandates and other mitigations have been removed, everyday Americans are more mindful of staying home when sick, wearing a mask in public situations, or doing tests before attending a rally, experts say.
Chin-Hong said it was different from what he had seen in winters before the pandemic.
“Before the pandemic, people were walking around,” he said. “And because there’s a lot of awareness that testing (at home) can be negative early on for COVID, people have just stayed home and taken all measures and self-isolated.”
He added that it likely also helped protect people against other diseases that were circulating last winter, including influenza and RSV.
The importance of staying alert
Experts told ABC News it’s important to remain vigilant because a new, more transmissible variant or a new outbreak could easily lead to another wave in the United States.
“I think in general having a bunch of infections a year before helps the year after, because you pass on some immunity,” Chin-Hong said. “With COVID, who knows? It all depends on when people lose their immunity and the rules of reinforcement, which could happen in the fall.”
Earlier this year, it was revealed that the US Food and Drug Administration was considering a new COVID-19 vaccination strategy that would see Americans receive a single annual shot, similar to the flu vaccine.
According to briefing documents, the new approach would simplify public health messaging on when to get COVID vaccines, in hopes that making the advice easier for people to understand could potentially boost vaccination rates in states. -United.
“I think ultimately the trend will probably be towards less and less severe surges,” Brownstein said. “I don’t think it’s definitively predicted that we’ll always see smaller surges. There will be some variation that will result from factors like circulating variants, level of immunization in the population, behavior.”
He continued: “So we can’t fully predict, but the general trend over the coming year should be towards increasingly mild surges.”