1. Basic classification Characteristic Poliovirus Family Picornaviridae Genus Enterovirus Species Enterovirus C Genome ssRNA, positive sense Envelope Absent Capsid Icosahedral Genome size ~7.4 kb Replication Cytoplasm Replication strategy Positive-sense RNA directly functions as mRNA Major receptor CD155/PVR — poliovirus receptor Serotypes PV1, PV2, PV3 Natural host Humans Major transmission Feco-oral Main site of multiplication Oropharynx + intestine Major target in paralyti

Name the viruses included in the Enterovirus group of the family Picornaviridae. Describe in detail the morphology, antigenic properties, pathogenesis, and laboratory diagnosis of poliovirus. (20 marks)(2013) Poliovirus — 20 Marks Essay Introduction Poliovirus is an important member of the genus Enterovirus, family Picornaviridae, and is the causative agent of poliomyelitis. It is an important model virus for studying RNA-virus replication and was one of the first human virus