Microbial Diseases P. Pestis. Although This Material Is Antigenic in Laboratory Animals
Microbial Diseases P. Pestis. Although This Material Is Antigenic in Laboratory Animals and antibodies may be demonstrated in the sera of patients recovered from the plague, its role in the pathogenesis of plague has not been established. Clinical Manifestations. within a few hours of onset, and the patient has the general appearance of profound illness, with a flushed face and anxious expression. Bubonic Plague. the onset of symptoms.
The case fatality in untreated bubonic plague is variously estimated at 60 to 90 percent. Regional lymphadenopathy or buboes of flea-borne plague are found in the groin in more than 50 percent of patients with this form of the disease. Within a few hours, there is peri adenitis with edema of surrounding tissue. Buboes may involute slowly or suppurate with the discharge of necrotic material in patients who survive the acute phase of infection. Plague Pneumonia. Plague pneumonia ac-quired as a result of the respiratory spread of P. Headache and ag, the idea may be the early phases of illness, the paucity of signs is disproportionate to the obvious severity of the infection.
The cough may be absent until six or more hours have passed. Subjective symptoms referable to the chest may be absent, or the patient may complain of pleural pain or dull substernal oppression. The general clinical state has rapidly deteriorated, and patients with this disease are gravely ill after 10 to 15 hours of fever. Bloody, frothy, liquid sputum typical of plague pneumonia is produced in large quantities late in the disease at a time when the prognosis is uniform. poor. Laboratory Findings. There is an elevation of the erythrocyte sedimentation rate, but other hematologic abnormalities have not been observed.
A smear of the heart's blood of these animals will reveal numerous bipolar stain-ing rods. In all instances, however, a tentative diagnosis of plague must be made on clinical and epidemiologic grounds, there being dire consequences of a missed diagnosis, especially of plague pneumonia. on the judgment of this examination. Stained smears from organs of cadavers in cases of sudden death in plague endemic areas should be examined with great diligence to avoid the catastrophic spread of this disease.
Patients recovering from plague develop specific antibodies that may be demonstrated in convalescent-phase serum by bacterial agglutination, agglutination of erythrocytes sensitized with capsular antigen, complement-fixation, and mouse protection tests.