1954 Poliomyelitis Vaccine Field Trial

Early in 1953 Salk reported that a formaldehyde (Formalin)-treated virus vaccine, prepared in his laboratory, had produced neutralizing antibodies against all three types of poliomyelitis virus in children who possessed no demonstrable circulating antibodies against these viruses before vaccination.1This trivalent vaccine appeared to be noninfectious; inoculation of human subjects was free of untoward reactions. Moreover, the method of inactivation with formaldehyde, developed at the University of Pittsburgh Virus Research Laboratories, appeared to provide a wide margin of safety in dissociating virus infectivity from its antigenic properties. Inactivation proceeded as a first order chemical reaction, thus permitting ready standardization and rigid control. Experiments in progress gave promise of the early development of even better antigens, capable of inducing persistently high levels of neutralizing antibodies comparable to those observed in individuals who had experienced naturally occurring infection and clinically recognized disease. Immediately after publication of this report, a distinguished group,