Confirmed cases of a rare, polio-like illness affecting mostly children are now up to 62 nationwide, the Centers for Disease Control confirmed Tuesday, with one child dying of the disease.
This unexpected spike in AFM, or acute flaccid myelitis, “is a mystery” to health officials, Dr. Nancy Messonnier, the director of the National Center for Immunization and Respiratory Diseases at the CDC, said in a press conference.
The CDC has received reports of 127 AFM patients in 22 states, and have been able to confirm 62 of those cases so far.
“The number we’re reporting today is substantially larger than in previous months this year,” Messonnier said.
AFM is a “rare, but serious condition,” that causes paralysis. Much like polio, which is considered extinct in the U.S., AFM targets the nervous system and spinal cord, which causes the paralysis, along with muscle weakness and respiratory failure.
Of the 62 confirmed cases, the average age of patients is just 4 years old, the CDC said, and 90 percent of cases are in children 18 or younger.
“We know this can be frightening for parents,” Messonnier said. “I urge parents to seek medical care right away if you or your child develops sudden weakness or loss of muscle tone in the arms or legs.”
Concerningly, the CDC is unsure why there’s been a spike in AFM cases this year.
“We have not been able to find the cause for the majority of these AFM cases,” Messonnier said. “There’s a lot we don’t know about AFM, and I am frustrated that despite our efforts we haven’t been able to identify the cause of this mystery illness.”
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“Despite extensive laboratory testing, we have not determined what pathogen or immune response caused the arm or leg weakness and paralysis in most of these cases. We don’t know who might be at a higher risk of developing AFM, or the reasons why they would be at a higher risk. And we don’t fully understand the long-term consequences of AFM,” she added. “We know that some patients diagnosed with AFM recover quickly, and some continue to have paralysis and require long-term care.”
They have, however, been able to confirm that the polio virus is not one of the causes.
“The CDC has tested stool specimens from every one of the patients. Not one of them has tested positive for the polio virus,” Messonnier said.
The CDC first started tracking AFM in 2014, after a similar spike in cases. But despite the high number of patients this year, Messonnier emphasized that AFM is still extremely rare.
“Overall the rate of AFM is less than one in a million, and that’s why we say this disease is incredibly rare,” she said.
And while the CDC works to determine the cause of this rise of AFM cases, Messonnier encourages parents to have their children remain diligent about washing their hands, and to stay up-to-date on immunizations.