Two years ago, Christa Bottomley’s healthy 5-year-old son caught a viral cold like the rest of the family. Everyone else recovered, but in his case the virus triggered a neurological condition.

The condition is called acute flaccid myelitis, or AFM. Though rare, it has jumped onto the national radar. As doctors struggle to explain its third nationwide peak since 2014, families like the Bottomleys are trying to provide hope to others hit with the sudden, polio-like disease and to push for more awareness in the medical community.

AFM causes inflammation of the nervous system, particularly the gray matter of the spinal cord, which results in weakening muscles in usually one or more arms and legs. It can also affect the face and lead to difficulty swallowing or even breathing. Almost all AFM patients are hospitalized for several days or even months.

It affects mainly children, who sometimes recover over time, often with therapy. Others remain paralyzed, needing long-term care and rehabilitation.

Sebastian was in a hospital in Hershey, Pa., for three weeks and lost movement in both arms and legs. He couldn’t sit up or turn his head in one direction. He spent another 60 days at Kennedy Krieger pediatric hospital in Baltimore, but still couldn’t move his right arm or either leg.