On the infectivity of the blood and other fluids in some forms of septic disease, and the reputed occurrence therein of an increase of virulence in successive inoculations / by G.F. Dowdeswell ; communicated by M. Foster.

  • Dowdeswell, G.F.
Date:
[1883]
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Licence: Public Domain Mark

Credit: On the infectivity of the blood and other fluids in some forms of septic disease, and the reputed occurrence therein of an increase of virulence in successive inoculations / by G.F. Dowdeswell ; communicated by M. Foster. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    reproducing in other animals those symptoms which have occurred in it, though previously asserted by others, was first conclusively demonstrated in 1866 by MM. Coze and Feltz in France,* who further stated that in successive inoculations from one animal to another of the same species, such blood acquires a progressive increase of virulence, becoming more toxical than putrid matter itself, and that death follows inoculation with increasing rapidity. These observations were confirmed and greatly extended by Davaine, f in long investigations; hence the form of septicheemia here in question has since been known by the name of the latter observer. The first- mentioned writers founded their assertion of an increase of infective virulence upon the alleged fact that in successive inoculations! the incubation period was progressively shortened; whereas Davaine sought to show, by numerous experiments, that in the same manner succes- sively smaller quantities of blood were required to create infection ; that whereas to originate it some drops were necessary, ultimately, after several generations of transmitted infection, the billionth (in the French notation the trillionth) part of a drop, or less, was sufficient; but he regarded, indeed defines, septichaemia as a putrefaction of the blood in the living animal, a view naturally encouraged by the decom- position which in these cases occurs so rapidly after death. Davaine’s experiments were repeated by many observers, both in France and elsewhere.§ It is remarkable, however, that they one and all contented themselves with merely reproducing his earlier obser- vations, inoculating in succession several animals with constantly diminishing quantities of blood, but without making any control expe- riments to ascertain whether in the first stages the blood was not already infective in the degree supposed to be attained only after several generations, and overlooked the fact that, in his later writings|| Davaine had qualified his first statements by showing that a maximum of infectivity was attained in the earlier generations. These conclu- sions and the theory of an increase of infective virulence in successive inoculations have since been generally accepted ; but the question here * “ Recherches Cliniques et Experimentales sur les Maladies Infectieuses, &c.,” Strasbourg, 1866. and Paris, 1872. f “ Comptes Rend, de l’Acad. des Sc.,” Paris, Feb. 1, 1869, et passim. Also “ Bull. Acad. Med.,” Paris, 1872, p. 907, &c. t Or, as it was termed, “ generations,” with reference to the microphytes found to be present in the blood of these cases, which were regarded as constituting the active contagium, and which by propagation in the blood of living animals, it was said, acquired “ renewed vigour ” in successive generations. I have retained this term “ generations ” as convenient, but without here implying anything more than successive inoculations from one animal to another. § As by H. Dreyer, “ Archiv. f. Expt. Path. u. Pharm.” 1874, Bd. II, s. 149, &c., and Clementi and Thin. || Loc. cit., “Bull. d. l’Acad. de Med.,” 1873, p. 124, &c.