Acute Flaccid Myelitis: Neurological Condition Disabling Children

Though rare, acute flaccid myelitis (AFM) is a rapidly progressive and potentially fatal disease that affects the spinal cord, most commonly in young children. Be prepared. Early recognition of the signs and symptoms of AFM may help save your child’s life.

What is AFM?

According to the Centers for Disease Control and Prevention, over 90% of cases of AFM occur in children. AFM, which affects the body’s nervous system, generally develops in children around five-years-of age.

AFM often described as a polio-like illness generally causes muscle weakness and can involve the muscles of respiration. It can be difficult to diagnose as it relies on symptoms, medical history, MRI, other related imaging, and characteristics seen in the evaluation of the spinal cord fluid. Both an acute phase where symptoms begin and a long-term rehabilitation phase generally occur, often leading to long-lasting disability.

Signs and symptoms of AFM

An enterovirus (D68) infection or another viral disease (e.g., West Nile Virus, other enteroviruses, or adenoviruses) generally precedes the onset of AFM. Often, mild respiratory signs and/or fever will occur before weakness, and related clinical symptoms begin. Because the disease negatively affects the motor neurons in the spinal cord (the portion of the body that tells muscles to move, controls breathing, and even allows speaking), symptoms demonstrate problems with motor and movement.

The signs and symptoms vary from common to rare.

Commonly seen symptoms and signs of AFM include sudden onset of:

• Leg or arm weakness
• Loss of muscle tone
• Loss of reflexes

Additionally, patients may experience

• Droopy eyelids
• Trouble moving the eyes
• Facial muscle weakness
• Trouble swallowing or speaking (slurring words)
• Painful arms, legs, back, or neck
• Headache

Uncommonly, trouble passing urine or tingling, even numbness may occur. Some patients may even experience dangerous blood pressure and body temperature changes.

The further concern occurs if the muscles involved in breathing become affected. Trouble breathing can develop, and respiratory failure can occur.

Treatments for AFM

Treatment for AFM remains supportive, as no cure has been identified. Patients will receive supportive care such as steroids and immune modulators or support. Occupational and physical rehabilitation therapy remains key in returning those affected to normal lives as much as feasible. A nerve transfer can be attempted when muscle movement fails to improve (taking a healthy nerve and attaching it to a muscle that stopped working). This procedure may lead to muscle regaining movement over 9-12 months.

Complications from AFM

While some children may recover without incident, most demonstrate muscle weakness for months, even years, after disease onset. Some patients never fully recover and may require lifelong physical and occupational therapy and assistance.

Outbreaks

Health authorities started tracking cases of AFM in 2014 and identified outbreaks in the U.S. in 2016 and 2018. Generally, cases and outbreaks seem most common from August through November. Kids are most commonly exposed to viral and other infections during this time. Though exact causes for outbreaks are not yet well understood.

In the U.S., outbreaks tend to occur every few years and occur alongside increases in cases of common viral diseases seen in kids. This is thought to play a role in the seasonality of AFM.

How to decrease the risk of AFM disabling children

Since we do not know the exact triggers for the disease or understand the full breadth of the course of the illness, it can be difficult to give recommendations on how to prevent the condition or prevent disability.

However, noting when a child has a cold, taking action to ensure a healthy diet and proper nutrition, keeping them isolated when sick, and promptly seeking medical care if AFM is suspected may help minimize debilitating consequences. Ensuring you follow the doctor’s instructions and therapy plans further will help lessen the chance of long-term disability.

What should I know if I have a child with AFM?

Promptly taking action can save your child’s life. Getting your loved one the help they need as soon as you have concerns, noting any of the signs mentioned above, is the best thing you can do for your child.

Make sure you keep track of illnesses and note when your child has a cold or other infection; remember that this disease generally occurs anywhere from a few days to four weeks after a condition causing low-grade fever and respiratory signs.

Can AFM be prevented?

Sadly, AFM can’t be prevented, and we can’t know who will develop it and who won’t. However, protecting your children and yourselves from widespread viral infections and practicing proper hygiene remain key measures to take to protect your children against many diseases.

Routinely clean and disinfect common areas like cooking surfaces and tables. Teach your children to properly cover their noses and mouths when sneezing and coughing.

If you or your child has a fever or other signs of illness, keep them home and prevent exposure to other kids.

Remember, AFM is rare!

Always be vigilant with your children and understand when something is a normal response to a virus and when something should be evaluated. However, remember that AFM is rare! Though first recognized in 2012, there have been only 700 cases in the U.S. since 2014.

So, while AFM may be something to keep in your mind, you don’t have to think it is around every corner each time your child gets a little cold or a fever. Still, knowing the signs and symptoms may help one recognize them early and get the prompt care needed to minimize the chance of long-term complications.