"Rhinovirus (from the Greek rhin- which means "nose") was a genus of the Picornaviridae family of viruses. It has been now merged into Enteroviruses, a group of Picornaviridae that includes Poliovirus, Coxsackie A virus, and Hepatitis A. Rhinoviruses are the most common viral infective agents in humans, and a causative agent of the common cold. It is lytic in nature. Rhinoviruses have single-stranded positive sense RNA genomes of between 7.2 and 8.5 kb in length. At the 5' end of the genome is a virus-encoded protein, and like mammalian mRNA, there is a 3' poly-A tail. Structural proteins are encoded in the 5' region of the genome and non structural at the end. This is the same for all picornaviruses. The viral particles themselves are not enveloped and are icosahedral in structure."