Poliomyelitis (Paralytic and Nonparalytic)

Infectious agent: Poliovirus

Description of illness:

Polio is a vaccine-preventable illness caused by the poliovirus that has been eliminated from all but a few countries and is targeted for global eradication. The response to poliovirus infection is highly variable. The majority (up to 72%) of all polio infections in children are asymptomatic. Approximately 24% of polio infections present with a nonspecific, brief flu-like illness. A small portion, 1%–5%, present with meningitis; these symptoms will last from 2 to 10 days, followed by complete recovery. Paralysis affects about 1 in 200 persons with poliovirus infection and 2%-10% patients with paralysis die. Many persons with paralytic poliomyelitis recover completely or partially, although they may develop new muscle pain, weakness or paralysis decades later as adults (post-polio syndrome).