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​​Acute Flaccid Myelitisis a syndrome characterized by sudden onset of weakness in one or more limbs and distinct abnormalities of the spinal cord gray matter on magnetic resonance imaging (MRI).

AFM was first recognized in August 2014 after a group of children developed acute limb weakness following a respiratory or febrile illness. Almost all of the cases required hospitalization. Some required ventilator support and recovered slowly.


    What causes AFM?

    The cause of this illness remains unknown. Conditions like acute flaccid myelitis can be caused by a variety of germs including several viruses such as: enteroviruses (polio and non-polio), West Nile virus, Japanese encephalitis, Saint Louis encephalitis virus, herpesviruses, and adenoviruses.

    AFM is one of a number of conditions that can result in neurologic illness with limb weakness. Other causes of this neurologic illnesses can, include viral infections, environmental toxins, genetic disorders, and Guillain-Barre syndrome, a neurologic disorder caused by an abnormal immune response that attacks the body’s nerves. However, despite extensive laboratory testing, the cause for AFM is difficult to identify.

    How is AFM Spread?

    Currently the mode of transmission is unknown. This would depend on the agent causing AFM. Transmission could be through respiratory secretions such as with adenovirus or through the fecal/oral route such as with poliomyelitis or other enteroviruses.

    Who is most at risk for AFM?

    Anyone can get AFM or neurologic conditions like it, although many of the AFM patients were children. The illness typically manifest as sudden onset of asymmetrical limb weakness, loss of muscle tone and reflexes. Additional signs and symptoms may vary, although the most severe symptom is respiratory failure. Recovery from AFM can be prolonged. Currently, no deaths have been reported due to AFM, although patients with serious preexisting conditions have expired after AFM onset.

    What can I do to protect myself from AFM?

    Even though the specific etiology of AFM is uncertain, the following interventions are good measures to prevent AFM:

    1. Ensure up to date vaccinations on all recommended vaccines, particularly the polio vaccine.
    2. Minimize risk of mosquito-borne illnesses by using repellant when in high risk areas, and eliminate stagnant and standing water near housing.
    3. Wash hands to stop the spread of germs. Use proper hand hygiene and wash hands frequently.

    For more information visit the CDC AFM Page.

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Data image linking to CDC