Scientists at the University of Maryland, Baltimore County, have uncovered a crucial trick used by enteroviruses—the group behind diseases like polio, myocarditis, encephalitis, and even the common cold—to reproduce inside human cells. The team captured, in unprecedented detail, how viral RNA recruits both viral and human proteins to assemble the machinery needed for replication, acting almost like a molecular “on-off switch” that controls whether the virus copies itself or makes proteins.