So researchers tried a new trick: They checked patients' spinal fluid for signs the immune system had fought an invading virus. The problem: Doctors seldom found those viruses in the patients' spinal fluid, leaving doubt about the link. Antibodies programmed to track specific germs only wind up in spinal fluid if they fought infection there — what Wilson's team set out to find. Add some spinal fluid, and any antibodies present would stick to their target, able to be identified. In tests of spinal fluid from 42 AFM patients and 58 children with unrelated neurologic illnesses, only enterovirus-targeting antibodies emerged as the potential culprit.

Source: ABC News October 21, 2019 15:33 UTC