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Epidemic poliomyelitis, post-poliomyelitis sequelae and the eradication program

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Abstract

Epidemics of paralytic poliomyelitis (polio) first emerged in the late 19th and early 20th centuries in the United States and the Scandinavian countries. They continued through the first half of the 20th century becoming global. A major epidemic occurred in Australia in 1951 but significant outbreaks were reported from the late 1930s to 1954. The poliovirus is an enterovirus that is usually transmitted by the faecal–oral route but only one in about 150 infections results in paralysis when the central nervous system is invaded. The Salk inactivated polio vaccine (IPV) became available in Australia in 1956 and the Sabin live attenuated oral polio vaccine (OPV) was introduced in 1966. After decades of stability, many survivors of the earlier epidemics experience late-onset sequelae including post-polio syndrome. The World Health Organization launched the global polio eradication initiative (GPEI) in 1988 based on the easily administered OPV. The GPEI has resulted in a dramatic decrease in cases of wild polio so that only Pakistan and Afghanistan report such cases in 2020. However, a major challenge to eradication is the reversion of OPV to neurovirulent mutants resulting in circulating vaccine-derived poliovirus (cVDPV). A novel, genetically stabilised OPV has been developed recently to stop the emergence and spread of cVDPV and OPV is being replaced by IPV in immunisation programs worldwide. Eradication of poliomyelitis is near to achievement and the expectation is that poliomyelitis will join smallpox as dreaded epidemic diseases of the past that will be consigned to history.
The author advises that on page 198 of the published article (
Microbiology Australia
, Volume 41, Issue 4, pages 196-200, ), doi:10.1071/MA20053
under the heading Late-onset sequelae of poliomyelitis (LOSP), osteomyelitis should read osteoporosis in the fourth line from the end of the
first paragraph. The correct text is shown here:
A broader category of sequelae, the Late Effects of Polio (LEoP), includes the consequences of musculoskeletal deformities and weakness such as
scoliosis, osteoporosis, joint instability and pain, osteoarthritis and nerve entrapments8.
On the same page, under the heading ‘Global polio eradication initiative’, ‘Paul’ Severs on the fourth line of the first paragraph should read ‘John’
Severs.
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