A POLIO-LIKE “mystery” disease has been rapidly spreading across the country, with most cases affecting children, the Centers for Disease Control and Prevention (CDC) said this week.
Although rare, acute flaccid myelitis (AFM) is a serious condition that affects the nervous system and causes the body’s muscles and reflexes, especially the legs and arms, to weaken. It also causes sudden paralysis in patients, especially in children.
Of the 127 patients who reported an AFM case in 2018, 62 AFM cases have been confirmed in 22 states.
The average age of confirmed AFM patients over the past five years is 4 years old, and of the confirmed cases, 90 percent are children, Dr. Nancy Messonnier, Director of the National Center for Immunization and Respiratory Diseases, said in a press briefing on Tuesday, Oct. 16.
“There is a lot we don’t know about AFM,” Messonnier told reporters. “The reason why we don’t know about AFM — and I am frustrated that despite all of our efforts we haven’t been able to identify the cause of this mystery illness — we continue to investigate to better understand the clinical picture of AFM cases, risk factors and possible causes of the increase in cases.”
Symptoms of AFM include drooping of the face and eyelids, difficulty with eye movement and swallowing and slurred speech. In more severe cases, patients might have difficulty breathing and may require a ventilator for muscle weakness.
Messionner said that AFM outbreaks tend to occur in the late summer and fall in a phenomenon she called “seasonal clustering,” and, so far, has only been detected in the United States. Since the outbreak has impacted many states, there is no evidence that the disease is concentrated on specific regions of the U.S., also known as geographic clustering.
Messonnier added that that although researchers have tested the disease extensively in laboratories, they have not determined the exact pathogen or immune response caused the weakness in arms and legs and paralysis in most patients.
There is one report of a child dying of AFM last year.
Since 2014, the rate of AFM diagnosis is less than one in a million. Medical and public health professionals are currently looking into whether environmental agents could be a factor in AFM, but confirmed that poliovirus is not the cause of AFM; none of the patients’ stool specimens tested positive for poliovirus.
“We know this can be frightening for parents,” Messionnier said. “This is a mystery so far and we haven’t solved it yet, so we have to be thinking broadly.”
While there is no specific treatment for AFM, neurologists might recommend treatments and interventions — such as physical or occupational therapy — on a “case-by-case basis,” according to the CDC. Doctors may perform a series of tests, including a magnetic resonance imaging (MRI) to examine the brain and spinal cord. Messionnier recommends seeking medical right away if a patient is exhibiting AFM symptoms.
“We want to encourage parents to seek medical care right away if you or your child develops symptoms of AFM, such as sudden weakness and loss of muscle tone in your arms or legs,” Messionnier said. “As we work to better understand what is causing AFM, parents can help protect their children from serious diseases by following prevention steps like washing our hands, staying up to date on recommended vaccines and using insect repellent to prevent mosquito bites.”