Doctors are urging caution to prevent Covid-19 outbreaks as cases rise nationwide following a nearly three-week plateau and Americans prepare to celebrate Thanksgiving with friends and family next week.
The U.S. reported a seven-day average of nearly 95,000 new Covid infections Thursday, up 31% over the past two weeks, according to a CNBC analysis of data from Johns Hopkins University. Cases across the country declined for weeks this fall before hovering between 70,000 and 75,000 per day beginning in late October, down more than 50% from the peak of the delta surge that ravaged the U.S. this summer.
But with the holiday season approaching and cold weather driving more people to meet indoors, public health officials are hoping to mitigate against another record-setting Covid wave this winter. Last Christmas preceded the country's worst-ever Covid spike with cases peaking at more than 250,000 per day on Jan. 11. Deaths from the virus also hit a pandemic high of roughly 3,400 per day in early 2021.
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The combination of Thanksgiving, Christmas and falling temperatures makes this time of year "the perfect storm" for Covid, Dr. Bruce Farber, chief of infectious disease at Northwell Health in New York, told CNBC.
Infectious disease specialists widely agree that it's safe to celebrate the holidays with friends and family as long as everybody's immunized against Covid. But a new study from the Ohio State University's Wexner Medical Center found that half of respondents wouldn't ask for the vaccination status of guests at their gatherings, and some 54% said they wouldn't request that unvaccinated partygoers test negative for the virus.
"I wouldn't allow anybody to go to Thanksgiving who's not vaccinated," Farber said. "I think that should be the price you pay."
With the effectiveness of Covid vaccines doses proven to wane over time, Farber advised fully vaccinated individuals to get their booster shots for an additional layer of protection during the holidays. The Food and Drug Administration signed off on Pfizer and Moderna's booster shots for all adults in the U.S. on Friday.
Individuals vaccinated in the earliest stages of the rollout are susceptible to breakthrough infections, said Dr. Reynold Panettieri, vice chancellor for translational medicine and science at Rutgers University.
"I would anticipate that we will see an uptick in and around the holidays, just because people are going to be getting together with more exposures," Panettieri said. He noted, though, that progress in vaccination and treatment options means an outbreak this winter "will be nowhere near what it was before."
A downward trend in Covid hospitalizations and deaths, which typically lag reported case counts by a couple weeks or more as people become infected with the virus and then become sick enough to need urgent care, is showing signs of leveling off. Roughly 48,000 Americans are currently hospitalized with the virus, the same level as two weeks ago, based on a seven-day average of Department of Health and Human Services data. And the daily average of about 1,200 reported fatalities tracked by Hopkins is showing signs of an uptick after being little changed for two weeks.
Outbreaks in the Midwest and Northeast, where cases are up 56% and 47% over the past two weeks, appear to be driving the national numbers. Hospitalizations have risen by 20% and 7% there, respectively.
The Northeast's highly dense cities and the Midwest's colder temperatures – compared with the South, where cases have plunged as more comfortable weather rolls in – could help explain those regional differences, Panettieri noted.
"The weather drives people indoors, and the interest for more indoor activities certainly could ratchet up the experience," Panettieri said.
Besides vaccinating and boosting, Panettieri said those gathering for Thanksgiving should know whether their fellow attendees have been careful to avoid Covid exposure. But even with the risk of another outbreak looming this winter, advancements in immunizations and natural immunity among those who caught Covid during the delta surge have left the U.S. "much better off" this Thanksgiving than last, Dr. Arturo Casadevall, chair of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health, told CNBC in an email.
"Clearly, if people have any sort of respiratory symptoms such as colds or flu-like illnesses, they need to rule out COVID-19 by getting tested before getting together with their loved ones," Casadevall wrote. "Common sense, caution and vaccinations are good prescriptions for a safer holiday."