Molecular model from X-ray diffraction data (PDB ID: 4rhv) of a rhinovirus particle. Rhinoviruses belong to the Picornaviridae family and are composed of a symmetrical protein capsid which contains single stranded RNA at its core. They are the most common cause of the common cold but can also cause sinus and ear infections and exacerbate asthma, cystic fibrosis and chronic bronchitis. Width of image is approximately 29 nm. Digital artwork. Supplied by David S. Goodsell, RCSB Protein Data Bank, courtesy of Wellcome Images.