Most affected by AFM will experience a sudden onset of weakness or paralysis in a limb, but some may also experience drooping face and eye muscles, difficulty swallowing or difficulty moving the eyes, according to the CDC.
The CDC does not yet know the long-term effects of AFM Some patients have recovered quickly, while others continue to have paralysis, it says.
What can cause the illness? It's possible that AFM has a variety of causes, including viruses (such as poliovirus and enteroviruses), environmental toxins and genetic disorders, the CDC says. Its origins are a mystery, but officials say a virus can cause some cases. The CDC also notes that the condition mostly affects children.
Even with an increase in cases since 2014, AFM is considered a very rare condition, with fewer than 1 in 1 million people in the USA getting the illness, the CDC said. To put the recent increase in perspective, the highest number of reported cases was 149 in 2016.
Luckily, he was diagnosed fairly quickly since a doctor at the hospital where he was treated wrote a paper on AFM.
"It's very, very rare - it's about one in a million", said Kris Ehresmann with the Minnesota Department of Health.
In its most severe form, AFM can lead to respiratory failure. It was announced on October 5 that six Minnesota children had developed the disease since mid-September and a case in Iowa was announced on October 10. All of those patients were under the age of 10 and were hospitalized around the middle of September, according to an October 5 news release. By the end of that year, 120 people had been diagnosed in 34 states.
The state typically sees just one or fewer cases of AFM a year, making the six cases extremely concerning.
"Of the AFM cases, 11 tested positive for enterovirus A71, one tested positive for enterovirus D68, and two tested negative for enteroviruses", the department said in an online statement Tuesday.
Both EV-D68 and EV-A71 are enteroviruses, and they are in the same family of viruses as polio.
Do patients make a full recovery? . "There have been no deaths". "Collecting information about suspected AFM cases is relatively new, and it is voluntary for most states to send this information to CDC".
"But we do know that over time, with rehabilitation therapies, numerous children can regain function". But in very rare cases, they can damage the nerves.