New model projects US COVID-19 cases could double in 2 months

FILE - A coronavirus drive-through testing center is seen in Bear Mountain, N.Y. on Nov. 25, 2020.

A new model from a study conducted by Washington University in St. Louis projected that COVID-19 cases in the United States could double by the time President-elect Joe Biden is inaugurated if the nation continues on its current trajectory.

The projection was made using a susceptible-infected-recovered (SIR) model, according to the study.

“The model, which accurately forecasted the rate of COVID-19 growth over the summer of 2020, was developed by Olin Business School’s Meng Liu, Raphael Thomadsen and Song Yao. Their paper presenting the model and its forecasts was published Nov. 23 by Scientific Reports,” according to Washington University’s publication, The Source.

The study forecasts four different models for four different levels of reopening amid the ongoing pandemic.

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The interactive models provided by the study show the projected number of COVID-19 cases depending on what level of “normalcy” (0%, 50%, 100% and current) the country goes back to.

For instance, if the country were to implement serious lockdowns with no chance for interactions among the population, overall cases in the U.S. could top out at a little over 11 million and plateau.

If the U.S. went to a 50% level of “normalcy,” overall cases in the nation would top out at about 15 million and plateau.

And if the U.S. continues as it currently has, the model projects the country will hit 20 million new COVID-19 cases by January 2021, nearly doubling in just two months.

Researchers also noted that the projections took into consideration the millions of Americans who have opted to travel for the holidays.

“In our model, we assume that only 10% of cases are ever diagnosed, meaning that we will start to hit saturation,” Song Yao, associate professor of marketing and study co-author, told The Source. “However, more recently, testing has increased, and probably more like 25% of cases are diagnosed. In that case, total COVID cases would increase beyond 20 million in the next few months unless we, as a society, engage in more social distancing.”

“The upcoming holiday seasons will present a great deal of uncertainty to the outlook of the pandemic as people travel more at the end of the year. This will likely make our forecast an optimistic one,” Meng Liu, assistant professor of marketing and study co-author, added.

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And while the U.S. Centers for Disease Control and Prevention as well as state and local authorities have begged people not to travel during the holidays, millions of Americans disregarded increasingly dire warnings that they stay home and limit their holiday gatherings to members of their own household.

About 900,000 to 1 million people per day passed through U.S. airport checkpoints from Friday through Wednesday, a drop-off of around 60% from the same time a year ago. Still, those were some of the biggest crowds since the COVID-19 crisis took hold in the United States in March. On Wednesday, the more than 1 million people screened at airports was the largest number since the start of the pandemic.

The U.S. hit a record 89,954 COVID-19 hospitalizations as of Nov. 25, according to the COVID Tracking Project. It is the most hospitalizations for the novel coronavirus the U.S. has seen, even since the start of the pandemic.

On top of that grim milestone, the country has recorded more than 12.7 million coronavirus infections and over 262,000 deaths, according to Johns Hopkins data.

The Associated Press contributed to this report.