TJ. S. VETERINARY MEDICAL ASSOCIATION. 
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tion, where the development is completed inside the body, and the infecting 
element is thrown off from the body in a condition capable of producing the 
same disease in another individual. 
A great deal of attention is being given at present to those diseases in which 
there is very considerable evidence of their miasmatic origin. As already stated, 
the typical miasmatic disease in man is malaria. Its association with non-bac- 
terial micro-organismal infection dates from the researches of Laveran, in 
Algiers, communicated to the Paris Academy of Medicine in 1881-1882, as also 
in a large work on the malarial origin of fevers in 1884. As characteristic ele¬ 
ments of the blood of persons affected with malaria were found : 1. Pigmented 
bodies in the interior of red blood corpuscles, which underwent amaboid changes. 
2. Crescentic pigmented bodies; 3. A pigmented flagellated organism. 
These investigations have since been confirmed by several observers, among 
them Marchiafava and Creeli,and by Dr. Councilman, of Baltimore, Md. 
In 1880, Veterinary Surgeon Griffith Evans described a very fatal disease in 
horses, mules and camels in India. He discovered a parasite in the blood dur¬ 
ing life which he first described as a spirillum, but afterward concluded it was a 
much higher organism. In 1885, Steel found the same parasite as described by 
Evans, and regarded it as a true spirillum. From clinical observation he con¬ 
cluded that the disease was very closely related to recurrent fever of man. Both 
Steel and Evans found the disease readily communicable, either by injection or 
inoculation to dogs, horses, and mules. Cruikshank afterward determined the 
bodies found in the blood to be a flagellate organism belonging to the group of 
infusoria. 
Burke, Nissum, Raymond and others have written much upon diseases of 
the malarial type in animals. Some interesting and apparently very accurate in¬ 
vestigations have recently been made by Dr. Theobold Smith, of the Bureau of 
Animal Industry at Washington, D. C. The results of these investigations were 
published in a paper entitled “ Preliminary Observations on the Micro-organism 
of Texas Fever,” read at the Brooklyn meeting of the American Public Health 
Association, October 23d, 1889. He says: “Southern cattle fever or Texas 
fever, as it is more popularly known, is an infectious disease of the malarial 
type.” * * * “ The infectious agent, bound to a particular locality, is only 
temporarily transferred by cattle to places free from permanent infection.” He 
experimented upon some native cattle by placing them in the same enclosure 
with healthy cattle shipped from North Carolina. The experiment was per¬ 
formed at the experimental station in Washington. “ The first death occurred 
in August.” * * “ Up to the last week in October, ten had succumbed to the 
disease and two recovered.” * * * There was also a continual increase or 
accumulation of the virus in the enclosure, for the animals placed on the grounds 
late in the season died after an exposure of but one-half to one-tliird the period 
which was necessary to destroy those exposed since early summer.” In¬ 
vestigations looking toward the bacterial origin of the disease resulted negatively. 
He found, however, “small round bodies, perhaps 1 m. in diameter, centrally 
or somewhat eccentrically situated in or upon many red blood corpuscles, which 
stain fairly in an aqueous solution of methyl violet. They there resemble micro¬ 
cocci in size and form. Unstained they can be seen as pure transparent spaces 
in the corpuscles.” 
