The Delta Variant Will Drive A Steep Rise In U.S. COVID Deaths, A New Model Shows
Front-line workers at a medical center in Aurora, Colo.,
gather for a COVID-19 memorial on July 15 to commemorate the lives lost
in the coronavirus pandemic. New estimates say many thousands more will
die in the U.S. this summer and fall.
Hyoung Chang/MediaNews Group/Denver Post via Getty Images
The current COVID-19 surge in the U.S. — fueled by the highly contagious delta variant
— will steadily accelerate through the summer and fall, peaking in
mid-October, with daily deaths more than triple what they are now.
That's according to new projections
released Wednesday from the COVID-19 Scenario Modeling Hub, a
consortium of researchers working in consultation with the Centers for
Disease Control and Prevention to help the agency track the course of
the pandemic.
It's a deflating prospect for parents looking
ahead to the coming school year, employers planning to get people back
to the workplace and everyone hoping that the days of big national
surges were over.
"What's going on in the country with the virus is matching our most pessimistic scenarios," says Justin Lessler,
an epidemiologist at the University of North Carolina who helps run the
modeling hub. "We might be seeing synergistic effects of people
becoming less cautious in addition to the impacts of the delta variant.
"I think it's a big call for caution," he adds.
The
group's latest projections combine 10 mathematical models from various
academic teams to create an "ensemble" projection. It offers four
scenarios for its projections — varying based on what percent of the
population gets vaccinated and how quickly the delta variant spreads.
In the most likely scenario, Lessler says, the U.S.
reaches only 70% vaccination among eligible Americans, and the delta
variant is 60% more transmissible.
In that scenario, at the peak in mid-October, there would be around 60,000 cases and around 850 deaths each day, Lessler says.
Each
scenario also includes a range of how bad things could get — the very
worst end of the range for the most likely scenario shows about 240,000
people getting infected and 4,000 people dying each day at the October
peak, which would be almost as bad as last winter.
Lessler
notes that there's a lot of uncertainty in these projections and that
how things actually plays out depends on lots of factors, including
whether the vaccination campaign picks up steam and whether other
mitigation measures are put back into place.
"Changes in behavior that we didn't predict and big shifts in vaccination could very much change these results," Lessler says.
But overall, the main projection shows a steady slope upwards to the peak in October, and then a steady slope back down.
"By
the time you get to October, these resurgent epidemics have burned
through a lot of the people who are susceptible," Lessler explains.
At
that point, "herd immunity starts kicking in a little more aggressively
and we start to see things going down again." By January 2022, the
model shows deaths coming back down to around the current level of about
300 per day.
The take-home message of this latest model is that the
pandemic isn't over yet and "we're not going to be able to land the
plane without turbulence," says William Hanage,
an epidemiologist at the Harvard T.H. Chan School of Public Health.
"How much turbulence will track with how many people are vaccinated in a
given community."
"I also strongly suspect that delta is
highly prone to superspreading — if I am right, it might go off like a
bomb in some undervaccinated communities," Hanage adds.
Public policy and behavior could still move the dial toward milder outcomes, Lessler says.
"I
think states should maybe be rethinking the speed at which they're
removing mask mandates or social distancing," Lessler says. "That is
something that — if you want to keep cases under control — certainly
would have an impact."
Those measures would have to come from state or local leaders. Despite calls for the CDC to issue new mask guidelines, at a briefing Thursday, CDC Director Rochelle Walensky once again held firm.
She
emphasized that the guidelines have always said that unvaccinated
people should wear masks indoors. She added that even vaccinated people
could wear masks indoors, too, if they want extra protection, especially
in places where the virus is surging and there are a lot of
unvaccinated people. But her main message was the same: Get vaccinated.
With that, Lessler agrees. "If we got enough people vaccinated, we could even stop the delta variant in its tracks," he says.
Posts
No comments:
Post a Comment