~~~ Some Good News About a Bad Bug ~~~

Through an exhaustive effort of personnel associated with the Central and South American regions of the World Health Organization to immunize every single child within these regions (the US and Canada have been doing this for many years), polio appears to have disappeared from North, Central, and, South America - all of the Americas! A recent report from the World Health Organization, stated that not one single new case of polio had occurred in the Americas for the past three years. Officials are very hopeful that all of the members of the terrible paralysis-causing poliomyelitis virus group, have died in these regions. A similar immunization of all of the rest of the world's children is going on at this moment. As you may know, about 40 years ago Jonas Salk (the person for whom the Salk Institute for Research, in La Jolla, California is named), developed the first vaccine against polio. Later, Sabin improved the vaccine, and produced an oral-dose form (the form of the vaccine with which for many years, everyone in the United States has been immunized). The oral form of the vaccine is made of a live, but attenuated (non-harmful) poliovirus preparation; Salk's vaccine was a dead virus preparation. When we take the oral vaccine, the non-harmful, but alive and infectious, but not disease-causing form of poliovirus, infects our intestinal epithelial cells, where it slowly produces virus structures. We respond immunologically against these structures in a normal way (is what our immune system does), and in this way, develop and maintain a day-by-day, minute-by-minute, second-by second, life-long protection against the harmful (wild-type) form of the virus - which is pretty much all over the place (or, at least, used to be!). Therefore, if everyone is eventually immunized, there will not be anyone left within which the wild-type virus can start an infection (our boosted immune system prevents the virus from infecting any cell). Therefore, the virus cannot reproduce, and therefore, no one can transfer it to anyone else. Eventually, as was the result of a similar world-wide immunization effort against smallpox virus, it is possible that poliovirus will also be eliminated from the planet!

Book: Don't Touch That Doorknob!

Copyright John C. Brown, 1995
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