It starts out with symptoms similar to a common cold, but it could cause paralysis.
Now, four cases of the rare and mysterious polio-like condition affecting children have been diagnosed in New York.
State health officials who are investigating the cases have not revealed details regarding the locations, ages, gender or any other identifying details about those affected.
So far, 127 cases in 22 states have been confirmed of acute flaccid myelitis or AFM, the CDC said.
The average age of those diagnosed is 4 years old.
It's unclear what's causing the outbreak, which can develop after a viral infection, environmental toxins, and genetic disorders.
AFM affects a person’s nervous system, specifically the spinal cord, causing weakness in one or more limbs.
For prevention, hand-washing is recommended by health officials, along with keeping hands away from the eyes, nose and mouth.
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