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112
Annual Report of the London County Council, 1910.
farriers and ostler); one was a carman's wife and lived adjoining the stables; one, a greengrocer,
had stables at the back of his premises; one, a window cleaner, lodged with a carman; one was a
case of laboratory infection; and one only had no connection with horses.
But many men work amongst horses and comparatively few get glanders, and it is well known
that knackers, who cut up, without any very special precautions, glandrous carcases, rarely get infected.
Some species of animals are immune to glanders (e.g., sheep and ox), and indeed the disease especially
affects the equine family; it is probable that man is much more immune to infection than the horse,
but much less so than the sheep.
Study of glanders clearly shows that marked contrasts are presented by the human and equine
diseases, so-called.
(i.) In origin. In the horse, cutaneous or subcutaneous inoculation is rarely mentioned in the
literature; the rival theories, there mainly referred to, are those of ingestion and of inhalation. In
human glanders inoculation from the skin of the exposed parts of the body occurs in more than half
the cases (Robins). Sir John Macfadyean has remarked that if inhalation played any considerable
part in transmission of the disease from horse to horse, it would have been expected to render the
glandered horse a source of great danger to man, and yet there is "the comparative rarity of glanders
among grooms and others working in badly infested glanders stables." Again, in equine glanders,
as Sir John Macfadyean says, "the carcase in general, and the blood in particular, are usually not
infective, the bacilli being almost entirely confined to the lesions and the discharges from them."
Thus, he says, "The living glandered horse is far more dangerous than the dead one, and the most
dangerous are those with profuse nasal discharge and the subjects of farcy." As he remarks, for
many years 800—2,000 glandered carcases have been dealt with in London by Messrs. Harrison,
Barber and Co., and during that period "no case of glanders has occurred among the men whom
they employ in this work." On the other hand, Bulloch and Twort (Centralblatt für Bakt. Orig. Bd.
xxxix. Heft. 1) insist upon the fact that serious risk is incurred by those who are brought in contact
with human glanders, or with material of human origin, and they have been led to suggest "that
the bacillus is probably much more virulent from human than from equine sources."
(ii.) In the clinical course of the disease and in the nature of the lesions found post mortem.
The subject cannot be here treated in detail, but we may allude to one point of special interest, viz.,
the occurrence of intra-muscular abscesses. Robins ("A Study of Chronic Glanders in Man") says:
"Subcutaneous or intra-muscular abscesses are by far the most constant of all lesions in chronic
glanders." In the horse, we are told, such abscesses are rarely seen. We note, however (Loeffler
and Schiitz) that they may occur in experimentally induced glanders in the horse. It is, of course,
well known that diseases run very different courses in different animals, but the contrast presented in
human and equine glanders is far more striking than is the contrast, say, between the anthrax, or the
tuberculosis, of man and animals.
A more or less parallel case to that of human and equine glanders is, perhaps, that afforded
by the naturally acquired tuberculosis of man and some animals on the one hand, and experimentally
produced tuberculosis on the other. Whatever the aetiology of glanders in the horse may be, human
glanders is apparently in the majority of cases traceable to direct inoculation of infective material
derived from the horse.
Diagnosis.—Clinically, suspicion is aroused when conditions mentioned above are met with in
people associated with horses, but the true diagnosis comes now within the province of the bacteriologist,
and recent scientific researches have produced several methods of great accuracy. The methods
adopted are as follows:—
(1) Bacterioscopy, or the direct finding of typical bacilli in discharges from open abscesses or
ulcers—a difficult and uncertain procedure—or, in closed abscesses, where they are very
scanty.
(2) Cultures, resulting in the obtaining of a pure growth of bacteria with typical characters
on potato and glycerin-agar, in about 48 hours.
(3) Animal inoculation (with material from the lesions) into a guinea-pig, with resulting
typical glandrous lesions in a few days. This is of special value in open wounds, where there are
too many contaminating germs to allow of isolation of the specific bacilli with certainty by the other
methods
(4) Mallein inoculation—the injection of mallein derived from pure cultures of B. mallei, into
the patient. This is the method adopted throughout the country for diagnosing all cases of equine
glanders, and particularly serviceable for detecting latent or occult cases. It is analogous to the
method of detecting tuberculosis by inoculation with tuberculin. Where glandrous lesions exist, a
definite reaction occurs within about 24 hours, consisting of a more or less local swelling and tenderness
around the site of inoculation, and a rise of temperature through several degress with a return
to normal in two or three days. The local reaction in man is not so constant a feature as in horses
but in all cases where tried there has been a rise in temperature. On the other hand, in numerous
cases (including several of tuberculosis giving a tuberculin reaction), which later turned out to be
non-glandrous, mallein in doses of 10 to 15 minims was injected without producing any result, leading
to the inference that the method of diagnosis is at least a harmless one ("Human Glanders, with a
study of six cases." Bernstein and Carling, British Medical Journal, 1909). In doses of less than