AFM typically affects young children and creates polio-like symptoms. Four of the five had a fever of 100.4 or higher.
"Oftentimes, despite extensive lab tests, the cause of a patient's AFM is not identified", the CDC says.
Editor's Note: The video above was originally published in 2016.
On Tuesday, Sen. Klobuchar sent a letter to the Centers for Disease Control and Prevention urging them to investigate and respond to the recent increase in AFM cases.More news: Foster rejects Irish sea border after Barnier meeting
Also this week, the Colorado Department of Public Health and Environment announced that 14 cases of AFM have occurred in the state this year. "Isolation protocols and infection control procedures are in place and we're working with the CDC and the Allegheny County Health Department to further monitor and evaluate the patient conditions".
"The patients are now undergoing diagnostic procedures and treatment", said Andrea Kunicky, a spokeswoman for UPMC Children's Hospital of Pittsburgh, where the children are being treated. "So, we've seen that there's an association between viruses, specifically enterovirus, in the past". "Among the people confirmed with AFM, CDC did not consistently detect EV-D68 in every patient".
"But just because you catch the virus from somebody that developed AFM, doesn't mean that you will also develop AFM", Dr. Meade explained. Since then, more than 350 cases of the illness have been reported in the USA over a four-year period.
There were two other suspected cases of AFM in the state earlier this year, according to Schultz. But unlike polio, there is no vaccine for AFM.More news: Kate Middleton goes off-the-shoulder for night at the museum
In rare cases, the CDC stated, it can cause numbness, tingling and pain in the extremities, problems urinating, paralysis, respiratory failure and death.
Outside of IL, there are now a few dozen cases of AFM in the United States.
Though officials have observed a rise in cases since 2014, the condition's origins remain unclear.
Previously, only four cases had been reported in IL since 2015.More news: Dow Jones plunges 800 points as tech stocks tumble
The health department says there are no specific recommendations for avoiding AFM, but washing your hands, avoiding close contact with sick people, cleaning surfaces with disinfectants, and staying up-to-date on immunizations is recommended.