acute flaccid myelitis

noun

: a serious, rare, neurological condition of sudden onset chiefly affecting young children that causes inflammation of the gray matter of the spinal cord, results in severe, sometimes permanent weakness and loss of muscle tone especially of the arms or legs, and is often preceded by a viral respiratory illness or fever

Note: In addition to the limbs, acute flaccid myelitis may also involve the face, neck, or torso with symptoms including facial droop, slurred speech, difficulty in swallowing, and respiratory failure. While a virus (such as an enterovirus, poliovirus, or flavivirus) is often the cause of acute flaccid myelitis, other causes may include environmental toxins and autoimmune disorders, or the cause may be unknown.

Symptoms associated with acute flaccid myelitis tend to occur about a week after children develop a fever and respiratory illness, causing some to lose the ability to move their face, neck, back, arms or legs. Lauren Sausser
… he appears to have acute flaccid myelitis, a strange and rare paralysis that mainly afflicts children between 4 and 8. Anne Saker
abbreviation AFM

Examples of acute flaccid myelitis in a Sentence

Recent Examples on the Web
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Symptoms of acute flaccid myelitis include limb weakness and paralysis. Faye Chiu, CNN, 23 Sep. 2024 Wastewater samples have detected a significant escalation in an enterovirus called D68, which, in rare cases, has been linked to acute flaccid myelitis, or AFM. Erika Edwards, NBC News, 17 Sep. 2024

Word History

First Known Use

2014, in the meaning defined above

Time Traveler
The first known use of acute flaccid myelitis was in 2014

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Cite this Entry

“Acute flaccid myelitis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/acute%20flaccid%20myelitis. Accessed 24 Mar. 2025.

Medical Definition

acute flaccid myelitis

noun
: a serious, rare, neurological condition of sudden onset chiefly affecting young children that causes inflammation of the gray matter of the spinal cord, results in severe, sometimes permanent weakness and loss of muscle tone especially of the arms or legs, and is often preceded by a viral respiratory illness or fever

Note: In addition to the limbs, acute flaccid myelitis may also involve the face, neck, or torso with symptoms including facial droop, slurred speech, difficulty in swallowing, and respiratory failure. While a virus (as an enterovirus, poliovirus, or flavivirus) is often the cause of acute flaccid myelitis, other causes may include environmental toxins and autoimmune disorders, or the cause may be unknown.

abbreviation AFM
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