New variant, family gatherings could lead to more Covid-19 after holidays, but experts don’t expect serious surge

CNN
—

With millions of Americans traveling to gather with friends and family in the coming days, it’s entirely possible that Covid-19 will continue.

Experts hope the Thanksgiving gathering will spur social networks and give new pockets of vulnerable people susceptible to the new coronavirus variant. , there may be an increase in cases and hospitalizations after the holidays.

Covid-19 is no exception in this regard. Thanksgiving gatherings can amplify the spread of other viruses, particularly respiratory syncytial virus (RSV) and influenza, both of which are already at high levels at this time of year.

“In some areas, we have seen a downward trend in RSV numbers. Flu cases are still trending upward. We are also concerned that it could increase,” Dr. Rochelle Wallenski, director of the U.S. Centers for Disease Control and Prevention, told CNN on Tuesday.

But things are relatively quiet on the Covid-19 front. Experts say it may not last long.

“The prevalence of COVID-19 is rising,” said Cisiluo, associate director of bioinformatics and infectious diseases at Helix, a genetic testing company that monitors coronavirus variants. In Helix sampling, “the fastest increase is between the ages of 18 and 24.”

Test positives in Helix data rose for the first time since July.

A rising positive test rate means a higher percentage of Covid-19 tests are returning a positive result, which could indicate an increase in infections.

“We should expect more cases,” Luo said. “I don’t know if they’re measured in the way cases are currently measured, but in general, I think we need to see more people who are sick. I definitely do.”

Since people are mostly testing for Covid-19 at home and not reporting their results, official counts may not detect an increase in cases as quickly.

The BQ variant of Omicron has now dominated infections in the United States. BQ.1 and its derivatives BQ.1.1 is a descendant of BA.5. They have five and six key mutations in their spike protein, respectively, which help them evade immunity caused by vaccines and infections.

For the week ending November 19th, Estimation of CDC Its BQ.1 and BQ.1.1 caused about half of all new Covid-19 cases in the United States. But so far they’ve gotten the upper hand without much impact.

Covid-19 cases, hospitalizations and deaths have leveled off over the past four weeks.But it’s not gone: over 300 on average americans die 3,400 people hospitalized every day With Covid-19, according to CDC data.

No one knows what the BQ variants will be. Many experts say they hope we won’t see the big waves of the past winter, and it’s nothing like the original Omicron variant.

There are many reasons for optimism.

First, there is the experience of other countries such as the UK, where BQ.1 has beaten its rivals to dominate infections, with cases, hospitalizations and deaths. fellThe same thing happened in France and Germany, says Michael Osterholm, an infectious disease expert who heads the Center for Infectious Disease Research and Policy at the University of Minnesota.

“Just before the subvariant entered, the number of cases increased in France and Germany. Then the subvariant entered and the number of cases actually decreased,” he said.

Bill Hanage, an epidemiologist at the Harvard TH Chan School of Public Health, believes that our behavior and social contacts are factors that determine whether this epidemic will increase.

He thinks we’ll likely see an increase in cases that could peak around the second week of January, as in previous years, but it’s unlikely that it will have a significant impact on hospitalizations and deaths. I don’t think so.

That’s probably because BQ.1’s benefits are gradual rather than dramatic, says Andrew Pekos, a virologist at the Johns Hopkins Bloomberg School of Public Health.

“It’s probably a bit more of a fitness benefit, so we’re seeing a gradual replacement without a big change in total Covid-19 cases,” he said.

It’s not that BQ.1 and BQ.1.1 have no effect at all. They have shown remarkable resistance to antibodies that can be used to protect and treat people vulnerable to severe Covid-19 infection. There are good reasons for people to be cautious when they are around someone who is.

But these subspecies will land when herd immunity is at an all-time high thanks to vaccines and infectious diseases. This is a very different setting from the virus Omicron encountered when it emerged a year before him, and it should also help dampen the wave ahead, Pekosz said.

“Right now, many people are getting boosted and vaccinated, and people have some immunity from Omicron infection, so the population context in which subspecies emerge is very, very different,” he said. “I think all the indications are the best part of the scenario, in that we don’t see a significant increase in cases.”

If there is reason to worry about BQ in the US, it could be: CDC data shows that two-thirds of the population has completed the initial series of Covid-19 vaccines, and only 11% of those eligible get their bivalent booster renewed. In the UK, 89% of the population aged 12+ has completed the primary series, with 70% boosted.

A new study shows that a country’s vaccination coverage is more important than any other factor when it comes to the impact of variants on the population.

Los Alamos National Laboratory scientists recently completed Investigation Delve into what caused the impact of 13 dominant coronavirus variants in 213 countries as they transitioned from one to another. This study includes data up to the end of September and was published as a preprint prior to peer review.

Of the 14 variables that influenced the speed and height of the new Covid-19 wave, population vaccination coverage was by far the most important.

The number of previous cases in the country, the percentage of people wearing masks, the median income, and the percentage of the population over 65 were second, third, fourth and fifth respectively.

Senior research author Bete Korver, a lab fellow in the Theoretical Biology and Biophysics Group at Los Alamos, said how well other variants coexist when new variants emerge is also an important factor. I’m here.

She points to the Alpha variant, B.1.1.7, and how it performed in the UK and US.

“It was very fast when it went through England, but much slower in the Americas,” Korver said.

By the time Alpha reached the US, we had evolved our own variants from California and New York. That role is here.

The CDC is tracking more than 10 Omicron subspecies soups causing cases in the United States, and their diversity may help dampen waves during the winter months.

But Korber makes no predictions. She said it was too difficult to know what would happen, and she pointed to Asia as her source of uncertainty.

Asian countries have been battling waves caused by recombinant XBB, a subspecies with little presence in the United States. BQ’s subspecies came later, but she says it’s impressive against her XBB, which has a very high immune evasion ability.

“BQ really stands out,” says Korber. “So I don’t think it’s possible to say for sure yet what could happen in the United States.”

“For me, it’s a good time to wear a mask, if possible,” she said. Masks protect not only the wearer, but those around them. “And if you’re eligible and it’s the right time for you, get a booster,” especially as we gather around the table to feast with friends and family.

“It’s time to take a little extra care to prevent waves from happening that we don’t want to see, or at least make it a smaller bump,” Korber said.