Four years ago, Craig Swanson began feeling a persistent weakness in his body. Doctors eventually discovered he had acute flaccid myelitis (AFM), a rare illness similar to polio, but different enough that the polio vaccine doesn't affect it.

"The (AFM) viruses are genetically pretty similar to polio but different enough that the polio vaccine doesn't prevent them. They cause the same kind of disease in much, much smaller numbers," says Dr. Mark Schleiss, one of Craig's doctors, in an interview with MPR.

The disease isn't a new unknown illness according to Dr. Schleiss. Doctors have known about it and been able to diagnosis it for decades. What is a mystery is the recent uptick in cases. Typically, there have been a handful of cases across the country each year, but this year has seen at least 62, seven of which have been in Minnesota.

Since his diagnosis, Craig has been through hundreds of hours of physical therapy to maintain his mobility. Today, through persistence and determination, Craig is down to two-three sessions a week and inspiring his mother, Larey.