A picornavirus is a virus belonging to the familyPicornaviridae. Picornaviruses are non-enveloped, positive-stranded RNA viruses with an icosahedralcapsid. The genomeRNA is unusual because it has a protein on the 5' end that is used as a primer for transcription by RNA polymerase. The name is derived frompico, meaning small, and RNA, referring to the ribonucleic acid genome, so "picornavirus" literally means small RNA virus.
Picornaviruses are separated into a number of genera and include many important pathogens of humans and animals.[1] The diseases they cause are varied, ranging from acute "common-cold"-like illnesses, to poliomyelitis, to chronic infections in livestock. Additional species not belonging to any of the recognised genera continue to be described.