Picornaviridae (family)
Enterovirus (genus)
– Most often infect
children
– Most cases are
asymptomatic, particularly when infection is limited to the pharynx and gastrointestinal tract.
- In approximately 5% of cases, nonspecific flu-like symptoms occur and subside within a week.
- However, 1 in 200 cases will involve the central nervous system.
– Virus reaches the CNS via
viremia and retrograde neuronal travel
– Replicates in the
spinal cord (motor neurons of the anterior horn).
– Causes meningitis in some individuals
–
Poliomyelitis occurs in 1 out of 200 poliovirus infections:
Temporary or permanent paralysis that typically involves the limbs; when the muscles involving respiration are involved, infection can be fatal.
- “Iron lung” = Emerson Respirator used to mechanically support respiration in polio patients.
- Post-polio syndrome occurs when nerve dysfunction occurs 30-40 years after initial poliomyelitis.
- Vaccination can prevent this crippling and potentially fatal disease.
– The
inactivated polio vaccine (IPV) is currently given to children in the United States and to adults at increased risk (travelers, laboratory and health care workers, etc.).
– The
live attenuated oral polio vaccine (OPV) is still available in some countries.
Image Credit:
“Public Domain Picture | This Photograph Shows the Rear Oblique View of an Emerson Respirator, Known as an ‘iron Lung.’ Devices Such as These Were Used by Polio Pati | ID: 13519566018407 | PublicDomainFiles.Com.” Accessed July 30, 2018. http://www.publicdomainfiles.com/show_file.php?id=13519566018407.
