Risk Assessment: Tools, Techniques, and Their Applications

20.11 Polio Example

Polio is caused by an enterovirus; the least common manifestation of poliomyelitis is paralysis (6). Initially, the affected individual will develop a fever, sore throat, and headache, which will progress to severe back pain and finally progressive muscle weakness. This occurs in approximately 1% of those affected by polio.

There is a 1 in 2.5 million chance that a person will develop polio from the oral polio vaccine. This is increased in an immunocompromised population. Because of the use of the inactivated polio vaccine, this has decreased to zero since 1999. Transmission of enterovirus is through fecal oral route.