Ask the doctors: Acute flaccid myelitis seen mostly in children

Dear Doctor: What’s the latest on the new children’s disease that’s kind of like polio? It’s been all over the news, and like a lot of the moms around here, I’m getting worried.

Dear Reader: You’re referring to a rare and serious neurological condition that, as you mention, bears some striking similarities to polio. Known as acute flaccid myelitis, or AFM, it has thus far been seen mostly in children. AFM results in extreme muscle weakness and even paralysis, mainly of the arms and legs. At this time, the leading suspect is a virus that attacks and causes damage to the spinal cord. Unlike polio, which is known to be caused by the poliovirus and for which we have an effective vaccine, the specific cause of AFM is not yet known, and there is no vaccine.

Acute flaccid myelitis is not a new condition, but it has been on the rise in recent years. Due to this steady increase in cases, the Centers for Disease Control and Prevention began tracking the illness in 2014. There have been 570 confirmed cases of the condition since that time, with an average patient age of 5 years. Last year, a total of 233 confirmed cases of AFM occurred in 41 states. This played a role in the CDC’s decision to release an update about the condition in early July, which has put acute flaccid myelitis back into the headlines. The timing of this newest update is due to the observation that AFM has a “season,” with the number of cases spiking in late summer and early fall.

Although cases of AFM are reported each year, outbreaks appear to surge every two years. The CDC reports that so far in 2019, which according to the previous pattern is an “off” year for the condition, 11 cases of acute flaccid myelitis have been reported. However, because awareness of AFM is relatively recent, it’s likely that undiagnosed cases have not made it into the official tallies.

The majority of cases begin with fever and respiratory symptoms similar to a cold or the flu. This is followed by neurological difficulties such as weakness in the arms or legs, a decrease in reflexes, facial weakness, drooping eyelids, difficulty moving the eyes, slurred speech and trouble with swallowing. Occasionally, numbness or pain may be present, and in some cases, patients experience trouble breathing.

A lab test to diagnose the condition has not yet been developed, which makes vigilance by parents and health care providers about potential cases all the more important. Because the later symptoms of the condition can mirror those of other neurological diseases, such as Guillain-Barre syndrome, AFM is difficult to diagnose. There is no known cure, so at this time, treatment focuses on physical and occupational therapy to restore movement.

If your child shows symptoms of AFM, seek medical help immediately. Health care providers whose patients show symptoms of AFM have been directed by the CDC to immediately alert their state or local health departments. They should collect biological specimens to help identify the causes for the condition.