Acute Flaccid Myelitis: Symptoms, Causes, and Treatment Health ConditionsFeaturedBreast CancerIBD MigraineMultiple Sclerosis (MS)Rheumatoid ArthritisType 2 DiabetesSponsored TopicsArticlesAcid RefluxADHDAllergiesAlzheimer's & DementiaBipolar DisorderCancerCrohn's DiseaseChronic PainCold & FluCOPDDepressionFibromyalgiaHeart DiseaseHigh CholesterolHIVHypertensionIPFOsteoarthritisPsoriasisSkin Disorders and CareSTDsDiscoverWellness TopicsNutritionFitnessSkin CareSexual HealthWomen's HealthMental HealthSleepOriginal SeriesFresh Food FastDiagnosis DiariesYou’re Not AlonePresent TenseVideo SeriesYouth in FocusHealthy HarvestNo More SilenceFuture of HealthPlanHealth ChallengesMindful EatingSugar SavvyMove Your BodyGut HealthMood FoodsAlign Your SpineFind CarePrimary CareMental HealthOB-GYNDermatologistsNeurologistsCardiologistsOrthopedistsLifestyle QuizzesWeight ManagementAm I Depressed? A Quiz for TeensAre You a Workaholic?How Well Do You Sleep?Tools & ResourcesHealth NewsFind a DietFind Healthy SnacksDrugs A-ZHealth A-ZConnectFind Your Bezzy CommunityBreast CancerInflammatory Bowel DiseasePsoriatic ArthritisMigraineMultiple SclerosisPsoriasisFollow us on social mediaShopProducts by ConditionInsomniaStress ReliefBack PainNeck PainSleep ApneaHot SleepersAllergiesPain ReliefProduct ReviewsVitamins & SupplementsSleepMental HealthNutritionAt-Home TestingCBDMen’s HealthWomen’s HealthHealth ConditionsDiscoverPlanConnectShopSubscribe

About Acute Flaccid Myelitis

Medically reviewed by Heidi Moawad, M.D. — By Jill Seladi-Schulman, Ph.D. on September 16, 2022Acute flaccid myelitis (AFM) is a rare neurological condition that can cause paralysis. It mainly occurs in children, but it can occur in adults, too. As of writing, the Centers for Disease Control and Prevention (CDC) reports that there have been 13 confirmed cases of AFM in 2022. A total of 692 cases have been reported since the CDC began tracking the condition in 2014. Below, we’ll go into more detail about AFM, including its symptoms and causes, as well as how doctors diagnose and treat it.

What is acute flaccid myelitis

AFM is a rare neurological condition that impacts the nervous system. The most common symptom of AFM is limb weakness or paralysis that comes on suddenly. People with AFM have areas of damage in the gray matter of the spinal cord that doctors can see using an MRI. The gray matter is important for things like muscle movement and gathering sensory information. The damage that occurs due to AFM can be permanent and life threatening. This makes AFM a medical emergency. According to the CDC, 98% of people with AFM get hospital admittance, and 54% go to the intensive care unit (ICU).

Symptoms of acute flaccid myelitis

Many people who develop AFM have an illness with fever about 1 to 10 days before any symptom onset. In addition to fever, other early symptoms can include a runny or stuffy nose, cough, or sore throat. When the symptoms of AFM develop, they can include:limb weakness or paralysis that comes on suddenlyloss of reflexespain in the limbs, neck, or backdifficulty with movementfacial weakness, which can cause drooping eyelids or difficulty moving the eyesdifficulty talking or swallowing Fever and headache are also common symptoms of AFM. AFM is a medical emergency. If you or a child experiences any of the symptoms above, call 911 or go to the emergency room immediately.

Causes of acute flaccid myelitis

The exact cause of AFM is still unknown. However, an increase in the occurrence of AFM often links to a rise in illnesses due to the enterovirus EV-D68, which can cause a cold-like illness. Indeed, many people who develop AFM report having an illness with fever before their symptoms come on. Most cases of AFM happen between August and November, a time of the year when many enteroviruses like EV-D68 circulate. Enteroviruses are a diverse group of viruses. Several types of enteroviruses can cause the common cold, while others cause hand, foot, and mouth disease and polio. We don’t know how exactly EV-D68 may cause AFM. It’s possible that the damage in the gray matter, which leads to the symptoms of AFM, could be due to the virus itself, the immune system’s response to the infection, or both. Many people that get AFM are children. A 2020 research review noted that the average age at diagnosis is 6.3 years old. Less than 15% of people who develop AFM are adults.

Is AFM related to polio

Polio and AFM cause very similar symptoms. Additionally, EV-D68 and poliovirus are both enteroviruses. However, experts have not detected poliovirus in samples from people with AFM. According to the CDC, experts adopted the term “AFM” in 2014. It refers to a polio-like illness that has an unknown cause. Since the introduction of the polio vaccine, experts effectively eliminated polio in the United States. In rare cases, travelers who’ve contracted it have brought it into the country.

Diagnosis for acute flaccid myelitis

The diagnosis of AFM can be tricky. Not only is it rare overall, but its symptoms can be similar to other neurological conditions, including, but not limited to:polioGuillain-Barre syndrometransverse myelitismultiple sclerosisacute disseminated encephalomyelitis Getting a thorough medical history is important. In addition to evaluating your symptoms, a doctor will note things like age, time of year, and if you have a recent history of illness with fever. They can also do the following tests to help confirm a diagnosis of AFM:Physical exam: During this exam, your doctor will look for areas with reduced muscle tone and weakness. They’ll also check your reflexes.MRI scan: An MRI scan uses radio waves and strong magnets to create images of the inside of your body. Doctors can use it to look for signs of damage in your spinal cord.Cerebrospinal fluid analysis: This test uses a sample of cerebrospinal fluid that a doctor collects using a lumbar puncture. It can help your doctor to look for signs of inflammation in your spinal cord.Nerve conduction tests: These tests help check the signaling along your nerves. They can help a doctor figure out where along your nerves the weakness or paralysis starts.Laboratory tests: Additional laboratory tests of blood, stool, or respiratory samples can aid your doctor in confirming or ruling out other health conditions as the causes of your symptoms.

Treatment for acute flaccid myelitis

There’s currently no standard treatment for AFM. Further, according to a 2020 research review, only observational studies on treatment outcomes for AFM are currently available. Experts need to perform further research to find effective treatments for the condition. Right now, the treatment of AFM focuses on providing supportive care, such as:monitoring vital signs like respiratory rate, heart rate, and blood pressuremanaging painstabilizing respiratory, heart, and bowel functionproviding respiratory support with a ventilator, if necessarypreventing complications from being immobile, such as bed sores and blood clots It’s also possible that your doctor may choose to use other types of treatments as well, such as:intravenous immunoglobulincorticosteroidsplasmapheresis These treatments can help suppress the immune system to reduce an immune response that could be a factor in an underlying condition. However, according to CDC guidance, there’s currently no evidence for or against the use of these treatments for AFM.

Preventing acute flaccid myelitis

Since experts don’t yet know the exact cause of AFM, there’s currently no way to prevent it completely. It’s unclear why some people develop AFM and others do not. However, since AFM links with a viral infection, there are some general steps that you can take to help reduce your risk, such as:washing your hands frequently with soap and waterrefraining from touching your eyes, mouth, or nose with unwashed handscleaning frequently touched surfaces in your home regularly, such as doorknobs and light switchesavoiding close physical contact with people who are sick

Outlook for acute flaccid myelitis

AFM can lead to permanent muscle weakness or paralysis. Although the outlook can vary by individual, generally speaking, a full recovery is uncommon. For example, a small 2015 study involved a follow-up with 45 people who had experienced AFM. During an average follow-up of 9 months, 38% reported persistent limb weakness. A small 2017 study involved a follow-up with 8 children a year after they had developed AFM. Although experts observed some improvements over time, 6 children had continuing problems with movement a year later. Whether or not experts detect enterovirus in samples may also affect the outlook, according to a small 2020 study. Compared with patients who tested negative for enterovirus, those who tested positive had a higher likelihood of:admission to the ICUweakness or paralysis affecting all four limbsbulbar palsy, which can cause symptoms like trouble breathing and difficulty swallowing or speakingproblems with bowel or bladder functioncardiovascular instability, which can include atypical heart rate or blood pressure Doctors will likely recommend physical therapy, occupational therapy, or both if you’ve had AFM. Physical therapy focuses on improving strength and flexibility, while occupational therapy helps you to learn ways to do daily activities.

The bottom line

AFM is a rare neurological condition that can lead to permanent muscle weakness or paralysis. It mainly affects children, but adults can develop the condition as well. Experts generally believe that a viral infection may trigger AFM, specifically with the enterovirus EV-D68. However, why some people develop AFM while others do not is currently unclear. AFM is a medical emergency. If you or a child experiences limb weakness or paralysis that comes on suddenly, get emergency medical care. Last medically reviewed on September 16, 2022

How we vetted this article

SourcesHistoryHealthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. We avoid using tertiary references. You can learn more about how we ensure our content is accurate and current by reading our editorial policy.Acute flaccid myelitis (AFM). (2022).
cdc.gov/acute-flaccid-myelitis/index.htmlFang X, et al. (2020). Acute flaccid myelitis: Current status and diagnostic challenges.
ncbi.nlm.nih.gov/pmc/articles/PMC7354978/Fatemi Y, et al. (2019). Acute flaccid myelitis: A clinical overview for 2019.
mayoclinicproceedings.org/article/S0025-6196(19)30274-5/fulltextGlobal immunization division. (2022).
cdc.gov/globalhealth/immunization/Martin JA, et al. (2017). Outcomes of Colorado children with acute flaccid myelitis at 1 year.
ncbi.nlm.nih.gov/pmc/articles/PMC5501931/Murphy OC, et al. (2020). Acute flaccid myelitis: Cause, diagnosis, and management.
ncbi.nlm.nih.gov/pmc/articles/PMC7909727/Non-polio enterovirus. (2020).
cdc.gov/non-polio-enterovirus/index.htmlVan Haren K, et al. (2015). Acute flaccid myelitis of unknown etiology in California, 2012-2015.
jamanetwork.com/journals/jama/fullarticle/2478202Vital signs. (2022).
cdc.gov/vitalsigns/index.htmlYea C, et al. (2020). Association of outcomes in acute flaccid myelitis with identification of enterovirus at presentation: A Canadian, nationwide, longitudinal study.
linkinghub.elsevier.com/retrieve/pii/S2352-4642(20)30176-0Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available. Current Version Sep 16, 2022 By Jill Seladi-Schulman, PhD Edited By Rosalie Rung Medically Reviewed By Heidi Moawad, MD Copy Edited By Sofia Santamarina Share this articleMedically reviewed by Heidi Moawad, M.D. — By Jill Seladi-Schulman, Ph.D. on September 16, 2022

Read this next

What You Need to Know About Post-Polio SyndromeMedically reviewed by Heidi Moawad, M.D. People who survived polio may experience symptoms decades later. Learn about this syndrome and how to manage it.READ MOREWhat to Know About the IPV (Polio) VaccineMedically reviewed by Alana Biggers, M.D., MPH IPV stands for inactivated polio vaccine. It is a safe and effective vaccine that must be given in a series of four shots to boost protection against…READ MOREWhat Are Schmorl’s Nodes, and Should I Be Concerned About Them?Medically reviewed by Angelica Balingit, MD Learn how these lesions on your spine may affect you and how to treat them.READ MOREDoes Fascia Blasting Work and Is It Safe?Medically reviewed by Daniel Bubnis, M.S., NASM-CPT, NASE Level II-CSS Fascia blasting has become a popular technique for loosening the fascia and treating conditions like pain and cellulite. But does it work and what are…READ MOREBiceps Tendinitis: Treatment, Testing, and TapingMedically reviewed by Angela M. Bell, MD, FACP Biceps tendinitis is a painful condition, but it can be treated, and sometimes taping helps. Here's what you need to know about finding relief.READ MOREBiceps Tendinitis: What Is It and What to Do About ItMedically reviewed by Daniel Bubnis, M.S., NASM-CPT, NASE Level II-CSS Bicep tendonitis is common from everyday wear and tear on your joints. It can often be addressed with rest. Let's discuss the details.READ MOREPaget’s Disease: What Causes This Chronic Bone Disorder?Medically reviewed by Avi Varma, MD, MPH, AAHIVS, FAAFP Paget’s disease of the bone is a chronic condition that progresses slowly over time. But Paget’s disease of the bone is treatable with medication.READ MOREAnterior tibiotalar ligamentMedically reviewed by the Healthline Medical Network The anterior inferior ligament and the anterior ligament of the lateral malleolus are also known as the anterior tibiotalar ligament. It is located in…READ MORE*clone Market VIP* The 11 Best Mattresses for Lower Back Pain in 2022Medically reviewed by Gregory Minnis, DPT These 11 picks are some of the best mattresses for lower back pain. Offering medium-firm support, they’ll help keep you aligned and rested.READ MORE