Acute flaccid myelitis, also called AFM, is a rare but serious condition that affects the nervous system - specifically, the area of the spinal cord called gray matter. In an email to doctors last week, the hospital said the children they've seen have had weakness in their arms or legs, and some have had to be admitted to the intensive care unit.
AFM cases on the rise in the U.S. Story continues below video. In 2017, one child who had AFM died, CDC said. They've been seeing an increase in cases since 2014.
"We have [had] two patients we have treated in CHEO for [acute flaccid paralysis] since the summer", said Dr. Sunita Venkateswaran, a pediatric neurogologist with the children's hospital.
AFP is the umbrella term used for "syndromes characterized by the acute onset of weakness of the limbs", including AFM, CDC notes.
"But that said, because we are seeing quite a few more cases than we would normally see, we certainly want our colleagues.to be aware of what to look for", he said of other practitioners and hospitals.
HuffPost Canada has reached out to the Canadian Paediatric Society for comment.
Although the symptoms of AFM have been described as "polio-like", polio has been ruled out as a cause in the USA cases, CDC said in a press conference. Some possible suspects, such as polio and West Nile virus, have been ruled out. "There isn't a consistent cause, and we don't understand the whole physiology behind it at this point". The average age of those affected is four.
It's unknown whether the paralysis will get better or remain the same.
Known as acute flaccid myelitis, the condition causes muscle weakness in one or more limbs, and typically occurs after some kind of viral infection. Several U.S. cases involved rhinovirus, which causes the common cold. While potential causes may include certain viruses, environmental toxins and genetic disorders, the CDC says, "AFM can be hard to diagnose because it shares numerous same symptoms as other neurologic diseases".
Venkateswaran said parents should seek medical help if their child is experiencing a sudden weakness in any part of the body, a sudden loss of bowl or bladder control, or neck pain.