Enterovirus

Human rhinoviruses (HRVs) and enteroviruses (HEVs) belong to the Picornaviridae family and are prominent causes of respiratory disease. They share identical genomic organization and high sequence homology. Their genome is divided into three sections: a 5’untranslated region (5’UTR), an open reading frame of the polyprotein that codes for all four capsid proteins (VP1-4) and the non-structural genes, and a 3’untranslated region. Enteroviruses are members of the picornavirus family, a large and diverse group of small RNA viruses. According to the present classification, the enterovirus genus comprises the following species: poliovirus, human enterovirus A (HEV-A) (coxackie A viruses and enterovirus 71), HEV-B (coxsackie B viruses, echoviruses, coxsackie A9 virus, and enteroviruses 69 and 73), HEV-C (coxsackie A viruses), HEV-D (enteroviruses 68 and 70), and at least three animal enterovirus species (bovine, simian, and porcine enteroviruses). They all contain a genome of approximately 7,500 bases and positive [(+)]-strand polarity. After infection of the host cell, the genome is translated in a cap-independent manner into a single polyprotein, which is subsequently processed by virus-encoded proteases into the structural capsid proteins and the nonstructural proteins, which are mainly involved in the replication of the virus.