Notes on preventive medicine for medical officers, United States Navy : instructions to medical officers / Department of the Navy, Bureau of Medicine and Surgery.

  • United States. Navy Department. Bureau of Medicine and Surgery.
Date:
1918
Catalogue details

Licence: Public Domain Mark

Credit: Notes on preventive medicine for medical officers, United States Navy : instructions to medical officers / Department of the Navy, Bureau of Medicine and Surgery. Source: Wellcome Collection.

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    3: In the cities listed above there have been 59,089 deaths from influenza and pneumonia during the seven weeks ended October 26, 1918. The figures by weeks are as follows: Disease. Sept. 14. Sept. 21. Sept. 28. Oct. 5. Oct. 12. Oct. 19. Oct. 26. Tntluen das 2 ke oS 19 193 904 2,718 6,809 | 12,303 13, 086 Pronmoniact. ooo reas 299 405 853 | 2,043| 4,602] 7,646 7, 209 NotEs FROM THE Unirep Srates Navat Trarnine Station, Navat Operating BAss, Hampton Roaps, Va. The laboratory of the United States naval operating base, Hampton Roads, Va., reports the results of examinations for intestinal parasites as follows: Method of examination —The method described by Bass has been followed throughout. A piece of stool approximately the size of a hickory nut is emulsified in 20 c. c. of water in a large test tube and then strained through several layers of gauze into a centrifuge tube to remove the coarser particles. The filtrate is centrifugalized at bigh speed for e:ght seconds; the supernatent haw is poured off and the sediment at the bottom of the tube is again thor- oughly emulsified in 15 c. ce. of water. It is centrifugalized at high speed for five seconds, the supernatent fluid is poured off, and the residue at the bottom of the tube is emulsified on a slide and examined with the low-power microscope. An effort should be made to place practically all of the residue on the slide after the second washing. Small sections of wooden applicators have been found useful for making the final emulsion on the slide. Centrifuge tubes with rather blunt bottoms are easier to manipulate than those with a finer point. A third washing undoubtedly gives a clearer field for examination, but whether the results obtained justify the time and trouble is questionable. After some experience hookworm eggs may be readily detected despite the finer particles which may, at times, be present when only two washings are given. We do not believe that the method of Bass will enable one to demon- strate all of the positive cases, but the same may be said of all methods of examination. Efforts made to show an increase in the percentage of infections by reexamination of the sediment and other means have been barren of results. The method employed by Kielty and Haverkampp, consisting of a single run in the centrifuge for 15 seconds at high speed followed by immediate examination, has been tried, but is not considered as serviceable as the method of Bass. The method employed by Trabue of depending simply upon emulsification and gravity was employed by him because no centrifuge was available. It is obviously not to be compared with other methods. It is amazing that he obtained so high a percentage of positives with such a simple technique. We believe that the method used by Bass will enable one to find the great majority | of eggs present, and that it is a technique to be highly recommended. Our findings correspond very closely with the figures obtained for recruits in the United States Army as reported by Trabue and by Kielty and Haverkampp. ‘The number of positives varies widely for recruits from different States. However, it may be assumed that recruits from the Southern States will run in the neighborhood of 20 per cent positive for hookworm and that a considerable number will harbor other forms of intestinal parasites. Kielty and Haverkampp found as follows: Recruits examined, 8,277; positive for hookworm, 1,504, or 24.4 per cent. Line officers examined, 152; positive for hookworm, 5.2 per cent. Medical officers examined, 108; positive for hookworm, 6.9 per cent. Trabue gives: Examined, 3,774; positive for hookworm, 659, or 17 per cent. Other forms of intestinal parasites were not counted. In the laboratory at the naval operating base, 1,073 samples of stools have been exam- ined, with the following results: 267, or 24 per cent, were positive for hookworm; 42, or 4 per cent, were positive for trichuris; 29, or 2.79 per cent, were positive for ascaris; 22, or 2.10 per cent, were positive for hymenolepis; 3, or 0.27 per cent, were positive for oxyuris. In addition to the above, several forms of ova were seen which we were unable to identify. The results of examinations in a small group of hospital patients are included in the list. the findings did not vary from the others to any degree, it was thought proper to group them together. Any variation noted in the future will be commented upon.