Acute flaccid myelitis (AFM), a rare polio-like disease in children, gained attention in 2014 after a large number of cases were reported. Centers for Disease Control and Prevention (CDC) has been thoroughly investigating AFM cases since then, and in October 2018, six children in Minnesota were hospitalized with the disease.
“The cause of the diagnosis isn’t fully understood,” said Dr. Scott Olson, a pediatric infectious disease specialist at Marshfield Clinic Health System. “It seems to be a very small minority of patients who develop this neurological disease.”
CDC estimates that less than one to two in a million children in the U.S. get AFM every year.
Rare but serious condition
In 2014, a cluster of pediatric patients during the winter months began experiencing nerve weakness. AFM affects the nervous system, specifically the area of the spinal cord, which causes the muscles and reflexes in the body to become weak. CDC found this coincided with a national outbreak of severe respiratory illness caused by enterovirus D68 (EV-D68).
“The fact that they found this virus in a number of patients with acute flaccid myelitis makes us think there’s a connection between the two,” Olson said. “When you look into what D68 causes, it typically is a respiratory virus, but it is within the enterovirus family – polio is an enterovirus.”
CDC states more than 90 percent of the patients with AFM had a mild respiratory illness or fever consistent with a viral infection before they developed AFM.
Viral infections such as from enteroviruses are common, especially in children, and most people recover,” reported CDC. “We don’t know why a small number of people develop AFM, while most others recover. We are continuing to investigate this.”
Symptoms of AFM
As stated, patients develop a mild respiratory illness prior to signs of AFM. Because respiratory illnesses are common throughout the year, Olson said parents should look for any signs of limb weakness.
According to CDC, most develop sudden arm or leg weakness. In addition, children may have difficulty moving their eyes, facial drooping or difficulty swallowing or slurred speech.
If you are concerned about your child’s symptoms, schedule an appointment with your pediatrician for evaluation. It is important the tests are done as soon as possible.
How to prevent AFM
While AFM is still under investigation, Olson said it’s important to keep routine hygiene and good respiratory etiquette to prevent illnesses like AFM. Hand washing is highly encouraged.
For more information on what CDC is doing, see AFM Investigation page.