• Infectious Diseases

    Acute flaccid myelitis: Don’t ignore the symptoms

a sick child sleeping in a hospital bed with an IV in his or her hand

Acute flaccid myelitis or AFM is a rare, polio-like condition that causes sudden weakness in a person's arms or legs and can lead to respiratory distress. Most often occurring in children, AFM can result in permanent disability, even death.

The Centers for Disease Control and Prevention is urging parents and caregivers to be on the lookout for symptoms of AFM, as most cases have historically emerged during the August to November.

Dr. Kenneth Mack, a Mayo Clinic pediatric neurologist says the specific cause of acute flaccid myelitis is still unknown, but it generally appears immediately after an infection.

"We think that there's a group of viruses called enterovirus that may play a role in this," Dr. Mack says. "And in the course of fighting the infection, what probably happens is that the body fights some of the cells within the spinal cord that control motor movement of these limbs."

Dr. Mack says that while acute flaccid myelitis has been identified for decades, there has been a dramatic increase in cases in recent years, with 2014, 2016 and 2018 having significantly higher rates than in the past.

Watch: Mayo Clinic physician discusses concerning increase in cases of acute flaccid myelitis.

Journalists: Broadcast-quality sound bites are in the downloads at the end of the post. Please ‘Courtesy: Mayo Clinic News Network.’

Dr. Mack says acute flaccid myelitis generally is not painful. But the CDC recommends parents look for these symptoms in their children:

  • Weakness and loss of muscle tone and reflexes in the arms or legs
  • Facial droop or weakness
  • Difficulty moving the eyes
  • Drooping eyelids
  • Difficulty swallowing
  • Slurred speech

The CDC reports that the long-term prognosis for children with acute flaccid myelitis is still unknown. Dr. Mack says children in some cases have shown significant improvement in their symptoms over time, while others have seen little to no improvement. At this point, treatment effort is focused mainly on improving symptoms – not curing the illness.

Since the cause of acute flaccid myelitis is still not understood, it's difficult to know how to prevent it. The CDC recommends staying up to date on all vaccinations and avoiding mosquito bites.

"The CDC [also] has recommended the types of normal hygiene stuff that we all should practice," Dr. Mack says. "So washing hands, cleaning surfaces, trying to stay home when you're sick or ill so you don't spread infection. And right now, that's probably the biggest impact we can make on this."