How changes in American behavior helped beat the winter surge: Shot

Restrictions on meals at meetings and indoors, improved mask wear rates, and increased social distance helped reduce the rate of new coronavirus infections in the United States.

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Restrictions on meals at meetings and indoors, improved mask wear rates, and increased social distance helped reduce the rate of new coronavirus infections in the United States.

He is suppressed / Getty Images

Updated 2:12 pm Eastern Standard Time

Coronavirus infections have been steadily declining in the United States over a six-week period, and it is clear that the worst days of the cruel winter surge have passed. Still, researchers are still uncertain how sustainable the decline will be.And although it is small, about the rise of the case In the last 3 days Health authorities are on the edge.

So what is the cause of the significant decline since January and what can the United States do to ensure that it persists?

New infectious diseases have declined by nearly 70% nationwide in just six weeks, with an average number of cases reaching the level last seen in early fall.

The number of people hospitalized with COVID-19 Plunge It increased by nearly 60% from its peak in January.Percentage of Test returns positive In the United States, it is well below its peak in January, from over 13% to less than 5% today.

And this trend applies almost everywhere. “It’s hard to find the county I’m concerned about, and it’s pretty impressive,” he says. Dr. David Rubin He directs the Policy Lab at the Philadelphia Children’s Hospital and uses localized data to model the outbreak of COVID-19.

The almost universal drop-off is different from the early waves of the pandemic. In the pandemic, cases tended to fluctuate one after another in different parts of the country.

“The seeds of risk aren’t hard to find and don’t just appear suddenly,” Rubin says. “The optimism is that you can’t see it. You can see it declining everywhere.”

Turnaround speed is also a good indicator that Americans are willing to do what they need to do to prevent the spread of the infection, says Natalie Dean. Associate Professor Majored in Biostatistics at the University of Florida. “When you see rapid change, you have to think about what can change rapidly, and human behavior is something that can.”

Dean says that high levels of infection and the expansion of the immune pocket from the vaccine are also helping more and more.

However, as new, more contagious variants are underway, top health officials in the country are worried that the decline may not be sustainable.

For spring, Rubin said it could counteract the potential dangers of the variant, including pandemic precautions, rising temperatures, and better attention to increased immunity to both infections and vaccination. There are multiple powers.

“The optimism is that if we can continue the current path of what we have learned to do well to protect each other and our family, it will hopefully lead to a path from this pandemic. There is, “he says.

What was useful? Americans “warned their hearts”

With more time spent indoors and more travel and family gatherings during the holiday season, it was not surprising that coronavirus infections surged during the colder months.

In some parts of the United States clearly There’s a big surge triggered by the holidays, but the overall “surge” that Dr. Anthony Fauci warned could happen this winter wasn’t as bad as some of the major illness modelers expected. did.

“It didn’t happen just because Americans changed their behavior,” he says. Arimokudad At the Institute for Health Metrics, University of Washington.

He says the overwhelming hospital news and constant reminders about the dangers of holiday gatherings resonated with Americans.

Data from Mokudad modeling Team track Mobility, cell phone activity, adherence to wearing face masks, etc., show that people have reduced travel and were less socially active during the holidays.

“”People really kept the warning in mind, and even those who traveled were left behind after the holidays, “says Mokudad, who points out that even mobile phones have fallen sharply as a result of Thanksgiving.

in progress Whole country According to a survey of more than 25,000 people in the United States, social distance has improved overall in recent months and is booming nationwide, resulting in “indoor proximity between groups of five or more.” Has reached its peak. “

We also found that about 30% of respondents attended or will attend a holiday gathering in December ()Comparison It will be only 15% in November).

“People are seeing these amazing numbers and they’re starting to pay attention,” he says. Dr. Salitasha, Associate Professor at the Rollins School of Public Health at Emory University.

Shah states that vaccination is still premature to have a significant impact on cases, but it will play a greater role in the coming months.

“Currently, this decline is entirely due to our control.”

Seasonality may continue to decline

The peak in mid-January and the subsequent decline are following the seasonal forces that epidemiologists are familiar with from other viruses.

“We haven’t left the forest yet, but during the winter we see a natural curve that reflects the seasonality of the virus,” said Rubin of the Philadelphia Children’s Hospital.

According to Rubin, there seems to be “a momentum of fewer cases towards spring” in many places. Many factors, including long days, rising temperatures in some parts of the United States, lack of large-scale rally leave in the near future, and accumulation of innate and adaptive immunity from vaccination, are due to more contagious mutations. He says it will overwhelm the risk.

Some parts of the United States have previously stated that immunity caused by high infection rates can be an important factor. Bill Hanage, Professor of Public Health, Harvard University.

More than 111,000 people in South Dakota Test positive For viruses since the outbreak of the pandemic, this is more than 12% of the population, and the actual number of infected people can be close to 41% in the state. According to a recent quote. Modelers estimate that more than one-third of the entire US population may already be infected.

However, Hanage says seasonal changes in temperature and increased immunity cannot fully explain why cases are declining at about the same rate in all regions.

“Everywhere there is a story of its own pandemic, but when I ask me that it’s more likely, I think it’s probably a mixed element of humans, as the weather is still pretty bad in most of the country,” Hanage said. I will.

According to an NPR analysis of Johns Hopkins coronavirus data, new daily infections have decreased by an average of about 82% in the West, about 73% in the Midwest, 68% in the South, and 61% in the Northeast over the past six weeks. ..

The danger ahead?

Despite advances in delaying infection, public health researchers are still seeing dangerous days before us. A well-known pattern throughout the pandemic is that mask wear and social distance improve when the situation is most dire, and fall again when the news improves, IHME’s Arimokudad warns.

“We are always on this roller coaster,” he says. “The question is, do Americans behave well when the incident is happening, so do they behave as if the incident was down?”

According to IHME, mask wear rates in February exceeded 75% nationwide, but mobility is already on the rise. Latest analysis..

Also, similar to COVID-19 hospitalization, cases remain much higher than at peak summer times.

according to In IHME modeling, the most likely scenario is that infections continue to steadily decline, dropping to about 35,000 new daily infections by May. A more pessimistic prediction of IHME is that coronavirus variants will spread rapidly, causing a new wave of infection in March, leading to a new small peak of about 126,000 new cases daily by April. ..

“Although the numbers are declining, there are some things that could cause the incident to surge again,” says Shah of Emory University. “It’s not time to be complacent.”

Some states already Abolish face mask obligations and restrictions on indoor meetings.

Foreseeing the emergence of new, more contagious variants of the virus in dozens of states, which can lead to sudden rebounds as seen in European countries such as the United Kingdom and Denmark. This can be a dangerous move.

“I thought we were facing a constant enemy,” says Natalie Dean of the University of Florida. “It depends on which variant is the most popular. I don’t consider them equivalent. You could get bigger hits with a particular type.”

First identified variant in the UK — Dr. Anthony Fauci The forecast is By late March, the predominant form of coronavirus could be treated with the Pfizer and Modana vaccines, according to available data.

For other strains first identified in South Africa and Brazil, pharmaceutical companies and the federal government are rushing to change available vaccines to catch up with mutations that may reduce their effectiveness. I am.

“These new variants are probably 20% to 30% more contagious,” says Shah. “Multiplying this by sending several cycles can lead to a spike in the number of cases.”