when attempting to eat; in fact, the appetite is often so seriously
affected that all feed is refused, and the animal uneasily opens and shuts
its mouth with a characteristic smacking sound, while strings of cohesive,
ropy saliva hang suspended from the lips. With the advance of the disease
the vesicles widen and extend until they may reach a diameter ranging from
that of a dime to that of a silver dollar. These rupture soon after their
appearance, sometimes on the first day, more rarely on the second or third
day. After they have ruptured, the grayish-white membrane forming the
blister may remain attached for a day or more, or disappear speedily and
leave deeply reddened, sensitive spots or erosions, both within the mouth
and upon the coronet and between the claws of the feet. Similar erosions,
which quickly form scabs, as a rule, may be noticed in cases in which the
teats of milk cows have become affected, and instances are reported in
which sloughing of the tegument immediately around the lesions upon the
udder has occurred. Owing to the tough, fibrous nature of the bovine skin,
it is exceedingly rare for sloughing to occur upon any part of the body
other than those mentioned.
The attack upon the feet of an animal is frequently manifested in all four
feet at once, but one or more of the feet may entirely escape and remain
unaffected throughout the course of the disease. The ulceration of the
interdigital tissue may extend to the ligaments of the fetlock or produce
disease of the joint or bone. As the feet become sensitive and sore the
animal persistently lies down, and it has been found that bedsores develop
with amazing rapidity in all such cases and wholly baffle all attempts at
treatment until after the patient has regained its feet.
The disease may attack some of the internal organs before it appears upon
any of the external tissues. These cases are very liable to prove quickly
fatal. The animal dies from paralysis of the heart, due to the formation of
poisonous principles within the system; it may suffocate by reason of the
action of these same poisons upon the tissues of the lungs, or it may choke
to death as a result of paralysis of the throat.
In cases of serious affection of the udder the erosions will often be found
within the passages of the teats, resulting in a "caked" udder, and the
same toxic poisoning which is the cause of death in the apoplectiform types
just mentioned may arise from this source. In any event the milk from such
cases is dangerous for use, causing fatal diarrhea in sucking calves or
young pigs and serious illness in human consumers. The milk obtained from
cows suffering with foot-and-mouth disease is not readily converted into
either butter or cheese, but remains thick, slimy, and inert in spite of
churning and attempts at curdling. Pregnant animals may abort. In pigs,
sheep, and goats the lesions in the foot are most common, but both forms
may be observed or only the mouth lesions.
When the disease has become fully established it will be found that the
duration of the attack will vary greatly with different animals. From 10 to
20 days are usually required for the recovery of the normal appetite and
spirits in mild outbreaks, while the return to a full flow of milk, in the
case of milk cows, seldom occurs before the arrival of the following
season.
In the malignant type of the disease it requires from three months to a
year for an animal to recover. The mortality, as already stated, is usually
low. The disease is more fatal in young animals that have been fed on
infected milk, and produces death in from 60 to 80 per cent of these cases
as a result of gastroenteritis. In the 1914 outbreak numerous new centers
of infection started among hogs and calves which were fed on unpasteurized,
infected milk from creameries.
_Diagnosis._--The recognition of this affection should not, as a rule, be
difficult, especially when the disease is known to be in the vicinity; in
fact, the group of symptoms form a clinical picture too decided to be
doubted. The combination of high fever, vesicular inflammation of the
mouth, and hot, painful, swollen condition of the feet, followed 24 to 48
hours later by the appearance of numerous blisters varying in size from
that of a pea to that of a walnut on the udder and feet and in the mouth
should prevent any serious or long-continued error in the diagnosis;
however, in the inoculation of calves we have a certain and final test. In
24 to 96 hours after inoculation the calves present the characteristic
blisters. Such inoculation should be practiced, however, only by officials
properly authorized to deal with contagious diseases.
_Differential diagnosis._--The lesions of no other disease of cattle
closely simulate the vesicular eruption of foot-and-mouth disease on the
lining membrane of the mouth. When the blisters have ruptured, however, and
the resulting lesions have become contaminated by numerous secondary forms
of microorganisms, the correct recognition of the disease may be involved
in considerable difficulty.
Cowpox or horsepox may be accidentally transmitted by inoculation. But the
eruption of the "pox" goes on to the development of a pustule, while in
foot-and-mouth disease the eruption is never more than a vesicle, even
though the contained fluid may become turbid. The inoculation test in the
case of cowpox does not respond with fever and eruption for at least 10
days, and often longer.
Necrotic stomatitis (sore mouth due to a germ) may be distinguished from
foot-and-mouth disease by the fact that in the latter there is a rapid
infection of the entire herd, including the adult cattle, as well as the
infection of hogs and sheep. The characteristic lesion of foot-and-mouth
disease is the appearance of blisters containing a serous fluid upon the
mucous membrane of the mouth and upon the udder, teats, and feet of the
affected animals. In necrotic stomatitis blisters are never formed,
destruction of the tissues occurring from the beginning and being followed
by the formation of yellowish, cheesy patches, principally found involving
the lining membrane of the mouth, especially the tongue and cheeks.
In mycotic stomatitis (sore mouth due to a fungus or mold), portions of the
lining membrane become inflamed and in a few days it changes to a croupous
membrane which peels off, leaving a raw surface, while the thin skin
between the toes may also be inflamed. The previous history of the case;
the failure of the blisters, if any appear, to spread extensively; the
absence of vesicular eruptions on other portions of the body, notably the
udder and teats, and, characteristically, the hoof, together with the
absence of rapid spread to practically all cattle in the herd and the
complete negative character of inoculation of calves, distinguish between
the local disease named and foot-and-mouth disease. Mycotic stomatitis
occurs in only from 10 to 50 per cent of the animals in a herd, usually in
the late summer or early fall after a dry spell, and it does not run a
regular course.
The lesion, resulting from ergotism may be distinguished from those of
foot-and-mouth disease by the lack of eruptions in the mouth and by the
location of the disease at the tips of the ears, end of the tail, or upon
the lower part of the legs, usually below the knees or hocks. The lesion of
ergotism does not take the form of pustules or blisters, but manifests
itself first as a swelling about the ankle, which later may slough and
circumscribe the limb, forming a deep crack, extending entirely around the
limb and forming a distinct line of demarcation between the healthy skin
above and the diseased below. The absence of ulcerous sores on the coronet
and between the claws, together with the healthy condition of the membranes
of the mouth and the knowledge that the lesion upon the limb in question
extends uninterruptedly around it, should point conclusively to a diagnosis
of ergotism and to the exclusion of all fears of foot-and-mouth disease.
In foul foot or ground itch of cattle, the inflammation of the skin and
toes is general and not in certain spots, as in foot-and-mouth disease. The
mouth remains unaffected, and the presence of the disease may be traced to
filth and poor drainage.
The severer forms of the disease might be confounded with certain general
diseases. If gastrointestinal symptoms predominate, acute gastric catarrh
or inflammation of the intestines might be thought of. Involvement of the
lungs may lead to a diagnosis of acute congestion of the lungs or
pneumonia. The distinction is apparent in these diseases by the lack of
vesicular eruption on the mucous membrane or skin, and also by lack of
evidences of infection in the herd or neighboring animals.
_Prevention and eradication._--The measures to be adopted to prevent the
spread of the affection must take into consideration the highly infectious
nature of the disease, its ease of dissemination, and the liability of the
virus to live for long periods outside the body of an animal. Great care
should therefore be observed in keeping healthy animals unexposed to the
contagion. When an outbreak occurs in a community the owner should make
every effort to keep other animals from coming in contact with his diseased
cattle. This especially applies to dogs, cats, goats, and poultry, which
usually have access to the stables and barnyards and in this way furnish
excellent means for disseminating the infectious principle. He should be
equally particular in prohibiting any person from coming onto his premises,
especially an attendant or owner or other person in any way connected with
cattle. Such a herd may be placed under quarantine, with an inspector
appointed to keep the premises under constant surveillance.
This method of quarantine alone, while very satisfactory in many instances,
is rather tardy in obtaining the desired result. The experience of European
Governments already mentioned shows that eradication by this method alone,
when the disease has obtained a foothold, is practically impossible. For
this reason, when the disease breaks out in a country like the United
States, where the contagion is likely to spread rapidly by means of
infected cars, manure, hay, and other feed, and where the results of its
obtaining a firm foothold would be so disastrous, it seems that this method
of temporizing is rather tedious, and more radical steps are required in
order to suppress and eradicate completely the infection in the quickest
and most thorough manner possible.
It would therefore appear better, after judicious appraisement, to
concentrate the expense incident to the extermination of foot-and-mouth
disease by purchasing and slaughtering all affected and exposed cattle. The
carcasses of these animals should be totally destroyed, preferably by
cremation, or otherwise by burying them in a hole 6 feet deep and covering
them with air-slaked lime. The infected stable should be disinfected by
thoroughly cleaning it, scrubbing the floor with hot water, brushing down
all loose dust from the walls, and tearing off all woodwork which is partly
decayed. Then the whole interior of the stable should be disinfected with
one of the following substances:
A 5 per cent solution of pure carbolic acid.
Chlorid of lime, U. S. P. strength (30 per cent available chlorin), 1
pound to 3 gallons of water.
Formaldehyde, 1 quart 40 per cent solution to 5 gallons of water.
A 3 per cent solution of cresol compound, U. S. P., or accepted
substitute therefor, containing at least 50 per cent cresylic acid.
All stable utensils should be thoroughly cleaned and disinfected by the
application of a solution of one of the above-named disinfectants. The
manure should be burned or disinfected and spread over ground (other than
meadow land) that is to be turned under. No other cattle should be
purchased for at least sixty days after the complete disinfection of the
premises.
The success in eradicating the disease by combined quarantine, slaughter,
and disinfection, as practiced in the United States, Denmark, Great
Britain, and a few other countries, demonstrates in a striking manner the
efficacy of slaughtering and the futility of relying upon quarantine alone
to stamp out the disease.
Inoculation has been adopted in some countries in order to have the disease
spread quickly through the herds, and while this practice has undoubted
value where the disease is indigenous, it is not desirable in this country
and should not be adopted.
As a rule medicinal treatment with a view of curing affected animals is not
to be recommended under conditions prevailing in the United States, where
the disease has not become established, and the first object is to stamp it
out as quickly as possible. Even though most animals would recover, with or
without treatment, it would be practically impossible, while they were
being held for recovery, to prevent the spread of the infection to others.
The disease would be liable to spread faster than it could be cured. As
already pointed out, it has been found impossible to prevent absolutely the
spread of the contagion by the strictest quarantine alone, under the usual
farm conditions. In addition, the affected animals that have passed through
the disease may become a source of further infection as virus carriers for
weeks and months after they have apparently recovered, and are susceptible
of reinfection, as one attack does not confer permanent immunity.
_Foot-and-mouth disease in man._--Foot-and-mouth disease is primarily and
principally a disease of cattle; secondarily and casually, a disease of
man. It is transmissible to man through the eating or drinking of raw milk,
buttermilk, butter, cheese, and whey from animals suffering from
foot-and-mouth disease. It is also transmitted directly, though more
rarely, from the salivary secretions or other infected material which may
gain entrance through the mucous membrane of the mouth. It is doubtful
whether the disease can be transmitted to man by cutaneous or subcutaneous
inoculation, though it is probable that the infection may be communicated
if the virus directly enters the blood through wounds of any kind. Children
are not infrequently infected by drinking unboiled milk during the periods
in which the disease is prevalent in the neighborhood, while persons in
charge of diseased animals may become infected through contact with the
diseased parts or by milking, slaughtering, or caring for the animals.
The symptoms in man resemble those observed in animals. There is fever,
sometimes vomiting, painful swallowing, heat and dryness of the mouth,
followed by an eruption of vesicles on the mucous membrane of the mouth,
and very rarely by similar ones on the fingers. The vesicles appear on the
lips, gums, cheek, and edge of the tongue, and are about the size of a pea.
The vesicles soon rupture, leaving a small erosion which is soon covered by
a thin crust under which the new formation of epithelium proceeds rapidly.
The skin eruption mostly appears on the hands, tips of the fingers, base of
the nails, and more seldom on the toes and other parts of the body. Besides
these local changes, during the course of the disease headache, pain in the
limbs, vertigo, abdominal cramps, vomiting, diarrhea, and weakness are
occasionally observed. The disease is seldom fatal, usually appearing in a
very mild form except in weakened children, in whom an accompanying
intestinal catarrh may lead to a fatal termination.
Veterinarians who have had considerable experience with the disease among
animals regard the human affection as by no means uncommon in countries
where foot-and-mouth disease prevails, but the disturbance of health is
usually too slight to come to the notice of the family physician.
But few outbreaks of the disease in man have occurred in the United States,
and therefore cases of its transmission to man in this country are rather
rare. Dr. James Law reports having observed the disease in man from
drinking infected milk during the epizootic of 1870 in the Eastern States,
but the outbreaks of 1880 and 1884 affected such a small number of animals
and were so quickly suppressed that no instance of its transmission to man
was recorded. A few cases have been reported by Brush accompanying the New
England outbreak of 1902. Similar reports have been likewise received
concerning the appearance of vesicular eruptions in the mouths of children
during the 1908 and 1914 outbreaks, and the history of these cases
incriminates the milk supply.
Experiments by Loeffler and Froesch, as well as recent experiments which
have been made in Denmark and Germany, indicate that the infection is
comparatively easy to destroy by heat or the usual antiseptics. Milk
pasteurized at a temperature of 60∞ C. for 20 minutes is safe so far as
infection by foot-and-mouth disease is concerned.
SEPTICEMIA AND PYEMIA.
These two names are applied to diseased conditions which are so nearly
alike in their symptoms that it is sometimes difficult to distinguish the
one from the other. Indeed, the name pyosepticemia, or septicopyemia, is
often applied when it is impossible to make a distinction between
septicemia and pyemia or where each is equally responsible for the diseased
condition. The name septicemia is derived from two Greek words meaning
"poison" and "blood," and signifies that the germ lives in the blood, hence
the use of the term "blood poisoning" for this disease. Pyemia is likewise
derived from two Greek words, meaning "pus" and "blood," and is that form
of septicemia caused by pus-producing organisms and characterized by
secondary abscesses.
_Causes._--Neither of these diseases is brought about, strictly speaking,
by any specific organism; hence neither can be looked upon as a specific
disease. The organisms most frequently found in cases of septicemia are, on
the whole, the same as those of pyemia, and may be pus cocci, the bacillus
coli, or other pus-producing organisms. These organisms are often found as
secondary invaders in other diseases, such as advanced cases of
tuberculosis, in which cases they are responsible for the formation of pus.
Aside from the causative organism, or, in other words, the active cause,
there are many secondary causes. The most important of these in pyemia is a
break in continuity of the protective covering, as a wound, which affords
an entrance into the tissues for the organisms. Among the different
varieties of wounds may be mentioned cuts, bruises, punctures, burns,
chemical or frozen wounds, and compound fractures of bones. Injuries
received during parturition, stoppage of the milk ducts, and infection of
the umbilicus in the newly born are also frequent causes of pyemia.
Septicemia usually follows surgical wounds, local suppuration, enteritis,
bronchitis--in fact, wherever there is a local lesion of any kind
permitting germs to enter the blood. Septicemia was formerly applied to
designate the condition in which the organisms were localized, but in which
their toxins were diffused in the blood. Pyemia was made to represent that
condition when the organisms were localized, but in which the pus was
transported by the blood. These terms now are applied to conditions in
which both the organisms and their toxins, or the pus, are present in the
blood. The term septicemia is indicated when intoxication is the more
pronounced symptom and pyemia if pus formation and metastatic or secondary
abscess formation are observed.
_Symptoms._--The symptoms of both diseases include primarily a high fever
(104∞ to 107∞ F.). Coupled with this there is disinclination to move, the
animal is depressed and not cognizant of its surroundings. The pulse is
rapid, small, and feeble, respiration increased, mucous membrane injected,
swollen, and of a yellowish tinge. Appetite is lost and death follows in
the case of septicemia in from two to four days. In pyemia the symptoms
come on more slowly and are not so intense as in septicemia, while the
course of the disease is longer, lasting from six days to four weeks. The
mortality is not so great as in septicemia, but the period of convalescence
is always long.
_Lesions._--Septicemia is characterized by the destructive changes in the
blood, which is chocolate colored, noncoagulable, and swarms with bacteria.
The lining membranes of the heart are studded with red spots, often running
together to form a large hemorrhagic area. The lungs, liver, and kidneys
may also show these hemorrhages. The spleen is enlarged and full of black
blood. The cadaver decomposes very rapidly and in some cases forms great
quantities of fetid gas. In pyemia, in addition to these lesions, abscesses
are formed in the various organs throughout the body. If the disease
develops slowly a post-mortem examination shows the abscesses to be the
chief alterations. The pus content is usually greenish, stained with blood,
and contains strings of fibrous tissue and necrosed matter.
_Treatment._--Treatment is almost futile in advanced cases of either
disease. Septicemia is usually fatal and pyemia frequently so. Prevention
and the immediate treatment of local infections are the surest means of
combating them. For local treatment of wounds the usual antiseptics are
indicated, such as 3 per cent compound cresol or carbolic acid, or one
one-thousandth bichlorid-of-mercury solution. For pyemia, where the
abscesses are near the skin, they should be opened and treated
antiseptically by injecting any of the previously mentioned germicides.
General and heart stimulants are indicated, such as a drench containing
digitalis 2 drams and alcohol 2 ounces. Quinin and calomel in repeated
small doses of one-half dram each three times a day are sometimes
beneficial. Camphor in the form of oil of camphor (camphor dissolved in
10 parts of sweet oil) is a good stimulant and has some antiseptic
properties, which make it a valuable drug in combating these diseases
when it is given in doses of 2 drams three times daily.
HEMORRHAGIC SEPTICEMIA.
Hemorrhagic septicemia is a name applied to a highly fatal, infectious
disease existing in various species of domestic and wild animals, from a
microorganism having definite biological characters and possessing the
properties of producing clearly defined and characteristic lesions.
This causal agent, _Bacterium bovisepticum_, belongs to the same group of
cocco-bacilli as those causing chicken cholera, swine plague, and rabbit
septicemia, and may be described as an ovoid, nonmotile, polar-staining
bacterium with rounded ends, 1/38000 of an inch wide by 1/20000 of an inch
long, sometimes seen in pairs and sometimes in chains.
Various names have been applied to this disease, and though the causative
agent and the distinctive lesions are well known, it is more than likely
that the affection is seldom recognized. It was described by Bollinger in
1878, and named Wild und Rinderseuche, from its having affected deer, wild
boars, cattle, and horses in an epizootic which swept over Germany at that
time. Before this, however, several epizootics of what was evidently the
same disease had been well described, notably that which occurred in
England in 1854. Since then it has occurred in epizootic and enzootic forms
in many sections of Europe, Asia, Africa, and America. In this country the
disease has been observed in Texas, Tennessee, New York, Minnesota,
Pennsylvania, District of Columbia, South Dakota, and Wisconsin. Other
names given to it are game and cattle disease, buffalo disease, barbone,
pasteurellosis bovina, ghotwa, and infectious pneumoenteritis.
In earlier times it was evidently confounded with gloss anthrax, and even
now it is probably mistaken in a great many instances for anthrax,
blackleg, cornstalk disease, and cerebrospinal meningitis.