Geographical distribution: timbered lands in the United States;
different altitudes, and geological formations; on hills and wooded
bottoms; known to Indians and pioneers; now unknown where formerly
prevailed. Contagion: through milk; no specific microbe found in every
case. Alleged causes: rhus; nickel; spirillum; bacillus. Prevails in
dry seasons; contracted under night exposure; confined to given
enclosures; to late summer and autumn. Not conveyed by contagion,
indefinitely, as are plagues. Men show very varying susceptibility;
young children may be relatively immune. Fatigue, debility, ill
health, predispose. Exertion to fatigue rouses symptoms in animal
affected. Cow in full milk eliminates toxins and does not show
symptoms; the milk infects. Steers, bulls and heifers, show marked
symptoms. Calves suffer through milk; swine through veal; dogs through
pork; buzzard through dead dog. Incubation 8 to 12 days. Symptoms:
tardy, lazy gait, drooping, anorexia, ardent thirst, inactive bowels
and kidneys, milch cows when driven or excited, tremble and may
suddenly die. Muscular debility, constant decubitus, complete apathy,
neither evades nor resents injury. Bloodshot, fixed, glazed, unwinking
eyes, pulse and breathing slow, temperature low, hebetude, torpor,
coma; death 8th to 10th day. Sheep very prostrate. Calves tremble when
sucking, vomit and perhaps die suddenly. Pigs and dogs vomit, and show
costiveness, remarkable debility and weariness. Man is weary,
languorous, weak, apathetic, loathes food, is nauseated, retches. No
fever; but ardent thirst, tremulous tongue, mawkish breath, soft
flabby belly, careless of own or family interests, forgetful of
decency. Nausea, vomiting of blueish liquid, hebetude, inactive
bowels, coma. Lesions: gastro-intestinal congestions; ingesta like
hard balls of sawdust. Treatment: charcoal, mild laxatives, elm bark,
egg nog, potassium permanganate. Prevention: clear timber land, let in
sunshine, cultivate. Insects. Sterilize the milk.
This is an infectious disease which has been found enzoötic in certain
unimproved, timbered lands of North Carolina, Georgia, Tennessee,
Kentucky, W. Pennsylvania, Ohio, Michigan, Indiana and Illinois. Beach
says it has never been reported on any of the Western prairies, at any
point west of the Mississippi River, in New England, in the Canadas, in
any islands, or in any part of the Old World. Altitude appears to have
no effect in its production, nor geological formation; it has been found
in the wooded mountains of the Blue Ridge of N. Carolina and Georgia
(Kerr, Salmon, Phillips); in the hills of Pennsylvania and Kentucky;
(Beach, Phillips); on timbered uplands (Phillips); and on the wooded
bottoms of the Scioto and Miami in Ohio (Phillips, Schmidt); in the
timbered bottom lands of the Wabash and White Rivers in Indiana
(Phillips); and in the wooded bottoms (Beardsley), and Indian Grove in
McLean, Co., Ill. (Beach). The constant conditions are the heavily
timbered and virgin condition of the soil.
It was much more prevalent in the time of the early settlers, than it is
to-day, many infecting localities having become salubrious in connection
with the clearing away of the forests and cultivation of the soil. The
disease was well known to the Indians and often proved disastrous to the
pioneers, whole communities being swept off as recorded of Pigeon Creek,
by Nicolay and Hay in their History of Abraham Lincoln. According to
these writers it was “a malignant form of fever—attributed variously to
malaria, and to the eating of poisonous herbs by the cattle—attacking
cattle as well as human beings, attended with violent retching and a
burning sensation in the stomach, and often terminating fatally on the
third day.” Even in these early days settlers were loathe to acknowledge
the existence of the infection on their lands, doubtless because it
depreciated them, and to-day with a better knowledge of the necessary
precautionary measures, it has literally disappeared in many places, so
that it is now difficult to find a case.
_Contagion._ That the disease has been transmitted through the milk from
animals to man and other animals has been too painfully evident from the
first, but no specific microörganism has been found to be constantly
present, capable of pure culture in artificial media and of causing the
disease when transferred from such media to a new victim. Naturally all
sorts of theories have been advanced, no one of which has been
demonstrably proved. It has been attributed to eating of poison ivy
(Rhus toxicodendron) by the cattle, as this plant was usually found on
the infecting lands, but rhus is also common throughout New England and
the Eastern States where milk sickness is unknown. It has been claimed
that it was due to mineral agents, especially nickel, in the water but
the mineral salts in the water are not removed by culture of the surface
soil, which puts an end to milk sickness. Phillips (1876) claimed to
have found the cause in an actively motile spirillum in the blood, but
he had examined the blood of but one patient, and it has not been found
in other patients by subsequent observers. Bitting found a bacillus but
further research has not determined its constancy.
Beach furnishes a series of observations which should be useful in
seeking to estimate the value of any theory propounded. 1st. Milk
sickness is a disease of dry seasons. 2. In unusually dry seasons it is
dangerous to leave domestic animals out over night in the localities
where the disease is prevalent. 3d. It has never been considered
dangerous for animals to pasture on such lands in the day time. 4th.
Cattle in one field will habitually escape, and in another with
apparently exactly the same conditions and the same flora they are
attacked. 5th. The disease is unknown on the open prairies of the
Western States, where the domestic animals are not allowed to remain
over night in the timber belts. 6th. With occasional exceptions, it is a
disease of late summer and autumn. The dangerous lots can, as a rule, be
safely depastured in winter and spring. 7th. The pioneers found that
they could protect their stock by keeping them corralled on a “tame”
piece of land from before nightfall until the fogs and dews became
dissipated on the following morning.
For the land to become “tame” it was only considered necessary to cut
off the timber and let the sunshine act freely on the surface. Plowing
and cultivation did not seem to be requisite in all cases.
A great drawback to research is the difficulty of securing cases to
study. Many lots, formerly dangerous, are no longer so, and others still
infecting are kept so secluded that casual cases cannot be found,
without much expense for experimental animals. Again, owners do not care
to depreciate their land by acknowledging that it is infecting. The
experiment stations naturally enough look askance, on the proposal to
institute expensive experiments on a disease which dies out when the
soil is improved. Deadly as the disease is to the individual attacked
(man or beast), it is not propagated indefinitely from non-milking
subjects, by simple contact or proximity after the manner of plagues. It
usually comes to an end by the death or recovery of the subject that has
contracted it by consuming meat, milk, butter or cheese, the product of
an infected animal. The demand for sanitary police measures is,
therefore, less urgent. Different observers claim that cases occur in
the large cities, through the consumption of meat, butter or cheese,
sent from infected localities, but that the city physician fails to make
a correct diagnosis. These must, however, be comparatively rare.
In addition to ingestion as a cause, certain accessory causes ought to
be noted. Some men eat the infecting material with impunity, while
others succumb to the deadly disease. As the observations have all been
made in or near the infecting localities, individuals may be immune
through a previous attack and recovery, or there may be a native
immunity through unknown conditions. Young children often suffer less
than adults, possibly because of the greater activity of their
emunctories and consequent elimination of the toxic products and the
comparative absence of exhausting or depressing conditions. Their purely
animal food (milk) may exercise an influence, and this may assist in
explaining the fact that certain adults appear to be refractory.
Fatigue, debility and ill health are said to predispose the system. Milk
sickness attacks most violently those that have been subjected to
overwork or severe exertion of any kind, especially in hot weather,
those suffering from want of sleep (sitting up with the sick), those
having a special cause of mental depression, those suffering from some
illness—constipation, indigestion, malaria, etc.
Milch cows are probably more open to the attacks of the germ because
their systems are reduced by simultaneous milking and breeding through a
number of years. Exertion or fatigue has a potent influence in
developing the symptoms, so that it is a common practice in the vicinity
of infected localities to subject animals to a good run before
purchasing. Paradoxically enough the infected milch cow which is
distributing the infecting element freely in her dairy products usually
shows, in herself, no distinct symptoms of the disease. If she is dry or
farrow she suffers like any other animal, but if in full milk, the
toxins, and even the hypothetical microbe, seem to escape in that
secretion, which proves highly poisonous to other animals, while the cow
retains her spirits, vigor and outward appearance of health. Steers,
bulls and heifers, on the other hand, show violent symptoms.
Calves suffer so long as they suck the milk. The dead calf is eaten by
swine, which suffer in their turn, and the dog contracts the disease by
eating one of these animals, or by taking infected milk or cheese. The
buzzard eats the dead dog and dies as the result.
_Incubation_ is from 8 to 12 days, though it may be reduced to two.
(Beach.)
_Symptoms._ In the domestic animals the first indication of illness is a
lazy, tardy disposition, The subject stands apart from the herd, with
drooping head and ears, listless, indifferent to all around him, and
often without appetite; or, in cattle or sheep, rumination. There is
usually extreme thirst, but without correspondingly free urination or
defecation. Peristalsis is virtually abolished and nothing whatever
passes from the bowels. The patient is likely to be found lying down and
it is difficult to get him up, and when raised he moves stiffly and with
reluctance.
In milking cows there may be no symptoms until the animal is excited or
fatigued by violent or continued exercise, as a hard run, or a drive of
four or five miles. This developes the tremors alike in milch cows and
in the mild cases in dry cattle or sheep. The subject stands still and
trembles in a striking way, the action resembling the muscular
contractions seen after the removal of the hide in an animal newly
killed. The head and ears are drooped, movements are uncertain and
stiff, and the animal may even drop dead on the spot.
As the disease advances the muscular debility becomes so great that the
animal lies down if possible, and if once down he seldom rises again.
The decubitus is extended, the head being stretched on the ground. There
is a most complete apathy, the subject showing no fear, no apprehension,
no disposition to escape or resent injury. The wildest or most timid
steer can be freely handled, and there is no disposition to flight or
retaliation. The eyes are bloodshot and become fixed and glazed, winking
ceases, the breathing is slow, pulse infrequent, and temperature often
subnormal. The extremities and surface of the body are cool, the muzzle
dry, the coat usually stares, the apathy merges into a complete
hebetude, torpor and coma, in which condition the animal often dies on
the eighth or tenth day. Violent exercise precipitates the death at
once. Recoveries are infrequent and attended by no critical discharge
from bowels or kidneys, only by a slow, at first almost imperceptible,
resumption of natural action.
The milder cases, those that show no appreciable symptom when at rest,
are seized with trembling or rigor when made to undergo the slightest
exertion; they appear haggard, stupid and spiritless, drag their limbs
slowly and stiffly and quickly stop from pure weariness and debility.
The prostration is even more marked in _sheep_, which often seem unable
to rise, or lack the nervous energy to do so.
_Calves_ tremble while sucking, and will sometimes leave the teat, vomit
the contents of the stomach, fall down and perish.
In _Vomiting Animals_ (_pig_, _dog_,) emesis usually occurs, and torpor
of the bowels or obstinate constipation is present. _Pigs_ burrow under
the litter and are driven out with difficulty, and _dogs_ when called on
to follow, do so reluctantly, slowly and stiffly and fail to keep pace
with their master (“the Slows”).
In all animals alike active or continued exertion rouses or intensifies
the symptoms.
In _man_ there is at first extreme langour, weariness and weakness, the
patient cannot be troubled to move, he loses appetite, loathes food, and
soon has nausea and retching—often from the first. There is no chill,
rigor nor violent headache as in other fevers; but insatiable thirst;
large, flabby, tremulous, moist tongue, coated a dirty white; cold nose,
ears and general surface; dry skin; sweet, mawkish or offensive breath;
flat, flabby empty belly; without peristalsis or defecation. Respiration
becomes very slow, pulse weak and compressible, heart action tumultuous
and labored, temperature often below normal, and though sometimes 99° or
100° F., never higher. The patient takes to bed in four or five days,
or, after exertion or fatigue, in a few hours becomes profoundly
apathetic, expresses no concern for his business, his own future or that
of his family, is intolerant of bed clothes or other covering and
utterly oblivious of the demands of decency. Nausea continues, but
retching becomes weaker, and comparatively ineffective, or brings up a
little liquid which has been compared to blueing water of the laundry.
The apathy merges into a state of hebetude and this into coma, with
fixed, glazed eyes, absence of all winking, and insensibility to
irritants and death takes place quietly without a moan or struggle.
Recovery is slow, and improvement for a time is almost imperceptible. In
some cases there remains a nervous atony, and in man, a lack of mental
and bodily vigor, and a disposition to relapse under exposure to intense
heat or fatigue has been noted, but in many cases recovery is complete
and permanent without lasting weakness.
_Lesions._ Both in man and animals, congestions of the gastric and
intestinal mucosæ have been noted, usually with a dark firm condition of
the membrane, but in some cases with capillary stasis, and sloughing.
Beach never saw indication of tenderness in the abdomen or elsewhere,
nor did he ever find blood nor stercoraceous matter in the vomited
material. The contents of stomach (paunch in cattle) and bowels formed
hard balls like cemented sawdust, firmly adherent to the dry mucosa.
_Treatment and Prevention._ Treatment by the Indians consisted in giving
large doses of powdered charcoal suspended in milk. The early physicians
attempted to open the bowels by calomel and jalap, olive oil, magnesia
citrate, and even croton oil, but the last generally with fatal results.
Milder and hardly less effective treatment consisted in large doses of
elm bark. Beach believed he got better results with quinine and egg nog.
It might be suggested to try such antiseptics as potassium permanganate,
peristaltic stimulants like eserine or pilocarpin, as an eliminating
agent pure water or weak diuretics, and nerve stimulants nitroglycerine
or ammoniacal preparations.
_Prophylaxis._ The time-honored resort of clearing the timber and brush
land so as to let the sun act freely on the soil, and the putting in of
cultivated crops, is proved reliable and permanent. The other
precautions in use are valuable in protecting the herd, but lack the
merit of thoroughness and permanence and thus fail to strike at the root
of the trouble. They are: 1st. the exclusion of domestic animals from
the infected woods in late summer and autumn and in very dry seasons;
and 2d. the exclusion of stock from such pastures from before nightfall
until after the dews have evaporated on the following morning.
The danger which attends on passing the night in the forest, strongly
suggests the intervention for the transfer of the poison of some
nocturnal animal, perhaps a night-flying insect, like the anopheles,
which transmits the plasmodium of malaria. If the germ and its
intermediate bearer (if any) were demonstrated, probably other and
simpler means of prevention could be adopted.
The fact that the propagation of the disease is not constant and wide
spreading, like a genuine plague, lessens the urgency for a rigid
sanitary police, yet animals kept on such infected farms, should be
tested by long or vigorous driving before they are killed for food, and
all milk devoted to the production of butter and cheese should be
Pasteurized or sterilized before use. It might well be questioned
whether the clearing and exposure of infecting places should not be
undertaken by the state as a sanitary measure.
In view of the fact that a milch cow may not show symptoms of the
disease, and yet yield deadly milk, and considering that the owner
cannot always tell whether she has been in the infecting woods, or
having been in, whether she is infected, it becomes an important public
health question whether such a source of deadly disease should be
perpetuated, where human food is open to contamination.