(4 of 9)
This week, though some state officials were giving only guarded, conditional permission for the trials, there was no doubt of the public's eagerness to see the vaccine tested, or of its faith in the mystical powers of white-coated medical researchers to exorcise the demon polio that has made each summertime a season of fear. In Pittsburgh schools, 80% to 95% of parents with children in the first three grades gave written consent for the vaccinations, and nearly all these youngsters showed up on V-day.
Among the 1.000,000 children that the foundation hopes to vaccinate there would be (by recent U.S. averages) 700 cases of detectable polio this summer. Of these. 483 would, sooner or later, recover completely, 175 would have some permanent paralysis and 42 would die. The value of Dr. Salk's vaccine will be measured by the extent to which it cuts the number of paralytic cases.
Endemic & Epidemic. It is still too early to answer the question, "Is this the year of victory over polio?" But there is good reason to believe that the Salk vaccine, or one of several on which work is proceeding in other laboratories, will give effective protection against the disease. This assurance lies in the body of knowledge, already immense and now growing faster than ever, that scientists have accumulated about polio. Most of this knowledge has been gained in the last 15 years by researchers working with grants from the National Foundation. It has taken so long because polio is full of paradoxes.
Tireless work by such researchers as Dr. William McD. Hammon of gamma globulin fame (TIME, Nov. 3, 1952) and Yale's Dr. John R. Paul shows that polio is a worldwide, natural infection of man and at least as old as civilization. And the first and greatest paradox is that the more widespread the infection, the less disease there is.
Infantile paralysis was noted as uncommon but regular and widespread (and therefore endemic) by Britain's Dr. Michael Underwood in 1784. Sweden had the first reported epidemic of polio in 1887. Seven years later came the first U.S. epidemic, in Vermont's Otter Creek Valley. Around Rutland and Proctor there was no fewer than 119 paralytic cases. By brilliant horse & buggy epidemiology, Dr. Charles S. Caverly concluded that the old endemic infantile paralysis and the new epidemic polio were one and the same disease.
Bit by bit it became clear that polio is caused by a virus, the "ultimate parasite'' of nature that can multiply only within living cells of a higher order—and is too small to be seen by any pre-electronic microscope. Unlike most other disease-causing microbes, this virus does its damage only by attacking the central nervous system,* paralyzing nerve centers and pathways that control distant muscles. Nerves governing the legs, arms and breathing are particularly susceptible. In the severest and commonly fatal bulbar cases (involving the bulb at the base of the brain), speech and swallowing are affected as well as central breathing control.