The CDC confirmed 10 additional cases of acute flaccid myelitis, bringing the total number of children infected with the rare, polio-like illness to 116 this year, reports CNN.
The CDC is still investigating another 170 potential cases of AFM, which has infected children across 31 states.
Colorado has the most infected children with 15 confirmed cases, closely followed by Texas with 14 cases. It is not known whether individuals in these states are more at risk of contracting AFM or if these states are just better at identifying and reporting cases, according to CNN. Twelve states have reported only one confirmed AFM case.
The CDC has confirmed 440 AFM cases since 2014, 90 percent of which occurred in children under age 4. The exact cause of the illness is still unknown.