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Show Spread of Disease by earthworms. Recent researches by M. Pasteur appear to throw considerable light on the origin of anthrax, or splonic? Fever, and allied disease, which attack cattle, sheep, etc. (If animals, why also may not man be seriously affected by the same mode of spreading other disease germs?) When an animal dies of anthrax it is not uncommonly buried on the spot. The conditions of putrefaction prove fatal to the small parasitic organisms, or bacterium, which is abundant in the blood at death. The gas given off causes it to break up into dead and harmless granulation. But before this can occur not a little of the blood and humors of the body have escaped into the ground about the carcass, and here the parasite is in an aerated medium favorable to the formation of germs. These corpusenlar? germs M. Pasteur has found in the soil, in a state of latent life, months and years after the carcass was buried, and by inoculation of guinea pigs with them has produced anthrax and death. Now it is specially notable that such germs have been met with in the earth at the surface above the place of burial, as well as near the body. The question arises. How cam they there? And it would appear that earth-worms are the agents of conveyance. In the small earth cylinders, of the particles, which those creatures bring to the surface and deposit after the dews of morning or after rain, one finds, besides a host of other germs, the germs of anthrax. (The same process was proved also by direct experiment; worms kept in ground with which bacterium spores had been mixed were killed after a few days, and many of the spores were found in the earth cylinders in their intestines.) The dust of this earth, after the cylinders have been disaggregated by rain, gets blown about on the neighboring plants, and the animals eating those thus receive the germs into their system. It is suggested that possibly other diseases germs, not less harmless to worms, but ready to cause disease in the proper animals, may be in like manner conveyed to the surface in cemeteries. The Scientific American suggests that this should also furnish a fresh argument for cremation. The practical inference as to anthrax is, that animals which have died of this should not be buried in fields devoted to crops or pasturage, but (wherever possible in sandy, calcareous ground, poor and dry-unsuitable, in a word, for worms. |