Picornaviridae in the context of "Meningitis"

Poliovirus, the causative agent of polio (also known as poliomyelitis), is a serotype of the species Enterovirus C, in the family of Picornaviridae. There are three poliovirus serotypes, numbered 1, 2, and 3.

Poliovirus is composed of an RNA genome and a protein capsid. The genome is a single-stranded positive-sense RNA (+ssRNA) genome that is about 7500 nucleotides long. The viral particle is about 30 nm in diameter with icosahedral symmetry. Because of its short genome and its simple composition—only a strand of RNA and a nonenveloped icosahedral protein coat encapsulating it—poliovirus is widely regarded as the simplest significant virus.

The rhinovirus (from the Ancient Greek: ῥίς, romanized: rhis "nose", gen ῥινός, romanized: rhinos "of the nose", and the Latin: vīrus) is a positive-sense, single-stranded RNA virus belonging to the genus Enterovirus in the family Picornaviridae. Rhinovirus is the most common viral infectious agent in humans and is the predominant cause of the common cold, causing at least 50% of cold infections.

The three species of rhinovirus (A, B, and C) include at least 165 recognized types that differ according to their surface antigens or genetics. They are among the smallest viruses, with diameters of about 30 nanometers. By comparison, other viruses, such as smallpox and vaccinia, are around ten times larger at about 300 nanometers, while influenza viruses are around 80–120 nm.