The first case in Maryland this year was contracted September 21, a spokeswoman for the department said in an email. Cases of AFM are characterized by a sudden onset of arm or leg weakness and loss of muscle tone and reflexes.
Some possible causes being investigated by the CDC include enteroviruses, which affect the digestive system, and rhinoviruses - the infectious agents associated with the common cold.
Since 2014, 386 cases have been confirmed, the CDC said on Tuesday.
There are five cases of AFM in Maryland. Another kind of virus was found in only some of the cases. "There is a lot we don't know about AFM, and I'm frustrated that despite all of our efforts, we haven't been able to identify the cause of this mystery illness".
Federal health officials released the updated numbers on Tuesday, and said they still had no idea what was causing the spike in AFM cases or why kids were getting it in the first place.
The agency says there are several possible causes, including "viruses, environmental toxins, and genetic disorders". Cases have been reported from the Twin Cities, central Minnesota and northeastern Minnesota. The Florida Department of Health said one case has been reported this year.
"This is actually a pretty dramatic disease", she said.
In some individuals, health officials have determined that the condition was from infection with a type of virus that causes severe respiratory illness.
This year, five children in Maryland have come down with AFM symptoms, according to the Maryland Department of Health.
But the agency doesn't know who may be at higher risk nor why they may be at higher risk.
There is no specific treatment for AFM, but neurologists who specialize in treating brain and spinal cord illnesses may recommend certain interventions, such as physical or occupational therapy, on a case-by-case basis.
Cases have been confirmed in 22 states.
The CDC referred calls to individual state health departments.
The CDC received information on 33 confirmed cases of AFM across 16 states in 2017, 149 cases in 39 states In 2016, 22 across 17 states in 2015 and 120 across 34 states in 2014. But Messonnier said that, in general, parents can help protect their children from diseases by washing their hands, making sure their children are up to date with vaccinations and applying insect repellent to protect against mosquito bites, which can spread viruses.
Kate Fowlie, a spokeswoman for the CDC, said in an email that many states are voluntarily reporting their data on the disease and that "many parents are coming forward to tell their stories".