The CDC has confirmed 10 more cases of a rare polio-like illness affecting children across the U.S.

The total number of cases this year is now 90.

Acute Flaccid Myelitis affects the nervous system, and in serious cases, could cause paralysis.

Almost all cases have been found in children under the age of 18.

Over 160 other cases are currently under investigation.

The CDC says the agency is working hard to find the cause of the outbreak.