The only constant and characteristic changes relate to the lymphatic system. The lymphatic glands were, as a rule, enlarged and deeply injected with blood. Where no buboes existed the glands of the various cavities of the body showed evidences of acute inflammatory processes. In some instances the affection of the glands appeared to be general; less frequently it was most conspicuous in, or apparently limited to, one or more great groups. Thus, the bronchial, the mediastinal, the mesenteric, the lumbar, etc. were severally the seat of marked changes with or without enlargement of superficial groups, or several of these groups were at the same time implicated.
In no instance were symmetrical enlargements of the inguinal regions, the axillæ, or the throat met with.
According to Runnel,10 in 2700 cases there were inguinal buboes in 1841, axillary in 569, maxillary in 231; inguinal buboes occurred 175 times on both sides, 729 times on the right only, 589 times on the left only; the axillary buboes were double 9 times, right only 185, left only 163. Buboes of the neck only occurred 130 times, and of them 67 cases were children.
10 A Treatise on the Plague, London, 1791.
The connective tissue surrounding the affected glands was the seat of an infiltration sometimes serous, sometimes cellular; it also very commonly contained more or less extensive extravasations of blood. Even where no buboes appeared on the surface of the body the glands were enlarged to twice their usual size or more. The substance of the glands in the larger swellings was at times uniformly red or violet, again whitish or marbled or pulpy or denser, or of the consistence of fat. It was also sometimes soft like jelly, and rarely it contained minute collections of pus. Some observers speak of dilatation of the lymph-vessels in the neighborhood of the enlarged glands.
DIAGNOSIS.—The difficulties attending the recognition of the plague at the beginning of an outbreak speedily subside. The rapid spread of the disease, its frightful mortality, the overwhelming intensity of the symptoms, the prompt occurrence of cases characterized by buboes, carbuncles, or petechiæ, are collectively considered diagnostic of this, and of no other disease whatever. In regions subject to the repeated visitations of this pest there exists a universal unwillingness to mention even the name of a disease whose suspected presence alone is followed by consequences of the most serious nature to the freedom of personal and commercial intercourse. To this unwillingness, rather than to any real likeness between the plague and other diseases with which it has been compared, are to be traced most of the difficulties as to the differential diagnosis that have been raised, especially in the regions bordering on the Mediterranean Sea.
It is not, therefore, necessary in this place to discuss the diagnosis between the plague and malarial and other pernicious fevers, malignant typhus, epidemic dysentery, lymphadenitis, syphilitic buboes, parotitis, and so forth.
TREATMENT.—Preventive.—The efficient treatment consists in prophylaxis. The history of this disease indicates with singular clearness the measures which, properly carried out, are capable of controlling the spread of the epidemic diseases. These measures arrange themselves into two groups, of which the first has to do with the removal of the conditions familiar to the development of the disease, the predisposing influences; and the second with the restriction of the disease to the locality in which it shows itself—isolation, quarantine.
The conditions favorable to the development of the plague have already been set forth under the heading Etiology. They relate to poverty and ignorance, and their attendant evils, in communities. They are those conditions which tend to disappear under the influences of civilization, and in truth it may be said that at the present time the plague occurs only in half-civilized countries.
Preventive medicine has achieved no other work comparing in magnitude and importance with the extinction of the plague in Europe. This was, to use the words of Hirsch, "a gradual process, and kept pace in great measure with the development and perfection of the quarantine system with reference to the Orient and the different countries of Europe." This author continues: "I cannot, in fact, understand how any one criticising the facts without prejudice, and having regard to the state of the plague in the East, can for a moment hesitate to attribute the chief cause of the disappearance of the plague from European soil to a well-regulated quarantine system." The European has by no means lost his susceptibility to the disease. He is liable to attack in the East. His protection at home lies in the restriction of the exciting cause of the disease to its present haunts.