Poliomyelitis (shortened to polio) has been around for thousands ofyears, and there is still no cure, but at the peak of its devastation in the UnitedStates, Dr.
Jonas Salk introduced a way to prevent it. Polio attacks the nervecells and sometimes the central nervous system, causing muscle wasting,paralysis, and even death. The disease, whose symptoms are flu like, stuckmostly children, and in the first half of the 20th century the epidemics of poliowere becoming more devastating. Salk, while working at the Virus ResearchLab at the University of Pittsburgh, developed a polio vaccine, and themedical trials to prove its effectiveness and safety are still being analyzed.Fifty years ago the largest medical experiment in history took place totest Salks poliomyelitis vaccine. Close to two million children across theUnited States and Canada were involved in the trial, which was administeredby the National Foundation for Infantile Paralysis (NFIP), also known as theMarch of Dimes. The foundation, created in 1938 by President Franklin D.Roosevelt (a polio victim) and his law partner Basil OConnor.
Across theUnited States, 623,972 school children were injected with the vaccine or aplacebo, using a double blind technique in which neither recipient noradministrator knew which one there were getting. The results, announced in1955, showed good statistical evidence that Jonas Salks killed viruspreparation was 80-90% effective in preventing paralytic poliomyelitis.The statistical design used in the experiment was singular, promptingcriticism. Eighty four test areas in eleven states used a textbook model: in arandomized, blinded design all participating children in the first three gradesof school (ages 6-9) received injections of either vaccine for placebo andwere observed.
At the same time though, 127 test areas in 33 states used anobserved control design: where the participating children in the secondgrade received injections of vaccine, no placebo was given, and children in allthree grades were then observed for the duration of the polio season. The useof the dual protocol illustrates both the power and the limitations ofrandomized clinical trials. The control trials with the placebo were importantto define the vaccine as the product of scientific medicine, while the observedtrials were done to maintain public support for the vaccine.In 1953, Salk presented his tests of a polio vaccine to the ImmunizationCommittee, the scientific advisory committee for the NFIP. The test resultsseemed promising to Basil OConnor, as the children had shown no ill effectsand the levels of polio antibodies in their blood had risen.
However, severalof the senior virologist on the committee questioned the relation of antibodiesto permanent immunity. Despite the virologists critique, OConnor believedthat his organization owed it to the volunteers and donors to proceed andcalled for the planning of a major field study.OConnor, in November of 1953, announced that the field trials wouldbegin in the spring and the observed plan would be used. Within a month,health departments in 38 states had responded, enthusiastic about theprospect of a vaccine. A few state officials however, questioned theimpartiality of the evaluation run by the foundation, and not by scientists.
Responding to the criticism OConnor called an meeting of an advisorygroup to review the statistical design. When the group convened, it haddecided to go strictly with the placebo controlled studies.This change lessened slightly the criticism of the field trials, and theNational Foundation for Infantile Paralysis tried to reconcile it scientific andpolitical problems by working through state health departments. The criticsstill denounced the trials as flawed, and the debates of the scientific validityof the experiment continue to this day.Words/ Pages : 570 / 24