The average age of patients confirmed to have the condition is just four years old, with more than 90 percent of all cases occurring in children 18 and younger. Very little is known about the cause of most of the AFM cases but neurological diseases like AFM are often linked to viruses including poliovirus, non-polio enteroviruses, adenoviruses and West Nile virus and environmental toxins. Although infectious diseases that target the motor nerves and spinal cord can, in theory, affect anyone, Kassam said AFM has a particular "predilection" for children.
"CDC has been actively investigating AFM, testing specimens and monitoring disease since 2014, when we first saw an increase in cases", Messonnier told reporters last week. The disease would paralyze the arms or legs of a person's body.
At least 62 other cases of AFM have been confirmed in 22 states this year, the Associated Press reported earlier this month.
"I think it is worrisome especially when we're not sure what's causing it", Dr. Bhargava says.
Dr. John Christenson is a professor of clinical pediatrics at Riley's Children's Health in Indianapolis. "Less than one in a million people in the United States get AFM each year", the CDC says.
"What happens is that with time you build immunity", said Christenson.
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Shah says the best thing parents can do is to "continue being good parents".
"We don't have a vaccine".
Since September, the Hospital for Sick Children in Toronto has also seen an increase in patients with symptoms typical of AFP, namely muscle weakness and a preceding viral illness, according to associate pediatrician-in-chief Dr. Jeremy Friedman. "Everybody should have a flu shot", said Christenson.
The Atlanta-based health agency is investigating into 65 additional possible cases.
Dr. Vogel also noted most of the reported cases in the U.S.so far have been in the northern regions of the country while the CDC reports cases worldwide.
The CDC urges parents to be aware of this illness and to seek medical care right away if family members develop sudden weakness or loss of muscle tone in the arms or legs.