#14,176
Acute flaccid myelitis (AFM) is a rare illness that affects the nervous system - and is most commonly reported in small children. AFM is a subset of conditions that fall under a broader `umbrella' of syndromes called Acute Flaccid paralysis (AFP), which may include myelitis, peripheral neuropathy, myopathy, Guillain-Barré syndrome (GBS), toxic neuropathy, and other muscle disorders.
While the exact causes of Acute flaccid myelitis aren't fully understood, it has been linked to a number of viral infections, including West Nile Virus, Adenoviruses, and a number of (polio and non-polio) enteroviruses, including EV-71 and more recently, EV-D68.Five years ago, in the early fall of 2014, we saw a nationwide outbreak of EV-D68 (49 states), producing a wide range of illness, including severe respiratory distress, resulting in the hospitalization of hundreds of children (see CDC HAN Advisory On EV-D68).
At the same time, doctors around the country reported a concurrent spike in polio-like paralysis in children (e.g. AFP or AFM (Acute Flaccid Myelitis)) often following a viral illness.Every two years since then (fall of 2016 and 2018) we've seen an increase in AFM cases (see chart below), with the largest wave (n=233) reported last fall. The CDC has confirmed 570 cases since they began tracking AFM in August of 2014.
While this biannual pattern might suggest this fall could be an `off' season for AFM, we don't know enough about this disease - and why it seems to skip a year - to make that sort of assumption.
Since early detection and treatment are essential - both for the best patient outcome and to aid in the search for the cause of these outbreaks - the CDC has devoted this month's Vital Signs Report to recognizing the symptoms of AFM, targeting both parents and clinicians.Yesterday the CDC held a Vital Signs telebriefing, released an early MMWR on AFM Surveillance, published two short videos (see below), updated several of their AFM webpages, issued a press release, and published their July Vitals Signs report on AFM.
You'll find links and some highlights from this massive rollout below. There is obviously too much to cover more than the gist in this blog, so click through for details.
First stop, two short (1 minute) videos on recognizing the signs and symptoms of AFM.
Next link and some excerpts from the CDC Press Release:
CDC Urges Doctors to Rapidly Recognize and Report AFM Cases
Intense effort underway to understand and prevent this serious neurologic syndrome
Español (Spanish)
Press Release
Embargoed Until: Tuesday, July 9, 2019, 1:00 p.m. ET
Contact: Media Relations
(404) 639-3286
As the late summer/early fall “season” for acute flaccid myelitis (AFM) nears, CDC is calling on medical professionals to quickly recognize AFM symptoms and report all suspected cases to their health department. Early recognition and reporting are critical for providing patients with appropriate care and rehabilitation, and better understanding AFM, according to a new Vital Signs report.
The majority of AFM patients are previously healthy children who had respiratory symptoms or fever consistent with a viral infection less than a week before they experienced limb weakness. Since AFM can progress quickly from limb weakness to respiratory failure requiring urgent medical intervention, rapidly identifying symptoms and hospitalizing patients are important.
Dr. Robert Redfield, CDC Director
“CDC continues to pursue the definitive cause and mechanisms that define this disease and we sincerely appreciate the important contributions of the AFM Task Force in helping us get closer to critical answers,” said CDC Director Robert Redfield, M.D. “I urge physicians to look for symptoms and report suspected cases so that we can accelerate efforts to address this serious illness.”
Late summer and early fall is AFM “season”
CDC began tracking AFM in 2014, when the first outbreak of 120 cases occurred. Another outbreak occurred in 2016 with 149 cases, and again with 233 patients in 41 states in 2018– the largest outbreak so far. AFM cases have so far followed a seasonal and biennial pattern, spiking between August and October every other year.
In an analysis of cases confirmed in 2018, CDC detected enteroviruses and rhinoviruses in nearly half of respiratory and stool specimens. Of the 74 cases with a cerebral spinal fluid specimen, only two were positive for enteroviruses (EV-A71 and EV-D68). CDC and other scientists continue to investigate how enteroviruses, including EV-D68, might initiate AFM. All specimens tested negative for poliovirus, a related enterovirus that can cause AFM.
(Continue . . . .)
The summary from the early release MMWR on AFM surveillance follows:
Vital Signs: Surveillance for Acute Flaccid Myelitis — United States, 2018
Early Release / July 9, 2019 / 68
Adriana Lopez, MHS1; Adria Lee, MPH1; Angela Guo, MPH1; Jennifer L. Konopka-Anstadt, PhD1; Amie Nisler, MPH1; Shannon L. Rogers, MS1; Brian Emery1; W. Allan Nix1; Steven Oberste, PhD1; Janell Routh, MD1; Manisha Patel, MD1 (View author affiliations) View suggested citation
Summary
What is already known about this topic?
Biennial U.S. outbreaks of acute flaccid myelitis (AFM) have been recognized since 2014. Most cases occur in children during late summer and early fall.
What is added by this report?
During 2018, 233 confirmed AFM cases were reported, the largest number since surveillance began in 2014. Upper limb involvement only was more prevalent in confirmed cases (42%), as was report of respiratory symptoms or fever (92%) within 4 weeks preceding limb weakness onset. Median intervals from onset of limb weakness to hospitalization, magnetic resonance imaging, and reporting to CDC were 1, 2, and 18 days, respectively.
What are the implications for public health practice?
Prompt recognition, early specimen collection, and rapid reporting will expedite public health investigations and help characterize AFM.
(Continue . . . )
Next, the CDC July AFM Vital Signs report itself. You'll want to click through for the full report, which includes copious links to other resources.
Overview
Acute flaccid myelitis (AFM) is a rare but serious syndrome (a pattern of symptoms) 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.
Issue Details
Related Pages and Resources
- Vital Signs: Press Release — CDC Urges Doctors to Rapidly Recognize and Report AFM Cases [English]
- Vital Signs: Press Release — Los CDC instan a los médicos a reconocer y notificar rápidamente los casos de mielitis flácida aguda [Spanish]
- Vital Signs: Surveillance for Acute Flaccid Myelitis — United States, 2018
- AFM Investigation
- For Clinicians and Health Departments
- Specimens to collect and send to CDC
- Job aid on how to send information to the health department about a patient under investigation (PUI) for AFM pdf icon[444 KB, 2 pages]
Science Behind the Issue
And lastly, the CDC summarizes where we are today, and The Way Forward:
CDC Is:Clinicians Can:
- Monitoring AFM trends and the clinical presentation.
- Researching possible risk factors.
- Conducting advanced lab testing and research to understand how viral infections may lead to AFM.
- Tracking long-term patient outcomes.
Health Departments Can:
- Contact neurologists specializing in AFM through the AFM Physician Consult and Support Portal for help with patient diagnosis and medical management. https://bit.ly/2Y2U3VRexternal icon
- Contact CDC with any questions about AFM, including how to report cases and collect appropriate specimens.
Parents Can:
- Work with CDC to collect medical information, MRI images, and specimens, and classify cases.
- Communicate information about AFM to clinicians and the public.
- Immediately seek medical care if their child develops sudden arm or leg weakness.
