"It's a common cold virus," said family medicine expert Dr. Marilyn Chohaney. "Lots of children get RSV, but it looks just like a cold."
Dr. Chohaney says there's no way for parents to tell the difference unless doctors test for it, or the symptoms become very severe, like wheezing and interrupted breathing.
"It can cause a kind of potentially damaging lung disease in very young infants if it takes hold," said Dr. Chohaney.
That's why government researchers are trying to document and monitor how many respiratory illnesses are caused by RSV. Researchers estimate 2.1 million kids contract RSV infections every year that are serious enough to require medical attention, but the vast majority are treated at their pediatrician's office.
Three percent are hospitalized, researchers say.
"It's being tracked carefully in the hopes that more can be done in the future," said Dr. Chohaney.
But for now, experts like Dr. Chohaney say your best defense is to wash your hands, just like you would with any cold virus.
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