Polio (poliomyelitis or infantile paralysis) is a viral infection that was common in the Western world until the early 1960s.
Most cases of polio developed only mild symptoms while others were more severe and progressed to a paralytic form.
In Australia there were major polio epidemics in the late 1930s, early 1940s and 1950s. The last epidemic was in 1956.
Polio vaccines were introduced in Australia in 1956 (Salk) and 1966 (Sabin) and were followed by mass immunisation programs. With the continuing immunisation of children, the disease will be eradicated in Australia as well as in other parts of the Western world. It is estimated that a minimum of 20,000 – 40,000 people had paralytic polio in Australia between 1930s and 1960s. Actual figures for the number of people infected with the virus are up to a hundred times greater, 2 – 4 million Australians.
While polio no longer threatens Australian society today, it is not forgotten. Thousands of Australians are now experiencing what is known as the late effects of polio or post-polio syndrome (PPS).
The late effects of polio are a set of unexpected new symptoms occurring some 30 – 40 years after the initial infection.
The late effects of polio are generally considered to be a second phase of polio. Some people will develop symptoms while others will not.
Only people who previously had polio can experience the late effects of polio, although its symptoms may be synonymous with other conditions.
Commonly reported symptoms include unaccustomed fatigue (either muscle fatigue or a feeling of total exhaustion); new muscle weakness (including muscles apparently unaffected at the time of the initial polio infection); joint and/or muscle pain; sleeping, breathing or swallowing difficulties, increased sensitivity to cold temperatures; and a decline in the ability to
perform basic daily activities.
The cause of these symptoms is as yet unknown, but research suggests there are a number of possibilities of which the “overuse of polio-weakened muscles” is the most common theory.
The overuse theory suggests that post-polio muscles need to work harder than other muscles not affected by the virus to keep up with the demands of everyday living
There is no definitive test for PPS. A doctor diagnoses PPS by eliminating other possible causes of the person’s symptoms. Referral to a specialist in Rehabilitation Medicine is desirable.
Early detection of symptoms can help to alleviate ensuing problems and prevent further deterioration attributable to overuse.
Energy conservation and pacing of activities appear to be quite successful in managing the symptoms of the late effects of polio.
During the 1990s research into the late effects of polio and PPS was undertaken at Sydney’s Prince of Wales Medical Research Institute.