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]
Catalogue details

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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    period of incubation is in nowise proportionate to tbe quantity used for inoculation, and (2) that in the so-termed second generation of infection, septichsemic blood is already infective in the TooVoo^h °f a drop. Infection was then transmitted through the fourth, fifth, and sixth generations, by inoculation with similar small quantities and like results, the animals dying respectively within 23, 48, and 20 hours. The blood of this latter—the sixth generation—was diluted to different degrees, and ten drops of the solution injected into four other rabbits, which received—No. 11, TWo^h gtt.; No. 12, y^tli; No. 13, tooVoo i No- 14> T<nreooootb of a dr0P- Ttiese died all in my presence in, respectively 20, 26, 25-|, and 20 hours, showing in addition to the first point above-mentioned, that there is no appreciable shortening of the incubation period between the second and the sixth generation. As the blood here proved to be infective in the ten- millionth part of a drop, it was now necessary to determine the limits of infectivity in the first generation. Again five drops of putrid bullock’s blood, diluted with an equal bulk of saline solution, were injected into a rabbit, No. 15, which died within 48 hours; its blood was diluted as before, and ten drops injected into each of five other rabbits, so that they received—No. 16, one-thousandth; No. 17, one hundred-thousandth; No. 18, one- millionth ; No. 19, one ten-millionth; and No. 20, one hundred- millionth of a drop. No. 16 died in 24 hours, Nos. 17 and 18 died within (that is, were found dead in) 35 hours, and No. 19 within 48 hours; No. 20 was apparently unaffected ; subsequently, however, it lost flesh, though continuing to feed, without any material rise in temperature or the occurrence of microphytes in the blood, and a small abscess was found at the spot of injection, which suppurated and healed spontaneously in about eighteen or twenty days, and the animal recovered. From this series of experiments it appeared that the blood of an animal poisoned by inoculation with putrid matter, in the so-termed first generation, is infective in less than the millionth part of a drop, and the considerations mentioned below showed that it was useless attempting to investigate the limits of infectivity beyond this point; but in order to ascertain whether there occurred subsequently any appreciable shortening of the incubation period, as was considered to be the case by MM. Coze and Feltz, infection was transmitted in succession up to the tenth generation, in which the blood of a rabbit that had died septichsemic, was again diluted as before, and ten drops, each of the same dilutions as in the last-recorded experiments, injected into four other rabbits, one-thousandth, one-millionth, a ten-millionth, and a hundred-millionth of a drop respectively into rabbits Nos. 21, 22, 23, and 24, which died, No. 21 in twenty-one hours, while the other three survived upwards of twenty-seven, but died during the night within