Five possible cases of a rare, polio-like illness are under investigation in Maryland, a state Department of Health spokesperson confirmed to NBC4.
Acute flaccid myelitis, or AFM, affects the nervous system and can cause partial paralysis in children, NBC News has reported.
The five possible cases of AFM in Maryland all were reported this year, the spokesperson said.
Symptoms can include arm or leg weakness, facial drooping or weakness, difficulty moving the eyes, drooping eyelids, difficulty with swallowing or slurred speech, according to the Centers for Disease Control (CDC).
"The CDC will make a determination about the status of the cases under investigation based on clinical and laboratory information," the Maryland Department of Health spokesperson said in an email.
Nationally, 62 cases of AFM have been confirmed in 22 states this year. More than 90 percent of the cases reported have been in children 18 or younger.
The CDC says on its website that the number of AFM cases have increased since 2014 but says the illness remains "very rare." They have not confirmed the cause for most cases and don't know what led to the increase that began in 2014.
There is no specific treatment for AFM.