In the fall of 2018, all three of Mallory Bradley’s kids became sick. Her sons, aged 8 and 2, ran low fevers for a couple of days, but were soon back to normal, running around their new house in Norfolk, Virginia. Then Ryleigh, Bradley’s 3-year-old daughter, spiked a high fever, and oddly, seemed floppy and unsteady. A kid that usually ran with confidence was suddenly listing and weaving across the playroom — Bradley knew something was wrong.
Since they had just moved, the family didn’t yet have a primary care physician. Bradley’s husband was deployed overseas with the Navy, so on a hot Thursday in September, she loaded all three kids into the van and went to a local children’s emergency room. Doctors there told her not to worry. “The virus just needs to run its course,” she remembers them telling her. They gave Ryleigh some IV fluids and sent her home.
The next morning, Ryleigh still had a fever, but that wasn’t all. “Her eyes were crossed, and she was walking like she was completely drunk,” Bradley said. “She was all over the place swerving.”
The family went back to the E.R. but, she was told not to worry. The balance issues were chalked up to the fever. “My oldest was 8,” Bradley said. “I know I only had eight years of being a mom under my belt, but I had never seen anything like this. I was pretty upset and I told them I was upset, that they weren’t giving me any answers.” Bradley went to a different E.R. that Friday evening, but was again sent home.
On Sunday morning, Ryleigh woke up, smiling, and said she was hungry. Bradley was thrilled at this apparent sign of recovery and proposed they all go out to breakfast. But Ryleigh was struggling to get up and out of bed. Bradley stood her daughter on her feet. “She took two of the strangest steps I’ve ever seen and then she just dropped.”
This time, Bradley wasn’t told to let the virus run its course.
Eventually, Ryleigh was diagnosed with acute flaccid myelitis, or A.F.M., a rare neurological disease that follows an infection with a common virus from the enterovirus family. Most kids get sick with enteroviruses at some point; a tiny fraction go on to develop A.F.M. “Everybody else recovers, but the A.F.M. kid has this horrible catastrophe that affects the rest of their life,” said Emily Erbelding, director of the Division of Microbiology and Infectious Diseases at the National Institutes of Health.
The condition affects the cells of the spinal cord, causing paralysis. Some recovery is possible — at her most affected, Ryleigh could only move her eyes, and today she can walk with assistance, speak and move both arms — but few kids see a full recovery.
A.F.M. is similar to polio, in that both begin with viruses and move on to the nervous system. But the triggering virus in A.F.M. is different, and the upper limbs are often more affected than the lower, while polio often affected the legs. Polio has been eradicated in the United States, thanks to a successful vaccine campaign, and the N.I.H. is in the early stages of researching an A.F.M. vaccine, according to Dr. Erbelding. They are also collecting samples of cerebrospinal fluid, blood, M.R.I. images and other data, both from children who had A.F.M. and their siblings who got the virus but not the sequel, hoping to identify why some kids develop it while most don’t.
The first U.S. cases began in the fall of 2014, and have spiked in the autumns of even-numbered years ever since. The theory is that so many kids get the enterovirus responsible for A.F.M. that the following year hardly anyone lacks an immunity to it. “You have to build up a population of susceptible people,” explained Janell Routh, who leads the A.F.M. program at the Centers for Disease Control and Prevention’s division of Viral Diseases.
If the pattern holds, the fall of 2020 may see more cases emerge — although social distancing for Covid-19 could interrupt transmission of the enterovirus that precedes it. (A.F.M. doesn’t seem related to Covid in any way.) But just in case, experts want parents, caregivers and health care providers to know the signs. Twenty-five percent of children who get A.F.M. will need a ventilator to breathe at some point, and starting physical therapy early can help restore motor function, so getting assistance quickly is vital.
If your children (or the children you care for) seem clumsy or unusually weak, especially after a respiratory infection, “seek emergency department care quickly and press the evaluating physicians to take you seriously,” Dr. Erbelding said. “Take it really, really seriously.”
Dr. Routh echoes that advice. If kids — or adults for that matter, as there are a very few adult cases — exhibit any kind of “floppy weakness,” take them to be seen by a medical professional as soon as you can. “Do not delay. Do not think ‘I am going to wait a couple of days and see if they get better,’” she said.
There is another important thing to know about A.F.M. It is very rare. Although there are probably some cases that were never reported to the C.D.C., the agency has confirmed fewer than 700 cases total since 2014. For comparison, tens of thousands of Americans are getting coronavirus diagnoses every single day.
The year Ryleigh got sick, there were just 238 confirmed cases out of more than 73 million children in the United States. The chances that the sniffles your kid has today will lead to lifelong paralysis are incredibly low. And so the challenge is to file away the information about the symptoms — limb weakness, especially after a viral infection — without adding A.F.M. to the already very long list of things that parents worry about on a daily basis.
Thanks to the pandemic, “stress and anxiety these days are fellow travelers with us,” said Lisa Coyne, a clinical psychologist at Harvard Medical School, who has written about managing anxiety during coronavirus. She suggests trying to avoid ruminating on the incredibly slim possibility that your child will get A.F.M. Remember the symptoms, she said, but don’t be hypervigilant.
If you find yourself mostly interacting with your kids by constantly “checking” on their health, Coyne recommends trying to simply hang out with them instead, which is less stressful and makes them feel loved. If anything is wrong, you’ll notice. “Have a meal together, even if you are standing up. Let them decide what you are going to do, even if it is going to be for 10 minutes,” she advised.
Ryleigh, now 5, is obsessed with unicorns. Since she has spent much of her short life in medical settings — sometimes doing physical therapy for up to 26 hours a week — she would like to be a doctor when she grows up, but preferably a unicorn doctor. She walks with a walker and has gained all her movement back in her left arm; her right arm is a work in progress. Sometimes, to hone fine motor skills during physical therapy sessions, she practices medicine on her dolls, setting up an IV line or applying a tiny cast.
“She is one of the happiest kids you will ever meet,” Bradley said. “The girl keeps a smile on her face. Her determination is out of this world; she never stops.”
Emma Marris writes about science and the environment from Oregon. Her upcoming book, “Wild Souls” is about ethical relationships with the nonhuman world.