ï~~VOLUME 71 NUMBER 15 GAUZE MASKS-HAL. empyema showed, in this survey, a high incidence of diphtheria. From these facts one must conclude that, as has already been shown by others, a man from a rural community is not as great an asset to his organization in the early part of his military career as is an urban individual. CONCLUSIONS 1. A single negative culture is only of relative value, as is shown by the fact that preoperative cultures, taken from tonsils that later proved positive for diphtheria, were negative in 22.8 per cent. of the cases. 2. The importance of nasal cultures is shown by the fact that in routine cultures taken from carriers, 26 per cent. were positive from the nose. 3. Cultures from, chronic carriers should be tested for virulence. 4. The carrier state is maintained by some underlying pathologic condition of the affected tissues. 5. In the great majority of cases the carriers harbor the bacilli in the tonsils; a few carry the germs in the nose only; a small group maintains the infection in both nose and tonsils. 6. Conclusions based on the results of local treatment should be founded on careful and prolonged bacteriologic study. Cultures should be taken immediately before treatment, or, if local treatment is being TABLE 2.-OCCURRENCE OF DIPHTHERIA BY ORGANIZATIONS Organization Source 137th Infantry...............Rural.......... 138th Infantry................Urban......... 139th Infantry................Rural.......... 140th Infantry................Rural and nrban.. 128th Field Artillery............Urban......... 129th Field Artillery............ Rural and urban.. 130th Field Artillery............ Rural.... 128th Machine Gun Battalion.....Rural.......... 129th Machine Gun Battalian. Rural.......... 130th Machine Gun Battalion.......Rural.......... 110th Engineers.............R.ural and urban. 110th Sanitary Train...........Rural....... 110th Ammunition Train............Rural and urban.. 110th Military Police...........Rural.............. 110th Supply Train.............Urban.......... 110th Field Signal Battalion. Rural.......... 110th Trceh Mortar Battalion..Rural.......... Base Hospital.................Rural and urban.. Quartermaster................Rural and urban... Miscellaneous..................Rural and urban.. Carriers Pee Cent. 6.7 J.7 9.2.3 2.7 1.3 2.3 3.0 4.1 1.0 0.4 16.7 3.2 2.3 Cases Per Cent. 24.2 6.c 13.9 9.3 1.8 4.6 3.9 1.8 0.4 1.7 4.9 3.111 2.8 3.2 1.1 1.3 0.0 10.6. 2.1 2.2 LER AND COLWELL 1213 13. Toxin for the Schick test should be prepared fresh, and no diluted toxin should be used after twentyfour hours. The undiluted toxin should be kept in the dark and in a refrigerator. 14. Intermittent chronic carriers should be employed as attendants in diphtheria wards or in quarantine camps. They should be separated from the hospital personnel and from their organizations. 15. Diphtheria patients may be discharged from the hospital after they have had at least three negative cultures at three-day intervals. Chronic carriers should not be discharged until cultures taken over a long period of time prove consistently negative. We take this opportunity of expressing our appreciation for the cooperation accorded us during this study to the following members of the staff of the base hospital: Major A. C. Magruder, Capts. W. B. Post, E. E. Hopkins, A. W. Cox, H. E. Blanchard, R. Appleberry and A. E. Edgerton, Lieut. F. H. Thorne, Miss Marjorie Bates, Miss Dorothy Loomis, and Pvt., First Class, Stephens Moore. THE PROTECTIVE QUALITIES OF THE GAUZE FACE MASK EXPERIMENTAL STUDIES DAVID A. HALLER, M.D. (POCAHONTAS, VA.) Major, M. R. C., U. S. Army AND RAYMOND C. COLWELL First Lieutenant, S. C., N. A. CAMP GRANT, ROCKFORD, ILL. The use of the face mask by surgeons and their assistants to protect clean operative fields which they otherwise would spray with their own mouth organisms at every cough or sneeze is an old and well established procedure. The utilization of the face mask to protect the wearer from droplet infection in the presence of those ill with acute infectious diseases is likewise now a well established custom owing in large part to the careful studies at the Durand Hospital in Chicago. Weaver' has shown its efficacy when used in this institution in protecting attendants on infectious disease cases both from contracting these diseases and from becoming carriers of them. Capps2 has published statistics tending to confirm the work of Weaver and has proposed a new adaptation for the face mask, the essential idea being to use this mask to protect patients from cross-infection in the ambulances, and in the admission rooms and wards of the hospital. The clinical results of this adaptation of the face mask were described by Capps3 recently. The work described in this paper was carried out for several reasons. The masks used at this hospital have come from several different sources. Masks found in use in the various wards on the same day showed extreme variation in the number of layers of gauze. Some were made with only three layers, and were obviously too thin. Others were made with eight layers, and these were quite hard to breathe through; also they were very warm and uncomfortable. The gauze of which the masks were made varied in quality, 1. weaver, G. H.: The Value of the Face Mask and Other Measures, THE JOURNAL A. M. A., Jan. 12, 1918, p. 26. 2. Capps, J. A.: A New Adaptation of the Fase Mask in Control of Contagious Diseases, THE JOURNAL A. M. A., March 30, 1918, p. 910. 3. Capps, J. A.: Measures for the Prevention and Control of Respiratory Infeetions in Military Camps, THE JOURNAL A. M. A., Aug. 10, 1918, p. 448. administered, this should be suspended for a number of days before cultures are taken. The results of local treatment are problematical, since the organisms are situated deeply in the tissues. 7. In persistent carriers in whom the' focus of infection is the tonsil, enucleation offers the *only certain procedure for terminating the carrier state. 8. The most persistent nasal carriers are those in whom chronic inflammatory or atrophic processes are found. It is almost impossible, in view of the varying culture returns, to state when the condition has finally cleared. 90 Centralization of authority is necessary for the control of an epidemic of diphtheria and diphtheria carriers in camp. Release of patients from quarantine should be under the supervision of the laboratory. 10. During 'an epidemic, patients should not be admitted to a clean ward unless they have had at least two successive negative cultures from the nose and throat. 11. Improperly constructed and improperly worn masks give a sense of false security. 12. The hospital personnel should be given a Schick test, and those giving a positive reaction should be immunized with toxin-antitoxin mixture.