Experiments and observations on the vitality of the bacillus of typhoid fever and of sewage microbes in oysters and other shellfish : investigations on behalf of the Worshipful Company of Fishmongers, London / by E. Klein.

  • Klein, E. (Edward), 1844-1925.
Date:
[1905]
Catalogue details

Licence: In copyright

Credit: Experiments and observations on the vitality of the bacillus of typhoid fever and of sewage microbes in oysters and other shellfish : investigations on behalf of the Worshipful Company of Fishmongers, London / by E. Klein. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    lished the differences in a striking manner. (1) They failed to grow in all media, if these are incubated at 37° C.; there was no perceptible growth at this temperature either on agar, or in broth, or in milk. (2) They completely failed to alter MacConkey fluid at 37° C. ; B. typhosus turns it red, but forms no gas. (3) They failed to cause any change in litmus milk ; B. typhosus forms gradually acid (red) without altering the fluid character of the milk. (4) They produced no growth either in neutral red broth or in phenol broth. In addition to these differences the microbe grew very slowly on gelatine : it took two to three days before any distinct growth could be noticed, and then it was very trans- parent, unlike that produced by B. typhosus; and, lastly, in shake gelatine it did not form its colonies in the depth of the medium like the B. typhosus, but, besides being much slower in its growth, it formed colonies only or principally near the free surface of the medium. It is therefore clear that this microbe need cause no difficulty in the search for the B. typhosus on Drigalski plates kept at 37° C, being a microbe not capable of growing at that temperature. (b.) Of the most frequent blue or violet colonies found in Drigalski plates inoculated with sewage or f»cal matter, with sewage or fsecalmatterpoUuted shellfish—oysters, mussels, and cockles—are those of streptococci. These appear already after 24 hours at 37° C.; better and more conspicuously later as violet-blue small round dots, uniformly raised and moist looking. A particle of a colony emulsified and looked at under the microscope is at once recognised as a compound of diplococci and short streptococci. They possess the additional character of staining with gram. Owing to their small size, their violet-blue colour, and their appearance under the microscope, viz., being cocci, they need not further offer any difficulty in respect of being mistaken for anything else. (c.) Eepeatedly I have come across in Drigalski plates at 37° C, that had been inoculated with sewage, bright bkte small colonies, more or less conical in shape. They are composed of vibrios or comma bacilli; they resemble in size, shape.