The course of the attack may, for convenience of description, be divided into four stages: 1, the stage of invasion; 2, the stage of intense fever; 3, the stage of fully-developed localizations; and 4, the stage of convalescence.7
7 This formal division of the description is suggested in some of the older accounts. (See "Loimologia; or, An Historical Account of the Plague in London in 1665, by Nathan Hodges, M.D., and Fellow of the College of Physicians, who resided in the City all that Time, Lond., 1721.")
The appearance of the plague in France in 1720 was the occasion of a great number of curious and interesting publications on this subject.
1. The stage of invasion is marked by a feeling of lassitude, by pains in the loins and extremities. There is extreme bodily and mental weakness, headache, fulness and throbbing of the head, dizziness. The patient's expression is dull, stupid; he replies to questions slowly or awkwardly, his face is pale, his eyes languid, his gait feeble and staggering. The appearance in this stage has been compared by several observers to that of a drunken man. Shivering occurs, but if fever be present it is slight. Nausea, vomiting, and diarrhoea are symptoms sometimes observed. This stage begins suddenly. It is often imperfectly developed, and it may last only a few hours or a day or two.
2. The second stage is characterized by fever of the most intense kind. It is ushered in by a chill, sometimes slight, commonly severe. The lassitude continues, the headache increases, the dulness deepens to stupor or gives way to delirium. The temperature rises to 102°-104° F., or even to 107.6° F. The pulse quickly mounts to 120 or 130. The skin is hot and dry; the patient complains of burning inward heat and of great, sometimes unbearable, thirst. The eyes are sunken and injected; the tongue moist, pale, and thickly covered with a chalk-white or grayish pasty coating; the vomiting often continues. The delirium is commonly active or noisy, and accompanied by great restlessness; it may, however, be mild, tending to sopor or coma. The progress of the disease now rapidly advances. The patient falls into the so-called typhoid state. His tongue becomes dry, hard, and fissured; sordes collect upon the teeth and lips, bloody crusts about the nostrils. At this time the evidences of failure of the forces of the circulation become conspicuous. The pulse grows feeble, small, often irregular—sometimes it can scarcely be felt; the lips become bluish, the extremities cold. There is tendency to collapse. During the course of this stage buboes begin to make their appearance. Sometimes the enlargement of the superficial lymphatics is preceded by tenderness or pain of more or less intensity; often the glands are found to be enlarged only upon search.
The termination of this stage is marked by a sudden fall of the temperature to subnormal ranges (93.2° F. has been observed); at the same time copious strong-smelling sweat not infrequently occurs. The pulse grows feebler, and falls to 100 or below it, and the mind becomes clearer.
3. These changes lead up to the stage of fully-developed local manifestations. The enlarged lymphatics are most commonly situated in the groins or on the upper part of the thighs at a point below that commonly the seat of venereal buboes; less often they are to be found in the armpits or the region of the angle of the jaw; as a rule, they occupy only one or two of these positions in the same patient. They vary in size from a little mass or kernel, only to be discovered after careful search, to the bulk of a hen's egg or a mandarin orange. The swelling of the gland takes place at times with great rapidity. Suppuration is followed by the discharge of an ichorous pus, and not rarely by ulcerative destruction of the surrounding tissues. Suppuration occurs more frequently than resolution, but is comparatively rare in fatal cases. Hence it has come to be popularly regarded as a favorable prognostic sign, whilst the early subsidence of the swelling has been looked upon as an omen of grave import.
The time of the appearance of the buboes varies greatly. In the greater number of cases they have shown themselves on the second, third, or fourth day of the attack, occasionally within six or eight hours of the beginning of the attack, and occasionally they have been observed to precede the general manifestation of the disease; rarely they have appeared as late as the fifth day. In many cases they are absent altogether.
Carbuncles demand attention as being among the characteristic local manifestations of this stage. They are less common than buboes. Their usual position is upon the lower extremities, the buttocks, or the back of the neck. In favorable cases the gangrene after a few days becomes limited and the slough separates. Boils also occasionally appear.
Petechiæ occur in the worst cases, and often at an early period in the course of the disease. Their appearance usually indicates a fatal issue. They occupy at times extensive areas of the body or the greater part of its surface; at times they appear only in the neighborhood of the buboes. They vary in size from a mere speck to spots several lines in diameter. When very numerous they give a livid hue to the skin, and that appearance to the cadaver to which, together with the high mortality, was doubtless due the term black death by which severe epidemics were known in the Middle Ages.