A Research Model Predicts a Steady Decline in COVID-19 Cases Nationwide, but Local Experts Advise Caution

The latest analysis from the COVID-19 Scenario Modeling Hub, a consortium of researchers advising the Centers for Disease Control and Prevention, suggests that cases and deaths nationwide likely will decline steadily now through the spring without a significant winter surge.

The modelers developed four potential scenarios, taking into account whether or not childhood vaccinations take off and whether a more infectious new variant should emerge.

Hub researchers shared with NPR that the most likely scenario is that children under 12 get vaccinated and no new super-spreading variant emerges. In that case, the combo model forecasts that new infections would slowly, but fairly continuously, drop from about 140,000 a day now to about 9,000 a day by March 2022.

Deaths from COVID-19 would fall from about 1,500 a day now to fewer than 100 a day by March 2022.

That's around the level U.S. cases and deaths were in late March 2020 when the pandemic just started to flare up in the U.S. That scenario is also better compared to this summer when many thought the pandemic was waning.

While this may provide relief to some, researchers from the modeling hub and public health experts in the Bay Area present a clear caveat: The model makes several assumptions, and multiple existing variables could throw it all off.

"Any of us who have been following this closely, given what happened with delta, are going to be really cautious about too much optimism," said Justin Lessler, researcher with the University of North Carolina, who helps run the hub.

Lessler is especially worried about Pennsylvania, for example, and he notes that in some Western states like Idaho and Utah, there's a risk of resurgence.

Even California could lose the hard-fought progress it's made against the pandemic.

"What we've seen at many moments during the pandemic is that California, as a state, is doing better than the country as a whole," said Dr. Joshua Salomon, professor of health policy at Stanford, adding that the Bay Area is doing better than the rest of the state.

According to the CDC, California is reporting 94 cases per 100,000 residents and fits into what the public health agency considers "substantial" coronavirus transmission.

Compare that to other large states, like Texas and Florida, that are looking at figures twice, and in some cases three times, as big as California's. Florida counts approximately 296 cases per 100,000 residents while Texas registers 386 per 100,000.

High vaccination rates and strict public health restrictions are what's behind these numbers, Salomon says: "In the Bay Area counties, there's been a little more aggressive policies to try to contain transmission."

But Salomon is cautious. What this model forecasts — after all — is only a prediction.

"If you look at how well these long-term predictions have done in the past, there have been some pretty spectacular misses," he said, adding that the model largely depends on whether enough children get vaccinated.

As of Sept. 21, no pharmaceutical company has received approval from the federal government to distribute its COVID-19 vaccine to kids under 12.

Dr. Kirsten Bibbins-Domingo, professor of epidemiology and biostatistics at UCSF, takes the model's predictions positively but added that this is not the moment to let one's guard down.

"I don't think anyone is thinking that the virus magically disappears," she said. "Don't look at this model and think, 'I don't need to be vaccinated or there will never be a need for masks again.'"

She lists off three unknowns that could complicate the model: the arrival of winter and the potential surge that colder weather entails, the rise of another highly contagious variant like delta and the disparity of vaccination rates across California and the rest of the country.

"The wintertime is still a little bit of a danger zone because we tend to go inside during the winter months and the virus seems to like the weather of the cooler months," she explained.

Despite seeing new case numbers drop during the fall of last year, infections spiked across the country once winter arrived. On Jan. 9 of this year, California reported 28,514 new infections — the highest number of cases in a single day for the state. Three days later, on Jan. 12, the state reached its highest number of deaths in a single day: 702.

California has come a long way since then. It now ranks as one of the states with the highest vaccination rates in the country: Approximately 69.5% of residents have received both doses.

But a new variant could appear among the unvaccinated population.

"As long as the virus is circulating, new variants pop up," Bibbins-Domingo said.

Which is why, she adds, it's so important public health officials keep prioritizing vaccinations, especially among the areas in California with the lowest vaccination rates.

"We know that in California there is a lot of variation across the state," she said.

"Our coastal areas, particularly the big cities like San Francisco, have high vaccination rates and have weathered the delta surge fairly well, but the middle of the state, like the San Joaquin Valley, still have a lot of people at the hospital right now and they have lower vaccination rates."

Kern County, in the heart of the San Joaquin Valley, is currently reporting a seven-day average of 34.1 new coronavirus cases per 100,000, three times what San Francisco reported in the same period — 10.8 cases per 100,000 residents.

Kern also lags behind urban areas on vaccinations. More than three-quarters of eligible residents in the most populated Bay Area counties — San Francisco, Santa Clara and Alameda — are fully vaccinated. In Kern County, that number remains below 50%.

"We can't view that model as saying, 'The pandemic is over,'" Bibbins-Domingo explains. From her point of view, the vaccination gap between the big cities and rural communities may represent a bigger issue of health inequity.

"What this means is that vulnerable communities, whether that is low-income communities … or communities in the northern part of the state or in the eastern part of the state … will still be vulnerable as long as this virus continues to exist in our midst," she says.

This post includes reporting from KQED's Carlos Cabrera-Lomelí and NPR's Rob Stein and Carmel Wroth.