Over a dozen more cases of the rare polio-like paralyzing illness affecting children across the U.S. have been confirmed.

Sixteen more cases of Acute Flaccid Myelitis, or AFM, have been confirmed, bringing the total to 106 cases in 29 states this year.

AFM affects the spinal cord and could cause paralysis.

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

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