Covid hospitalizations are rising in the United States, even as hospitalizations for respiratory syncytial virus and flu continue to decline.

The Centers for Disease Control and Prevention reported on Friday that while the flu is still spreading at high levels, virus activity is declining in «most areas.» During the week ending December 24, about 18,800 people were hospitalized with the flu, up from 20,700 hospitalizations the week before.

RSV hospitalization rates have decreased significantly from their peak in mid-November of 5.1 hospitalizations per 100,000 people. For the week ending December 24, the rate was 0.8 per 100,000.

As of Thursday, data from the Department of Health and Human Services showed that children’s hospital beds across the country, which include children hospitalized with covid, RSV or flu, among other illnesses, were 66% full, compared to the 69% from a week ago.

Still, infectious disease experts urge caution. The country just celebrated Thanksgiving and Christmas and will soon celebrate the New Year, said Dr. William Schaffner, an infectious disease expert at Vanderbilt University Medical Center in Tennessee.

“We anticipate that, at least, the flu is going to resurface after all these trips and all these Christmas gatherings,” he said.

The drop in flu activity could also be the result of a delay in reporting over the holidays, Schaffner added.

So far this season, at least 20 million people in the US have been infected with the flu, according to the CDC. About 13,000 have died. Of the samples reported to the agency, about 83% are of the H3N2 strain of influenza A. The rest are H1N1, another strain of influenza A. Both can cause serious illness.

Covid, however, is bucking the trend.

The seven-day average of daily Covid hospitalizations reached 42,140 on Friday, an increase of 4.2% from two weeks ago, according to a tally by NBC News. The seven-day average of daily intensive care unit admissions also rose to 5,125 per day, an increase of more than 9% from two weeks ago.

Still, the number of Covid hospitalizations is not expected to reach the level it did last winter, when the original omicron variant, called BA.1, began to spread rapidly, said Dr. Isaac Bogoch, an infectious disease physician at the university of toronto

He said a combination of population immunity, either from previous infection, vaccination or both, and a host of new variants that appear to be less virulent have made the virus less of a threat this winter.

Even if another new variant emerges that is more resistant to vaccines, he said, Covid still shouldn’t cause as much disruption as in years past.

«The hope is that it will have less and less impact on health care systems and communities,» Bogoch said.

People can protect themselves by wearing a well-fitting mask and avoiding large, crowded settings, Schaffner said.

The CDC recommends up-to-date covid vaccinations for everyone over the age of 6 months, as well as annual flu shots. There is not yet a vaccine for RSV.

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