The holidays are upon us.

The food. The festivities. Family and friends cramming onto trains and planes to gather for Thanksgiving dinner with Christmas and New Years right behind it.

COVID will surely follow.

The pandemic has taken a backseat this fall to the flu and RSV (respiratory syncytial virus), which have generated even more headlines.

But the coronavirus hasnt gone away, even if many people have put it behind them. And that worries experts.

I think that it would be really naive not to expect there to be somewhat of an increase in the number of cases, said Stephanie Silvera, an infectious disease expert and professor at Montclair State University. And that will result in an increase in hospitalizations. Simply percentage-wise, we know a certain number is going to end up in the hospital.

Experts see a rise in COVID-19 cases as an inevitability. They worry about the low turnout for the latest booster shot. They worry about rapid tests that are less accurate in detecting omicron subvariants. And they worry what a spike could mean as other respiratory illnesses like the flu and RSV continue to spread.

After all, omicron first appeared in New Jersey right after Thanksgiving 2021, leading to a tsunami that engulfed the Garden State by the end of December.

And if the past tells us anything, the holidays will almost certainly result in some sort of COVID surge. The question is: How bad will it be?

I think that we are poised for another surge almost regardless of holidays, said Dr. David Cennimo, an infectious disease expert at Rutgers New Jersey Medical School.

But the current COVID numbers are far from alarming.

Less than 1,000 coronavirus-positive patients were hospitalized as of Monday night, according to the states COVID dashboard. The transmission rate as of Monday was 0.89, meaning the pandemic was shrinking.

However, that could change in the coming weeks.

Testing is one issue. People are increasingly utilizing at-home antigen tests, which are less accurate than PCR tests, according to experts. They fear officials wont know the true number of cases until doctors offices and emergency rooms fill up.

We may not have data on how many more cases there are until those people show up at the hospital, for example, Silvera said. And so I think the challenge is that we may have an increase in cases that we wont be aware of until they show up for services, so it makes it a little bit harder for our hospital systems to plan.

She noted the antigen tests are not performing as well against subvariants like BA.4, BA.5 and BQ.1, which have become the dominant sublineages in New Jersey.

Its taking longer for those (tests) to turn positive, Silvera said. So people are testing on Day Three or Four. The rapid antigens are showing up as negative. Theyre going about living their lives theyre not necessarily wearing a mask.

And they might not actually have switched over to positive until Day Seven on one of those tests. So the probability for transmission is different.

Despite the release of the newest booster shot, turnout has been underwhelming. Only 35.3 million Americans received the bivalent booster shot, according to the Centers for Disease Control and Prevention. The bivalent shot was updated to combat two strains: the original novel coronavirus and the highly contagious omicron variant (and all of its subvariants).

That shot offers the highest protection against the strains currently circulating and is the best bet to avoid severe illness, experts say.

Cennimo is keeping his fingers crossed, hoping immunity holds for those who have yet to receive the latest booster.

That still seems to be showing pretty good protection against severe illness, hospitalization and death, Cennimo said, referring to the primary vaccination series. So hopefully that continues, but I think there will be more infections because were not boosting.

New Jersey is above the national average, with 14.1% of eligible residents having received the latest booster, according to the state Department of Health. However, that still means millions of eligible residents have yet to receive the shot.

If you havent gotten the bivalent vaccine, which is the one thats currently available, you dont have the best possible protection against severe illness for the currently circulating strains, Silvera said. And we know that the currently circulating strains have a lot of immune escape, meaning theyre more likely to cause you that more severe illness if you havent gotten the booster.

And then there are the other respiratory illnesses circulating. RSV and the flu which has reached high activity levels unusually early have been rampant. A surge in COVID-19 would only further strain hospitals.

I think this season is very unusual in the fact that you have three circulating viruses that we need to really heighten our concern. We have influenza, we have RSV which is currently affecting many children in the state of New Jersey and theres COVID, said Dr. Joseph Montella, chief medical officer at Cooper University Hospital in Camden.

Lately, things have been fairly quiet with COVID, he said, thanks to the vaccines.

He hopes it stays that way.

The hospitalizations for COVID have remained flat, Montella said. Then he added: Now that, of course, could change.

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Spencer Kent may be reached at skent@njadvancemedia.com.