The virus cannot live in immunized individuals, nor in nature.
H.) protection against plague; (2) on the comparative liability of each fluid to contamination; and (3) on the probable origin of tetanus virus in the Malkowal cases.
This virus causes the rapid enlargement and subdivision of the cells affected by it, so as to form the tissues of the gall.
Specifically, a virus or bug passed to a pig is considered a huge threat in the medical community, because pigs can pass their diseases onto humans.
The exciting cause of the hypertrophy, in the case of the typical galls, appears to be a minute quantity of some irritating fluid, or virus, secreted by the female insect, and deposited with her egg in the puncture made by her ovipositor in the cortical or foliaceous parts of plants.
In producing active immunity by the attenuated virus, Duguid and J.
But by a process of successive and continued artificial cultures under different conditions, the virus of the organism is found to become attenuated; and when this weakened virus is administered, the animal is rendered immune against further attacks.
The next step was to endeavour so to modify and weaken the virus as to enable it to be used as a preventive or as an antitoxin.
Would the inoculation of the attenuated virus have a remedial effect on an animal already bitten ?
Simpson in his Report on the Causes of the Plague in Hong Kong (1903) reports the endemicity of the plague in that colony to be maintained by (a) infection among rats often connected with infectious material in rat runs or in houses, the virus of which has not been destroyed, (b) retention of infection in houses which are rat-ridden, and (c) infected clothing of people who have been ill or died of plague.
Rats should be exterminated as far as possible, especially by means of the Danysz virus, which spreads a disease amongst rats which cannot be communicated to man.
At Hubli, where nearly the whole population was inoculated between the lath of May and the 27th of September ' The system of inoculation against plague with a fluid prepared from sterilized virus of the disease was introduced in India by Professor Haffkine early in 1897.
On the other hand, he found the weakened virus could be again strengthened by inoculating a feeble animal such as a guinea-pig a day or two old with it, and then inoculating stronger and stronger animals: an increase in strength was gained with each inoculation, until at last the virus could attack the strongest.
Probably the same disease, the virus of which is modified and its virulence lessened by passing through the body of the cow.
By inoculating first with a weak virus and then with others which were stronger and stronger, he was able completely to protect oxen either from the effects of inoculation with the strongest virus or from infection through contact with other animals suffering from the disorder.
In all these cases the virus seems to have come from Holland; the last two executions followed the rash dedication to James I.
Long before any clear ideas as to the relations of Schizomycetes to fermentation and disease were possible, various thinkers at different times had suggested that resemblances existed between the phenomena of certain diseases and those of fermentation, and the idea that a virus or contagium might be something of the nature of a minute organism capable of spreading and 1 Cladothrix dichotoma, for example, which is ordinarily a branched, filamentous, sheathed form, at certain seasons breaks up into a number of separate cells which develop a tuft of cilia and escape from the sheath.