The Omicron wave looks swift and painful — some scientists expect US cases to peak in January and bottom out in March

• The US Omicron wave could peak sharply in January, then bottom out in March, new models suggest.
• Omicron could represent the swiftest outbreak in the US to date, lasting no more than three months.

Almost as quickly as the Omicron variant has torn through the US, some scientists are predicting it will decline. New models suggest that the US's Omicron outbreak may peak in January and last no more than three months.

That would make this latest wave much steeper and swifter than its predecessors.

"When you have something that goes up this quickly, often you see it come right back down," Dr. Anthony Fauci told "Good Morning America" on Tuesday. "Because what will happen is that almost everyone is either going to get infected, particularly the unvaccinated, or be vaccinated."

A recent report from the University of Texas estimated that Omicron cases could peak between January 18 and February 3, depending on how well the variant transmits or evades immunity relative to Delta. At the height of the winter surge, COVID-19 cases could reach between 230,000 and 550,000 a day, the model suggests.

The US has been recently reporting about 170,000 daily COVID-19 cases on average, as shown in the chart below from the Centers for Disease Control and Prevention.

Daily COVID-19 cases could also bottom out in March, the report said, even as Omicron remained prevalent. Another model from the University of Washington's Institute for Health Metrics and Evaluation (IHME) projects that coronavirus infections may peak at more than 2.8 million cases a day around January 27, then drop to fewer than 700,000 daily infections by April.

That trajectory wouldn't be surprising, scientists say: A highly transmissible virus tends to burn quickly through a population until it runs out of people to infect — and Omicron could be the most transmissible coronavirus variant to date.

"As the transmission moves from an outbreak setting to a household setting, where you're really starting to talk about infecting one or two people at a time, then you see that growth slow down," David Dowdy, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health, told Insider.

"Anytime you see these new outbreaks popping up, they start off with a bang," he added. "It doesn't mean that they're going to stay that way forever."

Omicron already seems to have passed its peak in South Africa, which first reported it to the World Health Organization, roughly one month after scientists first spotted it there. Daily COVID-19 cases in South Africa have fallen 24% on average over the past week after reaching a record high of nearly 38,000 cases on December 12.

But widespread Omicron cases could still bring a punishing surge of hospitalizations in the US.

"Even in my own hospitals that I work at, we're already starting to see more and more cases of COVID," Dr. Vivek Cherian, a Chicago internal-medicine physician, told Insider.

Both hospitalizations and asymptomatic infections could rise

Daily coronavirus infections in the US could reach a record high by January, the IHME model suggests. But that doesn't necessarily mean that vaccinated people will get sicker: Early data indicates that Omicron causes less severe illness than Delta does, perhaps because more people have some degree of immunity against the coronavirus already, either from vaccines or natural infection.

On the whole, hospitalizations and deaths are likely to rise the more Omicron spreads.

Omicron cases are doubling every two to three days in the US, and a recent report from Imperial College London suggested the variant increased the risk of reinfection by more than fivefold compared with Delta.

Within two to three months, more than 60% of all Americans could be infected with Omicron, the IHME model indicates. According to the model, more than 90% of those Omicron cases will likely be asymptomatic, but deaths could still increase considerably in January.

IHME predicted that COVID-19 deaths would peak around February 4 at more than 2,000 a day. The University of Texas' model suggests hospitalizations may climb to roughly 10,000 to 30,000 a day, while deaths could reach between 1,500 and 3,900 a day.

"Under all scenarios, we expect that Omicron will quickly overtake Delta as the dominant variant and has the potential to cause the most severe COVID-19 healthcare surges to date," the University of Texas researchers wrote.

Staffing shortages at hospitals, combined with a large share of unvaccinated people, could make it particularly difficult to treat patients. More than 38% of Americans are either unvaccinated or have received just one dose.

"Hospital capacity is already strained in many states," Faheem Younus, the chief of infectious diseases at the University of Maryland Upper Chesapeake Health, recently told Insider. "We fear a repeat of early 2020, when surgeries were canceled and non-COVID care was impacted due to hospitals being overloaded with COVID."