Enteroviruses and Rhinoviruses

The enteroviruses and rhinoviruses are two large groups of viruses belonging to the Picornaviridae that regularly cause infections in humans. Like all picornaviruses they are small nonenveloped viruses with a single-stranded, positive sense RNA genome that contains a single open reading frame encoding a polyprotein that undergoes autocatalytic cleavage to give virus structural proteins and replication enzymes. The human enteroviruses consist of 66 serotypes (1 ) that include the polioviruses, group A and B coxsackieviruses, and echoviruses. More recently identified serotypes have been numerically classified as enterovirus serotypes 68–71 (some serotypes have been reclassified, hence the missing serotype numbers), while the rhinoviruses consist of over 100 distinct serotypes (2 ).