Acute flaccid myelitis: mysterious and serious

Posted by Reeve Staff in Daily Dose on March 05, 2019 # Health, Research

Acute flaccid myelitis (AFM) is a rare but extremely serious disease which begins as a cold and develops into a polio-like flaccid muscle paralysis. Initially, enterovirus D68 was thought to be the cause but recently researchers and doctors say they have not yet been able to make a definite connection between this enterovirus and the polio-like symptoms that sometimes follow the respiratory infection.

Enteroviruses belong to a common family of illnesses that include cold symptoms and rashes as well as polio. Recently, there has been a sharp increase in the number of enterovirus D68 cases and with it, an increasing number of clusters of children sick with breathing problems leading to paralysis associated with the malady known as acute flaccid myelitis.

According to the Centers for Disease Control and Prevention (CDC), the median age of the children impacted by acute flaccid myelitis is about seven, and most patients had a fever and/or a respiratory illness before the neurological symptoms began. The paralysis that sometimes develops is different from transverse myelitis because transverse myelitis usually affects upper motor neurons, resulting in muscle tightness rather than the flaccidity that results from damage to lower motor neurons.

AFM attacks the parts of the spinal cord that control movement thereby paralyzing arms, legs, shoulders, hips and facial muscles. In severe cases, the respiratory system is also affected, making it hard to breathe thus requiring the use of mechanical ventilation. However, sensation and cognitive functioning are unaffected.

There were 127 cases reported in 22 states in 2018 alone as of October, with 62 confirmed as acute flaccid myelitis, according to the CDC. This outbreak marks the third wave of AFM to hit the United States since 2014; this wave is on track to be the worst yet.

In 2014, when AFM first appeared in the U.S, 120 children across 34 states were stricken. Another wave hit in 2016, with 149 patients affected in 39 states.

According to the CDC, AFM cases tend to start in August, peak in October and taper off by December.

While two-thirds of the patients with acute flaccid myelitis have had some improvement in symptoms, one third has not yet improved; one patient has fully recovered.

Treatment is prescribed on a case-by-case basis but usually involves physical and occupational therapy to increase strength and movement in the weakened muscles. Prevention is primarily focused on avoiding colds – washing hands and avoiding contact with others who are sick.

While there is a vaccine for polio, there is not one yet for acute flaccid myelitis because researchers are not yet sure of the source of this devastating disease.

-- by Donna Lowich, Senior Information Specialist

The Christopher & Dana Reeve Foundation Paralysis Resource Center’s Information Specialists can be reached via or by calling 1-800-539-7309.

The National Paralysis Resource Center website is supported by the Administration for Community Living (ACL), U.S. Department of Health and Human Services (HHS) as part of a financial assistance award totaling $8,700,000 with 100 percent funding by ACL/HHS. The contents are those of the author(s) and do not necessarily represent the official views of, nor an endorsement, by ACL/HHS, or the U.S. Government.