Co-discoverer and -developer of the polio vaccine (1914–1995). TLS signed “Jonas,” four pages, 8.5 x 11, Salk Institute letterhead, October 5, 1978. Salk writes to Dr. Armand DeSanctis regarding studies on increasing the effectiveness of the polio vaccine. In part: “The essential point to make is the need for an animal assay that might be capable of discriminating between two killed poliovirus vaccines that differ in potency by two-fold…. A study is about to be started … to see if a two-fold difference would be discernible in a titration in humans over a two-fold dilution range…. The advantage of having these preparations is that the results would then also be related to the performance in humans…. Since we can look forward to the possibility that a third generation of poliovirus vaccines may be made of purified antigens, or even antigens produced using recombinant DNA, or even biochemical synthesis, it would be very desirable to develop a reliable, efficient and economical method for in vivo assay of antigenicity….” A touch of mild soiling and handling wear, otherwise fine condition. R&R COA.
