Brief History of Polio

¶ … History of Polio

Polio, also known as poliomyelitis, is a contagious viral illness that produces no symptoms in ninety-five percent of cases. While a plague to the human race for centuries, polio was never the devastating scourge that other diseases, such as bubonic plague and smallpox, were. Then, in the early 20th century, polio came into its own, and the largest outbreak of the disease ever seen began. It is from this large outbreak that our dread of polio largely comes from. From this outbreak, we have gotten the devastating images of children in wheelchairs and iron lungs, paralyzed from the ravages of polio, some never to walk again. And it is this outbreak of polio that led to the tremendous push from Western medicine to eradicate it once and for all.

While polio normally produces no symptoms, in the small percentage of cases that do produce symptoms, the disease can take three different forms:

Abortive polio -- Produces mild flu-like symptoms such as diarrhea, sore throat, fever, upper respiratory symptoms, and a general feeling of malaise.

Nonparalytic polio -- Produces neurological symptoms such as neck stiffness and sensitivity to light.

Paralytic polio -- The most devastating form of the disease, and also the least common. Its name says it all. This form of polio causes muscle paralysis, weakening the limbs and even making breathing difficult. This form of polio can kill (Klein, 2005).

While most people with abortive and nonparalytic polio make a full recovery, the prospects for those with paralytic polio are not as good. Though the acute form of the polio illness only lasts about two weeks, the after-effects can be long lasting, even lasting a lifetime. The muscles in the arms and legs that were weakened by the virus may never regain their full strength and can appear withered. Those who do appear to make a full recovery can still come down with post-polio syndrome, in which the damage done to the nerves in the arms and legs causes an acceleration of the natural weakening process that comes with age; sometimes post-polio syndrome may not appear until thirty or forty years after the initial disease has gone.

For those with trouble breathing, an iron lung was the preferred treatment during the height of the 20th century polio epidemic. An iron lung was a machine that literally pushed and pulled the muscles in the chest, manually working the lungs so that they could take in air and exhale it. While many patients only had to be in iron lungs for a little while, a few weeks or months at most, others had to stay in them for years, sometimes for their whole lives. And, while production of new iron lungs ended in the early 1990s, there are still about two hundred iron lungs that still exist ("Iron Lung," 2005). There are also some people in the world who still live inside iron lungs, even today, sometimes having been inside them for decades already.

Polio is contracted from contact with the polio virus. Such contact happens via person-to-person transmission, normally either orally or through contact with contaminated fecal matter. The polio virus invades the gastrointestinal tract of the person it is infecting. The person can then transmit the virus to others through secretions from the nose and mouth during the acute phase of the disease, and then through fecal matter for several weeks after this. Generally, a person's body will produce effective antibodies to the polio virus, thus preventing the virus from leaving the gastro-intestinal tract (Black, 1996). However, in a small number of cases, the virus does penetrate the gastrointestinal tract, and this is when the danger for developing paralytic polio appears.

Because most cases of polio are asymptomatic, the virus can circulate among a population for some time before it is known that there is polio in the community. While those who exhibit no symptoms may not be aware they are infected, they can still carry and transmit the virus to others, who may then develop symptoms themselves. If a person does develop some sort of symptoms, whether paralytic or not, then at least the period of contagion can be estimated; polio is generally most contagious in the ten days before and after symptoms occur. One in ever 200 polio infections results in a case of paralysis, so polio may circulate in the community for some time before it becomes apparent, for in abortive and non-paralytic cases of polio the patient is often presumed to just have the flu. Sadly, polio is usually not recognized as polio until a case of paralysis occurs.

The scourge of polio began to be put to an end in the 1950s with the development of the polio vaccine. Two vaccines were developed: one by Jonas Salk, perhaps the best-known vaccine, was made from an inactive polio virus and administered through injection, and then an oral vaccine was developed by Albert Sabin using a weakened form of the polio virus. Both of these vaccines became widely used as soon as they were developed, since they came right at the height of the polio outbreak of the 20th century. Because of these vaccines, polio has been nearly eradicated from today's industrialized countries. And, because of a push from the World Health Organization, polio is well on its way to being eradicated in other parts of the world.