The flu, COVID-19, RSV: Why everyone is getting sick

If you’re feeling under the weather lately – you’re not alone. 

According to the Centers for Disease Control and Prevention (CDC), seasonal influenza activity remains elevated nationally, and more than 20,000 people were admitted to the hospital for COVID-19 last week. 

Despite data released Friday showing a continued drop in flu hospitalizations, other indicators were up – including the number of states with high or very high levels of respiratory illnesses.

The agency said cases have ticked up 16.2% compared to last week, and in some regions of the United States, the flu virus is intensifying after weeks of an apparent national decline.

A sick woman lies in bed wearing a surgical mask. (Credit: Ute Grabowsky/Photothek via Getty Images)

"Nationally, we can say we've peaked, but on a regional level it varies," the CDC’s Alicia Budd told the Associated Press. "A couple of regions haven’t peaked yet."

Academic officials also recently cited concern over the high number of school absences due to various illnesses.

But what is contributing to a higher number of hospitalizations and respiratory illnesses?

Flu, COVID-19 cases elevated

Tracking during flu season relies in part on reports of people with flu-like symptoms who go to doctor’s offices or hospitals. But, many people with the flu are not tested, so their infections aren’t lab-confirmed.

COVID-19 and other respiratory viruses can sometimes muddy the picture, as well.

Alicia Budd, who leads the CDC’s flu surveillance team, said several indicators are showing "continued increases" in flu.

There are different kinds of flu viruses, and the version that’s been spreading the most so far this year usually leads to a lesser amount of hospitalizations and deaths in the elderly — the group on whom flu tends to take the largest toll.

People skipping flu, COVID-19 vaccines

Health experts also said that a growing number of people have been abandoning pandemic-era safety measures – skipping out on flu and COVID-19 vaccines this season – and this could be contributing to the higher number of illnesses they are seeing.

 "Pandemic precautions… those things are dwindling. And hence we're being exposed to more respiratory viruses than we have last year," Libby Richards, an associate professor at Purdue University School of Nursing told FOX News.

The CDC has reported decreases in the number of Americans rolling up their sleeves for the coronavirus shot. Richards noted that roughly 10 million fewer children and adults received the flu shot this year.

RELATED: Flu cases surge across US, CDC reports

Despite this, flu vaccination rates still fare better than rates for the other two main respiratory viruses — COVID-19 and RSV. About 14% of adults and 5% of children have gotten the currently recommended COVID-19 shot, and about 13.5% of adults 60 and older have gotten one of the RSV shots that became available earlier this year.

And with so many different respiratory viruses going around, Richards added that it’s likely that some people are becoming infected with different viruses back to back.

"Compared to this time point last year, we are seeing a higher rate of hospitalizations from the flu and RSV," she continued.

She said the best way to protect yourself from things like the flu and COVID-19 is to get vaccinated. Doctors and other health experts urge everyone 6 months and older to get an annual flu vaccine. 

Health experts said that there is still time to get a flu shot if you haven’t gotten one yet, citing how a second surge is always possible and cases can last until May.

FOX News, the Associated Press contributed to this story.

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