Hens, ducks, pigeons. Local inflammation, fibrinous exudate,
concreting or becoming cheesy, necrotic, sloughy. Beneath the mucosa
red, raw; without epithelium, but excess of lymphoid cells, some only
muco-purulent, gravity varies. Grave cases inoculable on birds, mice,
rats and rabbits. Bacillus diptheriæ avium, morphology and biology.
Pathogenesis. Prevention: exclude germ; cleanliness; pure air; pure
food; pure water. Quarantine strange fowls, keep flocks apart, seclude
manure, segregate sick, disinfect. Treatment: Antiseptics; boric acid;
sublimate: ichthyol; silver nitrate. Infection to man.
A disease of the mouth, fauces, nose and eyes, associated with the
formation of false membranes, has been long recognized in birds (hens,
ducks, pigeons, etc.), and is known to bird-fanciers by the names of
roup, and diphtheria. The disease is characterized by the presence of a
local inflammation in patches, associated in the early stages, with a
free serous discharge, but, later, with the formation of white, or
grayish, fibrinous exudate, which may be at first firm and smooth, later
soft and cheese like, and still later in many cases more or less
necrotic and sloughing. In Dr. Moore’s experience this is more common on
the conjunctiva than on the nares or fauces. The interior of the eye was
not involved in the inflammation. Beneath the false membrane the mucosa
was devoid of epithelium and the underlying tissue was red, raw and
angry, bleeding readily when handled, and infiltrated with an excess of
lymphoid cells.
The lesions however were by no means constant. In some even of the fatal
cases, the exudate was merely muco-purulent, while in others the false
membrane was quite abundant.
The gravity of the affection also varies in different outbreaks or in
the same outbreak at different times. Sometimes it runs a very rapid and
fatal course, while at others it becomes chronic and comparatively
dormant and the great majority recover.
In its more virulent form it is readily inoculable on birds, mice, rats,
and rabbits, while the milder cases are not easily propagated in this
way.
The false membrane contains a variety of saprophytes, and among them the
pathogenic bacillus, which may be obtained in pure culture by
inoculating it on a rabbit or mouse. Emmerich believed this bacillus to
be identical with the Klebs-Löffler bacillus of diphtheria in man, but
Löffler recognizes it as essentially distinct.
The _bacillus diphtheriæ avium_ is 0.8 to 1.5μ long, by 0.8 to 1.2μ
broad. The ends are oval so that short specimens seem round. In bouillon
cultures they form chains or clumps. They stain in aniline dyes, most
deeply at the poles. Are not stained by Gram’s method. They are
non-motile, ærobic, grow in agar, and alkaline bouillon, but render the
latter acid in one or two days. Do not grow on peptone gelatine, nor
produce gas with sugars. Are killed in 5 minutes at 58° C. (137° F.).
Are killed by dryness in 24 hours, by sulphuric acid (0.25 ∶ 100) in 10
minutes, by lime water in 1 minute, and by sulphur fumes.
_Pathogenesis._ Eight rabbits inoculated subcutaneously with 0.1 cc. of
the bouillon culture died in 18 to 36 hours. Of several white and gray
mice inoculated only one died. Inoculations of mature hens subcutem and
on the nose had no effect. Inoculation of a six weeks old chicken caused
death in 4 days with bacilli in the liver and blood (Moore). Inoculation
of pigeons produced the disease (Löffler). It seems doubtful whether the
milder forms part with their virulence to birds, when cultivated
artificially, or whether a special susceptibility is required in order
to render the inoculation effective.
_Prevention._ Besides the general conditions of good hygiene,
cleanliness, pure air, and pure water, the strict exclusion of the germ
is the great desideratum. New fowls should not be taken into a flock,
when they show any indication of disease in the mouth, throat, nose or
eyes, nor when they come from a flock in which such signs of disease can
be found. When examination of the flock, from which they are sold,
cannot be made, the new fowls should be placed by themselves in
quarantine until proved sound. Sound flocks should not be allowed to
wander at large and mingle with the birds that are unsound, or open to
suspicion. Neither should they be allowed to come in contact with manure
from suspected poultry yards. If disease of air passages, mouth or eyes
appears, separate at once the diseased fowl, and sprinkle roost, house
and yard with dilute sulphuric acid, quicklime, or other disinfectant.
_Treatment._ Beside separation and disinfection the local use of
antiseptics to the surface divested of the false membrane gives the best
promise. Boric acid solution (4 ∶ 100) or sublimate solution (1 ∶ 5000)
may be applied to the eye. For the nose and mouth somewhat stronger
applications may be made.
_Prevention of infection to man._ The essential difference of the
Klebs-Löffler bacillus of diphtheria in man, and the microbe of this
affection in fowls does not exclude the necessity of avoiding contagion
from birds to man. Among reported cases of such infection are: (1) That
at Wesselhausen, where 4 attendants on the fowls contracted the disease
from the sick fowls at a time when no other cases existed in the human
population: (2) That of Sebdon where 6 persons suffered and 10 fowls fed
by a hospital attendant also suffered: (3) That of Tunnis in which
diphtheria prevailed in fowls, and soon also in those who fed them
producing an extended epidemic: (4) That of Jacksonville, Ill., where a
diphtheritic chicken, conveyed the disease, with fatal effect, to a
child which fondled it (Moore).
These and other similar instances seem to show that the disease of the
bird may become so virulent as to be communicated to man, and the
disease of man so potent as to be transmissible to the bird. Every
precaution therefore should be taken to prevent infection passing from
one to the other.