November 3, 1944 Dear Dr. Heidelberger: We have finally begun the bleedings. The first lot of eight (8) samples will leave here by air on Monday, November 6. Inclosed is a list of the subjects from which the blood was taken made up in the form which we decided upon when I saw you in New York. As you will see, the first four (4) bloods are from Laboratory personnel. Major Bernhard and myself received another 1 cc of the polysaccharide immediately after this blood was taken and we will bleed each other again in five or six weeks. The other four (4) bloods are from incoming students who received 1.5 ccs after bleeding. We shall bleed these men again in four to five weeks. We have not yet been able to obtain satisfactory centrifuge tubes and there may be some red cells in the serum. However, if it does not make too much difference with the tests, it would be much easier for us to separate the serum by decanting from the clotted blood. In that way we could avoid contamination, which is likely to occur with the somewhat crude set-up we have for separation. If the red cells do interfere with the test, please let us know as soon as possible and we shall make every effort to get rid of them. Winter has not yet arrived at Sioux Falls and the pneumonia rate is remaining very low indeed. We have had four (4) cases of type 2 pneumonia since we gave the inoculations. All four of these received the saline solution and not the polysaccharide. Given another four, we may be able to use the word "significance", but still with moderation. The prospect of there being more pneumonia is good since our carrier rate still remains about 50% and types 1, 2, 5 and 7 comprising about 6% of the types that we get. Given the proper environmental circumstances such as a good blizzard, I strongly suspect that our pneumonia rate will pick up. As I said in New York, if there are any other aspects of the problem that you wish us to tackle from your point of view, do not hesitate to let us know. We are receiving very good cooperation and can handle any "arbeit" within reason. Incidentally, we are saving duplicate copies of the listings of all the samples which we send to you so that if there is any confusion, I am sure that we can straighten it out. Give my regards to any of my friends whom you may meet in the dining-room, particularly Rusty McIntosh. Yours most truly, Richard G. Hodges Captain, MC Epidemiologist