515 
Foot-and-mouth disease, also known as “aphthous fever,'’ “epi- 
zootic aphtha,” and “ eczema contagiosa,” is an acute, highly infectious 
disease of cattle and other domestic animals the characteristic feature 
of which is the eruption of vesicles on the mucous membrane of the 
mouth and on the skin between the toes and above the hoofs. The 
vesicles rupture, forming erosions and ulcerations accompanied by 
salivation, great tenderness of the affected parts, loss of appetite, 
lameness, emaciation, and diminution in the quantity of milk secreted. 
In the early stages or in a mild attack of the disease the milk may 
present only a few abnormal characteristics, such as a fall in its spe- 
cific gravity to 1028-1025, and the reduction in the quantity of sugar 
and casein. When the disease is fully developed, or about the third 
da}q the milk invariably contains inflammatory products of a very 
pronounced character, and the quantity of milk secreted is greatly 
reduced. Cows affected with the malignant form of the disease lose 
practically all of their milk, but if the disease is mild in character the 
decrease will be from one-third to one-half of the usual yield. 
The milk becomes thinner, bluish, and poor in fat. Only in rare 
cases does the fat content increase with the diminution of the milk 
secretion. The casein and sugar content is reduced, but the salt con- 
tent is increased and the acidity diminished. If the udder becomes 
involved the milk has a slimy consistence and is yellowish and vis- 
cous like colostrum. It frequently contains coagulated fibrin and 
blood, so that a considerable sediment forms after standing, while the 
layer of cream which rises is thin and of a dirty color. Occasionally 
no layer of cream is formed, but the milk appears as a uniform, slimy 
mass of a bad odor, and a repulsive, rancid taste. This slimy con- 
sistence is due to the large quantity of albumen and globulin con- 
tained. The sediment contains leucocytes, desquamated epithelial, 
and broken-down tissue cells in large quantities, besides fibrin and red 
blood cells. 
This affection is transmissible to man through the ingestion of 
raw milk, buttermilk, butter, cheese, and whey from diseased animals, 
and also directly, though more rarely, from the saliva, secretions, or 
other infected material which may gain entrance through the abra- 
sions of the skin. Children are not infrequently infected by drinking 
unboiled milk during the periods in which the disease is prevalent in 
the neighborhood, while those persons in charge of diseased animals 
become infected through contact with the diseased parts as by milk- 
ing, slaughtering, or caring for them. In such cases the symptoms 
resemble those observed in animals. There is fever sometimes with 
vomiting, painful swallowing, heat and dryness of the mouth, followed 
b} T an eruption of vesicles on the buccal mucous membrane and very 
rarely b}^ similar ones on the fingers. These vesicles appear on the 
lips, gums, cheek, and edge of the tongue, and are about the size of a 
