Federal health officials have confirmed 10 new cases of a very rare but serious nervous system condition that causes weakness in the arms or legs, mostly in children.
The Centers for Disease Control and Prevention said 72 cases of acute flaccid myelitis, or AFM, have been confirmed in 24 states so far this year.
Two weeks ago, there were 62 confirmed cases in 22 states. Pennsylvania has three confirmed cases and one suspected case.
The CDC said another 119 cases are being investigated.
Health officials have seen an increased number of people across the United States with AFM since August 2014 and still don’t know the cause of most cases.
There were similar waves of the same illness in 2014 and 2016, both peaking in October.
About 90 percent of the patients have been children, and their symptoms have been most similar to those caused by certain viruses, including poliovirus and West Nile.
The CDC says it’s important to practice disease prevention steps, such as staying up-to-date on vaccines, washing your hands, and protecting yourself from mosquito bites.