By Stephanie Stahl

PHILADELPHIA (CBS) — There is a sharp increase recently in the number of children with COVID-19, but there is also a surprising spike in the number of kids being infected with another virus that usually strikes in the winter. It’s a double whammy of infections.

These are two different kinds of respiratory infections, and they’re both very contagious and on the rise across the United States, including in the Philadelphia region.

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Pediatric hospitals like St. Christopher’s Hospital for Children are getting bombarded again with sick kids. Not just with COVID-19, but there’s also been a surge of RSV, a different kind of respiratory infection.

RSV impacts the lungs and breathing passages. It causes cold-like symptoms, including cough, congestion and fever.

“We are seeing volumes which would be equivalent to a reasonably moderately busy wintertime month,” St. Christopher’s Hospital for Children Chief Medical Officer Dr. Doug Thompson said.

Thompson says RSV usually spikes in the winter, but it’s spreading now ironically because of COVID-19 precautions taken in the winter that also prevented RSV infections.

“Now, we have a large group of people who are truly at risk because we haven’t built up that immunity,” Thompson said.

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There is no specific treatment for RSV, and while most cases are mild, some children — like this 9-month-old baby — need help to breathe in a hospital.

“He would have coughing bouts where he was choking,” Kate Crowell, a mom, said.

With the coronavirus, almost 72,000 children and teens were infected with COVID-19 last week, marking an 84% jump, according to the Academy of Pediatrics.

“We have a lot of concern about that because we know the Delta variant is prevalent in our community,” Thompson said.

COVID is spreading among children under 12 who can’t be vaccinated and also among older teens who are eligible but haven’t been vaccinated.

“There’s a lot of vaccine hesitancy,” Thompson said. “We are situated in an area of Philadelphia where there are a lot of social challenges, not everybody has the same access to vaccine.”

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Doctors say it’s especially important for children and teenagers to wear masks in group settings when they’re inside.

Stephanie Stahl