TLS signed “Jonas E. Salk,” three pages, 8.5 x 11, University of Pittsburgh School of Medicine letterhead, December 27, 1954. Letter to Dr. William Workman of the National Institutes of Health, in full: "I have just received from your office a number of copies of Amendment No. 2 to Minimum Requirements for Poliomyelitis Vaccine, under date of December 14, 1954. Since there was no covering letter requesting comments, I take this to mean that the tentative draft sent to me on 24 November is now in its final and accepted form.
In your covering letter to me on 24 November you indicated that the tentative draft of Amendment No. 2 dealt mainly with the potency test in monkeys, as discussed in Pittsburgh, on 21 November. You then asked for my frank comments and suggestions for revision; I sent these to you promptly. I now find that you have accepted a monkey potency test, presumably on the basis of the draft, as initiated here, but yet 'the end result is not in accord with the principles upon which the test we proposed was based.'
It would have been far more acceptable to me if you were to write, in response to my letter to you of 30 November, or my other recent communications, and say that you disagreed with the suggestions I had made, and had stated the reasons for this disagreement. Under such circumstances I would, at least, have had the opportunity of discussing with you, once again, the theoretical and experimental basis for the suggestions that were made, and with which you apparently agreed. Instead, your office sent to me Amendment No. 2, dated 14 December, which, in effect, has altered, both in principle and in detail, the test that we have proposed. I can tell you quite emphatically, that many of the changes from the original are not in accord with the principles upon which the test we proposed is based. I am quite sure that if inquiries were put to you for justification for the test proposed, you would say that it was based upon work in Salk's laboratory. I want to assure you that we cannot accept responsibility of this kind.
I find myself, once again, in the same position that I did in relation to two earlier problems and I cannot remain in such a position this time. One such instance had to do with the use of merthiolate in the vaccine, and another had to do with the question of safety-testing. I am at a loss to understand why there is still discussion of the safety tests for poliomyelitis vaccine. Apparently there is little or no confidence in a test merely of a sample of a total batch; and, with this view I am in complete accord. But, at the same time, the value of a safety test, which is based upon the rate of virus inactivation, is still not acknowledged. I wonder whether the reasoning in connection with the latter is the same as that which has led to 'the introduction of fundamental modifications in the monkey potency test proposed by us.'
There have been many occasions when representatives of the National Institutes of Health have said to me personally, or to the National Foundation for Infantile Paralysis, 'Does the Vaccine Advisory Committee know about thus and so?' Based upon the opinion of the Vaccine Advisory Committee, the NIH believed it possible, in the past, to proceed under circumstances when they might not have been willing to do so without this reassurance. Would it be improper for me to ask for the basis upon which the decisions concerning poliomyelitis vaccine are being made? Specifically, I would like to know (1) the basis for the changes from the agreement reached in Pittsburgh, on 20-21 November, concerning the monkey potency test, and (2) the basis for the implications, with which I believe you are in accord, that a vaccine without merthiolate, in a concentration of 1:10,000, may not be as safe as one prepared with merthiolate.
It seems to me that factions have developed in relation to a problem that has a single goal. This is not only inappropriate but unfortunate. My only purpose is to help, in whatever way I can, to bring about the conclusion of the problem of poliomyelitis. I want 'to be of help to whomever is in a position of responsibility for whatever action seems indicated' and I know you feel, as I do, that we can act only on the basis of facts acquired by experimentation and experience. In this way we approximate the truth and reduce dependence upon opinions. But there are stumbling blocks to the acquisition of truth, as Roger Bacon so clearly understood and phrased so well:
1. Influence of fragile or unworthy authority.
2. Custom.
3. The imperfection of undisciplined senses.
4. Concealment of ignorance by ostentation of seeming wisdom.
You have every right to feel that my experience and judgment are of insufficient weight to over-balance the advice that you are now receiving, but I can be of further help only if I know the basis for your thinking. I hope you will accept this letter in the spirit in which it is written and that the problems remaining can be resolved in the clear dawn of the year ahead." In fine condition. Accompanied by a two-page carbon copy of Workman's response.
Beginning in 1948, Salk dedicated himself to polio research and to the development of a polio vaccine. After successful tests on laboratory animals in 1952, Salk began to test the vaccine on children. The year 1954 marked the famous, large-scale field tests of the vaccine: Salk tested the polio vaccine on about one million children, known as the polio pioneers. The vaccine was announced as safe on April 12, 1955.