on. In
some instances the wind-pipe is primarily attacked, but when the disease
affects this part of the throat it is generally a consequence of the
extension of the membrane downward from the region of the tonsils. In the
former case the diagnosis is somewhat difficult, as cultures taken from
the throat may not show the presence of diphtheria bacilli, though
material that is coughed up may contain myriads of the germs; in this
phase of the disease interference with respiration is the symptom most to
be feared. The mucous membrane of the nose, eyes, ears and generative
organs, may be affected. Wounds are also liable to become infected with
this organism. In rare instances the membrane may extend down into the
bronchial tubes and lungs, and has been found on post-mortem examination
covering the inside of the stomach.

As complications we may have broncho-pneumonia, acute Bright's disease,
inflammation of the internal structures of the ears, bleeding from the
nose, inflammation of the valves of the heart, and sometimes paralysis of
this organ, with death; the last named sequel of diphtheria comes on
during convalescence, usually from two to four weeks after the subsidence
of local symptoms, and is due to inflammation of the nerves that control
the heart. Much less commonly paralytic conditions of the palate, throat,
eye muscles and the nerves of taste occur, and under rare conditions,
paralysis of the lower extremities. Paralysis of some kind follows in
from ten per cent. to fifteen per cent. of the cases, and appears with
equal frequency after the mildest as well as following the most severe
cases.

_Mode of Infection._--The germs of diphtheria may be carried in articles
used by persons with the disease, or they may be communicated by direct
contact. The micro-organism is found in the secretions from the mouth,
throat, or nose, and in particles of detached membrane. Bedding,
utensils, etc., used in the room where a patient has diphtheria, are
liable to carry the germs if taken from the sick-room, and consequently
should be always properly disinfected before being removed. Milk-bottles
carried into the sick-room, or handled by persons caring for the patient,
should never be returned to the dealer without being disinfected. Cats,
and less frequently dogs, may contract the disease and convey it to those
with whom they come in contact. Unrecognized mild cases are a frequent
means of spreading the disease, as also is a too e