Picornaviruses (pico-RNA-viruses) are non-enveloped, positive stranded RNA viruses with an icosahedral capsule. Their positive, single stranded RNA architecture places them in Baltimore group IV. The name derives from the fact that they are small (pico) RNA viruses.
The picornavirus family contains a number of genera, most of which do no affect humans. The largest genus is enterovirus and includes enterovirus 71, poliovirus, enterovirus 71, coxsackievirus and rhinovirus).
Infection with picornviruses can result in symptoms that range from nasal inflammation to flaccid paralysis and death.