Timing Key to Rapidly Recognizing and Reporting Acute Flaccid Myelitis Cases

Three National Outbreaks of AFM Since 2014

September 11, 2019

Acute flaccid myelitis (AFM) is a rare but serious syndrome that causes limb weakness, mostly in children. Three national outbreaks have occurred starting in 2014, when CDC began surveillance for AFM.

  • Most patients developed AFM in late summer or early fall.
  • Most patients had respiratory symptoms or fever consistent with a viral infection less than a week before onset of limb weakness.

CDC believes viruses, including enteroviruses, play a role in AFM. Currently, there are no proven ways to treat or prevent AFM.

Prompt symptom recognition, specimen collection, and reporting to CDC are all critical to improve understanding of this complex syndrome, including its risk factors, outcomes, possible treatments, and ways to prevent it. AFM is rare, and there is no lab test available yet to diagnose patients.

What Clinicians Can Do

  • Strongly suspect AFM in patients with acute flaccid limb weakness, especially after respiratory illness or fever, and between August and October.
  • Hospitalize patients immediately, collect lab specimens, diagnose, and begin medical management.
    • Don’t wait for CDC’s case classification for diagnosis.
  • When clinicians recognize AFM early, they can quickly—
    • Get patients the best care, including treatment and rehabilitation.
    • Collect lab specimens like blood or urine to increase understanding of AFM and its causes.
    • Report suspected cases for prompt investigation and outbreak detection.
  • Alert the appropriate health department and send lab specimens and medical records.
  • Contact neurologists specializing in AFM through the AFM Physician Consult and Support Portal for help with patient diagnosis and medical management.
  • Contact CDC with any questions about AFM, including how to report cases and collect appropriate specimens.

What Health Departments Can Do

  • Work with CDC to collect medical information, MRI images, and specimens, and classify cases.
  • Communicate information about AFM to clinicians and the public.

What the CDC is Doing

  • Monitoring AFM trends and clinical presentation.
  • Researching possible risk factors.
  • Conducting advanced laboratory testing and research to understand how viral infections may lead to AFM.
  • Tracking long-term patient outcomes.

You can find more information about AFM from CDC in Vital Signs or call 1-800-CDC-INFO (232-4636) TTY: 1-888-232-6348.

More Resources
What is AFM?
CDC Vital Signs: Acute Flaccid Myelitis