DENVER — Another case of a mysterious "polio-like" illness has been confirmed in Colorado.
Fifteen people, most of them children, have come down with AFM, acute flaccid myelitis, a disease that paralyzes the limbs, causes seizures, and makes it difficult to breathe.
Researchers at the University of Colorado School of Medicine are now infecting mice in an attempt to learn more about this.
That has taught them a lot about what the symptoms look like.
It's a very rare disease, affecting about one in one million kids. But, for families fighting it, it's also very real.
"Cooper's an active 13-year-old," said Amber Allen, whose son Cooper was diagnosed with AFM back in July. "I don't feel like I realized how severe it was."
Cooper is part of what appears to be a resurgence in AFM, which causes inflammation and damage to the spinal cord, weakening muscles to the point of paralysis in some cases.
Doctors like Joyce Oleszek at Children's Hospital and researchers at the CU School of Medicine are now leading the charge nationwide on studying and trying to understand AFM’s mysterious reappearance since a similar outbreak in 2014.
"Let's get children in quickly so we can get treatment started, diagnose them and help with recovery," Oleszek said.
The scary part is many cases are at first misdiagnosed because symptoms often mimic the common cold.
The virus’s symptoms can include coughing, shortness of breath and other breathing problems.
"He said my neck feels stiff and I felt him, and he had a fever,” Amber Allen said. “Those are the two main symptoms. I just chalked it up to another bug."
Doctors say if your child experiences any muscle weakness - get them in immediately.
"When a nerve has been injured - the earlier you see improvement - the better chance of not suffering long-lasting weakness," Oleszek said.
As for Cooper - he's making progress despite the long road ahead.
In his case, the disease has partially paralyzed his left bicep and his left deltoid.
The CDC is not ruling out any possible triggers—from infections to toxins, autoimmune reactions to bug bites.
While the exact cause is not yet known, doctors at Children’s and the CU School of Medicine are fairly confident in saying it's a virus picked up in the environment, enterovirus D68, and in Cooper's case, possibly Enterovirus A71.
Researchers also don’t know how to treat or halt AFM’s progress.
Cooper is undergoing intense rehabilitation on the east coast and in Denver. He might also need surgery.
"Knowing that it'll change what options are available for him, what he can and can't do," said Cooper’s dad, Danny Allen “How do we ensure he has the most fulfilling life possible?”
"It just changes the dreams that you have for them," Amber said.