Foot and Mouth Disease.—This has been repeatedly introduced into the United States in cattle, sheep and swine, and by cowpox virus, and has secured a wide and threatening prevalence on different occasions. It is per haps the most contagious of cattle diseases, and since other cloven-footed animals (sheep, goats and swine) are about equally susceptible with cattle, and other warm-blooded races and man are only slightly less so, it has at times caused much apprehension and dread; veterinarians have pronounced it dangerous and fatal, and government authorities have enjoined that all infected animals, herds and flocks be promptly slaughtered and the places disinfected. It is, however, one of the mildest and least fatal of cattle diseases, proving lethal only when the infection has been swallowed in the food (milk, water, soiled fodder, etc.) and has set up the diseased process on the alimentary canal (stomach, bowels). As usually occurring it shows itself in isolated blisters one-third to one inch in diameter on the mucous membrane of the muzzle, lips, cheek, tongue and throat, on the teats and between the hoofs (extending up in front and behind). Each blister shows but one undivided sac filled with a clear serum (a cowpock of about the same size is separated by internal partitions into a number of separate sacs and must be pricked again and again to empty it). The disease has a period of incuba tion of from two to eight days in cold weather, followed by some dullness in appearance and rise of body heat, a pink color of the membrane of the mouth, heat and some tenderness of the teats and between the hoofs, and soon move ments of the jaws, accumulations of white froth in masses around the lips and a driveling of liquid saliva. A loud smacking usually follows caused by gaping, parting of the lips and sep aration of the tongue from the roof of the mouth. The simultaneous attack of the whole herd and the concentration of the lesions on the three points named make a characteristic picture. The implication of sheep, goats or swine in the same building, yard or road is equally striking. The rule is that when kept clean, fed soft, sloppy food and treated with mild antiseptics, the patients improve rapidly and are well in 14 days, and after an attack they can be considered immune for a length of time. They may have a second attack a year later. As reassuring data it may be stated that in the United States, and in Great Britain it was the rarest thing to have a death occur. McMinn's cattle insurance statistics, cov ering long periods of prevalence of the plague, give not a single reference to a death. The writer's experience, having lived on a Scottish farm in his youth, was that feeding cattle, bought in the fall market, usually brought the infection with them, passed through the attack in the first fortnight and recovered without excep tion,. and that the next spring crop of calves lived and throve without any sign of the mal ady, even in cases of neglect of disinfection. The infection became inert when dried for 24 hours at F., but remained virulent for nine months when kept at 32° F. (Loffier). It in fected men who consumed butter and cheese from infected herds; others have eaten this without harm, but these were in infected dis tricts and the experimenters were veterinarians with ample previous opportunity for exposure to the disease and consequent immunization. It should be added that the outbreak of 1870, imported in English cattle landed at Levis (Quebec), which spread through Quebec, On tario, New York and New England, showing its virulence by sparing no bovine in any herd it entered, and extending to swine, sheep and human beings as well on the farm, ran its usual Old World course of two weeks, then subsided for lack of susceptible subjects, and, on the coming of spring and the fresh crop of calves, it failed to attack any one of these. There had been no killing, not even an official quarantine; only the owners secluded the stock as usual in winter quarters, and this allowed time for the spontaneous death of the germ. Again, the New England outbreak of 1902 from contaminated cowpox virus occurred, like the Quebec one, in the fall, and should have had an equal chance of dying out quickly but for the fact that it involved a number of large dairies supplying milk to Boston and other big cities and that it was officially subjected to compulsory slaughter, so that dairymen at tempted to hide the existence of the malady as far as possible to prevent the ruin of their milk business, their chief or only source of livelihood. The animals were huddled in close, unsanitary quarters, too often along with con cealed manure, and thus contracted secondary diseases from septic infection of the sores, which rendered the affection much more com plex and injurious. The outbreak and these
results lasted until May 1903, seven months after the Federal government took the matter in charge (or a year after the first circum stantial report of the existence of the pestilence in the State). This outbreak is in most marked and unhappy, contrast with the experience of the simple disease in Scotland, Canada, New York and New England in 1870; also with a number of more restricted outbreaks in which newly imported cattle were kept until they had passed through the disease and recovered.
Prevention, Exclusion.— For any disease like this, exclusively microbian, always requir ing importation to start the first case in any outbreak, non-fatal, lasting but two weeks, with microbe easily sterilized, the cheapest and most efficient resort is still to exclude it absolutely from the country by preventing importation. All warm-blooded animals must be shut out because these can contract the disease under favorable circumstances and can harbor the microbe causing the affection and convey it to other susceptible animals. This would of neces sity shut out not only warm-blooded animals, but also their products: hides, horns, hoofs, hair, wool, bristles, feathers, down, bones, meats, dried muscles, tendons, sausage cases, extracts of all kinds made from such animals, wet or dry, blood, virus, bacterins, miscalled vaccines, real vaccine (cowpox vari ola) and all other products that could convey foot and mouth disease. It would also exclude immigrants, and especially stock men, and those with soiled clothes until these were sterilized by heat. This is confessedly a large order, but we have already suffered through these chan nels and are liable to suffer again and again while present methods continue. Which then is better: to make our own products at home, or to stamp out every few years a pestilence threatening all of our 90,000,000 head of cattle that it can reach, and their yearly offspring, until the pest is thoroughly extirpated? An alternative would be to detain all such im ported animals and animal products at the port of arrival, quarantining the former under the most rigid and inflexible rules for one month, or more if needed, under constant pro fessional supervision; and sterilizing the latter by heat or by thorough disinfection before they were released. The mere exclusion of live imported cattle or their safe seclusion after arrival would be open to continual accidents and loophole escapes. Birds, insects and even vermin would open the way for escape of in fection. The efficacy of a perfect quarantine and disinfection was evidently recognized by the Federal officials, who, under the urgent protest of the owners of thoroughbreds then on exhibition in the Chicago International Cattle Show, retained the whole exhibit for a length of time and after disinfection finally released them. But inconsistently enough a highly valued thoroughbred herd outside the city was ruthlessly slaughtered; and again, when the Chicago Stock Yards were closed, several days' grace were allowed so that stock unexpectedly caught there could be disposed of. As might be expected the disease made its way in several new directions in the interval.
A costly and irremediable result of the slaughter of some of the best stock in the country lay in the sudden removal of priceless cattle that it had cost lifetimes to secure and the rendering impossible of the birth of their equally priceless prospective issue. It was a deed that 'could in no way be claimed as wise foresight, loyal patriotism nor devotion to the interests of live stock improvement or national prosperity. Official reports of cattle killed and paid for (1902-03) in the New England in vasion were $179,572.37. For that of 1908 re ferred to above the charges for cattle killed were $376,785.39, but these do not take into account the other losses to the stock owners, the interruptions, often permanent, of business connections and enterprises, the outlays made imperative to establish new lines of trade, the losses incident to restocking (when the old stock could have been profitably retained) and the certain loss of all prospective issue of the stock needlessly killed. The officials have sought to excuse their actions by quotations of heavy losses in dairy cows kept day and night in close, offensive city stables, the empty stalls being promptly filled from city markets charged with and again of others from Ger many, where, in addition, every city maintained its Freibank for the sale of defective meat at a cheap rate, and through which there was inevitably a continuous distribution of infection.