Poliomyelitis

Poliomyelitis

Poliovirus

3 serotypes (123), 30 nm icosahedral, no envelope, postive single strand RNA genome, (+ssRNA), fast replication 10k-100k virion/cells in 6-8 hrs

Humans

Digestive Tract

Fecal-oral route

7-21 days

virus infects throat and intestinal mucosa and can spread through the lymphatic system and blood stream to other tissues including the CNS. Lysis of infected motor neurons during viral release results in paralytic muscle atrophy

70% asymptomatic; 24% experience non specific illness- low fever, sore throat; 1-5% experience meningitis- stiffness and/or pain in neck, back, or legs, headache, vomitng; <1% experience paralysis

Parayltic Polio- 2/3 of paralytic cases invole permanet paralysis, mortality, post-polio syndrome- increased muscle pain and weakness years later

Vaccination- Inactivated poliovirus or attenuated poliovirus; effective sanitation, avoid contaminated water (public pools)

Supportive care