Poliovirus Type 1 is a human enterovirus and member of the family of Picornaviridae. The virus infects humans in two different ways, the infection is either a mild illness without serious symptoms, or the virus infects the central nervous system and may cause paralysis.
The virus is most often spread by the faecal-oral route. Poliovirus enters through the mouth and multiplies in the intestine. Infected individuals shed poliovirus into the environment for several weeks, where it can spread rapidly through a community, especially in areas of poor sanitation.
Minor infections include mild symptoms, including:fever, headache, and sore throat. However, paralytic disease occurs when the virus enters the central nervous system and replicates in motor neurons within the spinal cord, brain stem, or motor cortex, resulting in the selective destruction of motor neurons leading to temporary or permanent paralysis.