Mortality. Among native cattle in the Steppes the mortality is 30 to 50 per cent. whereas elsewhere it is 90 to 95 per cent. Among sheep in Austria it reached 60 to 66 per cent. Among camels in Asia and Africa the fatality proved as high as among cattle. The Italian buffalo usually recovered after seven days illness.
Treatment. The therapeutic treatment of cattle affected with cattle plague has been eminently unsatisfactory and is so certain to become a means of extension of the disease that it is legally prohibited in all countries, in which the plague has not been allowed to become generally diffused. Where it has become general in an unfenced country in which accordingly its permanence is virtually ensured, it may be employed.
Serum-therapy is advocated by Refik Bey. An animal is hyper-immunized by repeated inoculations. His blood is then withdrawn and the serum obtained from it is injected in a dose of 25cc., subcutem, at a temperature of 104° F. The temperature is taken from the 3d to the 5th day and if it does not at this time rise above normal the treatment is ended. If still above normal a second dose of 25cc. is given. It is claimed that the serum is harmless and may be safely given in a single dose of 50cc. in case it is impossible to keep watch of the animal for five days.
Prevention by Immunization. Semmer attempted this by inoculating cattle with virus which had been weakened by heat or by passing it through the body of a Guinea pig. The results were, however, far from perfect and even in Russia the method failed of any wide acceptance. Koch and Edington in South Africa practised extensive inoculations with a mixture of the virus in bile. Still better results are claimed by Danyoz, Bordet and Theiler in the Transvaal. These treated the animals by injecting 25cc. to 50cc. of highly immunized blood, defibrinated, and while the subjects were thus rendered temporarily insusceptible, they were exposed to infection by contact with diseased animals.
As with serum-therapy, measures of this kind are only permissible in a country in which cattle plague is already generally diffused, and where there are no fences to limit the continued diffusion of the infection. The preservation of the cattle artificially infected until highly immunized, and again of the sick cattle requisite to give the disease to the cattle operated on, and finally of these last through the mild attacks that are to render them immune, affords an endless number of loopholes for the escape of contagion which would forbid the adoption of the method whenever the extinction of the disease is possible. When on the other hand a disease is already spread universally in a country destitute of fenced enclosures, in which herd mingles with herd in the most perfect freedom, and where accordingly extinction is impossible, the method is admissible and even commendable as a means of reducing the otherwise ruinous mortality.
Exclusion and Extinction of Cattle Plague. For countries adjoining lands infected with cattle plague such general measures as the following are imperative: Prohibition of all imports of cattle, sheep and other ruminants, camels and swine from such infected countries, also of the fresh hides and other products of such animals, and of litter, fodder and other things that may have been stored in the buildings with infected cattle or otherwise soiled by them. Prohibition of imports of all cattle or other ruminants from adjacent countries (which may be plague-free), but which animals have been carried in undisinfected cars or boats that had been in previous use for such species of animals drawn from infected countries, or that had been passed through infected countries, yards, buildings, loading banks, chutes, piers, gangways, or other places, or furnished with fodder, halters or appliances from such infected localities. In Eastern Europe the practice is to patrol the frontiers day and night to prevent the smuggling of cattle through from the infected country. Infected animals or herds, that it is sought to pass, are turned back or slaughtered. Sheep from countries that had been previously infected are often admitted on affidavit of the official veterinarian in the country from which they come, that during the three months before they left, there had been no contagious disease of cattle nor sheep in the locality, and on the further condition that they shall be slaughtered at the point of entry, or, if brought by rail, at the nearest slaughter house approached by such railroad after entry. In France, sheep, sent from Russia by sea, in French bottoms, certified as above by the Russian authorities, and accompanied on the voyage by a French veterinarian and certified sound by him, are allowed to circulate freely after three days detention at the port of arrival without evidence of disease.
In the United States the 90 days quarantine of cattle (dated from the time of shipping at the foreign port), and the 15 days for sheep and other ruminants under strict veterinary supervision is safe as regards the importation of cattle plague in live animals. The greatest danger will doubtless come from intercourse with the Phillipines, which were infected with the cattle plague during the recent war. The greatest possible precautions as regards the carriage of cattle on transports or other ships, will be necessary. Not only should no Phillipine cattle be imported, but no vessel, that has carried Phillipine cattle or sheep, should be allowed to take on board home cattle nor other ruminants until it has been thoroughly disinfected.
Cattle or sheep should be rejected when imported on ships which, on the same voyage or a recent one, carried fresh hides or other fresh products of animals, derived from a country in which rinderpest exists.
Hides that are thoroughly dried and salted, those that have been freely exposed for one week to the sun and air, and such as have been treated by active antiseptics, (caustic quicklime, mercuric chloride, lime chloride, formalin, phenic acid, etc.), need be held under no such restriction. The same applies to thoroughly dried, sunned and aired hair, wool, hoofs, horns, bones and sinews. Rendered tallow is equally safe.
Extinction of Cattle Plague in a Country. This should never be called for on the American Continent. The introduction of such a deadly disease, with such a short period of incubation, and such severe symptoms and rapid course, would argue a most reprehensible carelessness, which it is to be hoped will never be shown by the Federal Bureau of Animal Industry. Yet under the stress of a great European war this plague invariably overleaps the barriers successfully maintained in time of peace, and the same has happened to the two great English-speaking powers in connection with the wars in South Africa and the Phillipines respectively and therefore it cannot be said that importation is impossible under any possible circumstances.