TOPICS: Poliovirus, RNA virus, positive sense, enterovirus, picornavirus, icosahedral, naked virus, capsid, cleaved, functional proteins, Salk vaccine, killed vaccine, Sabin vaccine, live vaccine, internal ribosomal entry site, IRES, endocytosis, intestines, bloodstream, CNS, central nervous system, meningitis, anterior horns, spinal cord, fasciculations, flaccid paralysis, muscle atrophy, respiratory failure, fever, vomiting, linear virus, fecal-oral transmission