Doctors say that most of the reported cases of AFM involve those under the age of 18.
The surge in cases has baffled health officials, who on Tuesday took the unusual step of announcing a change in the way the agency will count cases in the future. The most severe symptom is breathing trouble. CDC officials say they haven't found the cause.
The increase in cases appeared to begin in 2014, when the CDC started tracking the illness. The CDC doesn't know what caused the spikes. Another spike came in 2016.
There were outbreaks of around 100 cases, nationwide, between August and October in both 2014 and 2016.
"This is actually a pretty dramatic disease", Messonnier told reporters on Tuesday.
"Nobody really knows treatment protocols, they don't know prognosis, and they can't really give parents an answer as to where this is coming from", she said.
The agency has not yet confirmed whether the New Hampshire patient, a juvenile from Rockingham County, contracted AFM or if it is another illness, said Jake Leon, a spokesman for the state Department of Health and Human Services.
States are reporting their cases to the CDC, Messonnier said.
"As a parent myself I understand what it's like to be scared for your child", Messonnier said. "Parents need to know that AFM is rare even with the increase in cases we are seeing now".
Some patients diagnosed with AFM were found to have enterovirus D68, a cousin of poliovirus, in their systems. "These symptoms that are similar to cold-like symptoms, with this particular virus, what is probably happening is something is causing an inflammation within the spinal cord". To help prevent the illness' spread, the CDC advises proper hand washing, staying up to date on vaccines and using mosquito repellent to avoid bites. There was one death of a child who had AFM, in 2017, said Messonnier. This year is one of them. No pathogen has been consistently detected in the patients' spinal fluid. "Most AFM cases occur in the late summer and fall", which she referred to as "seasonal clustering".
That's when we spoke with the families of 4-year-old Camdyn Carr, who's now fighting the disease, and 7-year-old Sebastian Bottomley, who previously fought AFM. "So we're very lucky that he had (physical therapy) through early intervention". It could be potentially deadly if the diaphragm is paralyzed because the child would be unable to breathe.
Cases have been reported in 22 states, including some in our area.