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STEVE INSKEEP, HOST:
What is the cause of a mysterious childhood illness? This illness affects younger kids. It leads to limb weakness and paralysis. A new paper in the journal Pediatrics asks why and links this disease to a virus. NPR's Allison Aubrey reports.
ALLISON AUBREY, BYLINE: For kids who are hit with acute flaccid myelitis, or AFM for short, it comes on quickly. It usually starts with run-of-the-mill virus symptoms, such as a runny nose, a cough and fever. But then, in a terrifying turn, kids lose control of their limbs. That's what Susan Coyne, the mom of a boy named Evan, experienced.
SUSAN COYNE: Evan lost arm and legs. He could not move them. He couldn't lift them. He couldn't walk.
AUBREY: He was 7 at the time. He spent a year and a half in intensive rehab, learning how to walk and move his arms again.
COYNE: It was really scary, especially when, you know, this first started, no one knew what it was.
AUBREY: Researchers have now learned more about AFM. Here's Janell Routh of the CDC.
JANELL ROUTH: We know that AFM can be caused by multiple different things. But this paper really focuses in on viral cause.
AUBREY: In particular, a virus known as enterovirus D68. It turns out, during years when there's a lot of EV-D68 circulating in the U.S. - which tends to be every other year - there are also more cases of AFM.
ROUTH: And we're sort of seeing this trend in EV-D68 that mimics the trend in AFM.
AUBREY: Identifying a potential viral trigger is helpful, but enteroviruses, including EV-D68, are pretty common.
ROUTH: They are around all the time, and they cause lots of viral illnesses.
AUBREY: So it's not clear why a few hundred kids out of the many, many more exposed go on to develop AFM. Routh says that's still a mystery. Eventually, there could be a vaccine, but for now, she says, it's important for parents to know the symptoms.
ROUTH: If they notice limb weakness in their child or that facial droop, it's very important they see their physician right away.
AUBREY: Susan Coyne's son Evan has made a full recovery. He's back to playing baseball, living a full life. But there's a wide spectrum. Some kids with AFM are in wheelchairs and remain paralyzed.
Allison Aubrey, NPR News. Transcript provided by NPR, Copyright NPR.