“This is written of a time when the worst had not yet happened. It was about the beginning of September that the disease was at its height. Then fires were ordered to be burnt in the streets for three days together; but before the time had expired, they were extinguished by heavy rains, which ushered in the most fatal night of all with its register of more than 4,000 deaths.
“From this, its culminating point, the plague, ‘by leisurely degrees declined,’ ‘and before the number infected decreased, its malignity began to relax, insomuch that few died, and those chiefly such as were ill-managed.’ Dr. Hodges distinctly states that the pestilence did not stop for want of subjects, but from the nature of the distemper. ‘Its decrease was, like its beginning, moderate.’ Early in November, people grew more healthful, and though the funerals were still frequent, ‘yet many who had made most haste in retiring, made the most to return;’ ‘insomuch that in December, they crowded back as thick as they fled.’ The houses were again inhabited; the shops re-opened; the people went cheerfully to their work; the rooms, in which a short time before infected persons had breathed their last, were peopled afresh, and many went into their beds ‘before they were even cold or cleansed from the stench of the diseased.’ ‘They had the courage now to marry again,’ ‘and even women, before deemed barren, were said to prove prolific, so that, although the contagion had carried off, as some computed, about 100,000, after a few months, their loss was hardly discernable.’ But the next spring there appeared ‘some remains of the contagion,’ which was easily conquered by the physicians; and the whole malignity ceasing, the city returned to perfect health, as after the great fire, ‘a new city suddenly arose out of the ashes of the old, much better able to stand the like flames another time.’”
GEOGRAPHICAL DISTRIBUTION.
Plague is known in Europe, Asia and Africa, but it has not been known in the Western Hemisphere. It is said that Mesopotamia is the home of plague. It has been known as far North as Astrakhan in Asia and Norway in Europe. During the last fifty years, however, it is chiefly confined to Asia from Red Sea on one side, and the shores of the Pacific on the other. Some are inclined to think that the plague was carried from Himalyan India across Thibet to Yanon in Chinese territory, thence to Pekoi whence it made its way to Canton and Hongkong. If that be so, then the plague has accomplished a tour from Northern India viâ China by Sea route to Southern India within a period of twenty years between 1876 and 1896.
CAUSES—
A disease so fatal in its nature and against which human power is so futile was in ancient times naturally attributed to wrath of the gods. Supernatural, astrological, and, in some instances, rationalistic causes were assigned to it. In the fourteenth century the College of Physicians of Paris ascribed it to the influence of constellations in India. But more natural explanations, however, gradually followed. Putrefaction of dead animals was assigned as a cause in Egypt. Poisoning of water-supply was also believed to be the cause. Undue heat, rain, watery grain, and absence of the Etesian winds were thought to generate plague. Leaving ancient theories on the causation of the disease we find that modern Scientists divide themselves into two classes: first, those who believe in the germ theory and attribute the plague to a specific germ, holding that germs can never arise de novo; second, those who believe that atmospheric changes and certain telluric conditions or insanitary surroundings engender the seeds of pestilence which are carried through air, water or other media. The arguments in favour of the first theory are, however, so strong and overwhelming, that it is now almost universally accepted that plague is due to a specific poison which grows and multiplies under favourable conditions, and that wherever it occurs it is caused by the implantation of those germs in a suitable soil. If the soil is not fit, the germs may be sown, but they will not germinate and, if the soil is fit but the germs are absent, the disease will not be seen. The soil best suited for the plague seed is one where insanitary conditions prevail. Dirt and filth, bad ventilation, and overcrowding are its manure. The history of plague from ancient times fully illustrates that plague thrives in dirt, filth, squalor and misery. Diseased grain and want of subsoil drainage are held to be potent factors in the diffusion of plague.
BACILLUS—
During the Hongkong epidemic the great Japanese bacteriologist Kitasato, who formerly worked with Koch in Germany, discovered a bacillus in plague-stricken patients, and showed by experiments that these bacilli if injected into lower animals produced in them symptoms of plague. Yersin simultaneously discovered the same germs in connection with plague. According to our modern notion of the causation of the disease, these germs must be considered to be the specific poison which produces the symptoms of plague. The bacilli are found in the blood, in the buboes, and in all internal organs of the victim of the plague. They are short rods with rounded ends, with a clear space or band in the centre, readily stained by the aniline dyes and showing very little power of movement. The size of the plague bacillus varies, and bacilli of same character, but of less virulent nature, have been found in the soil of infected places. Some bacteriologists observed some development after death in the bacilli, this, if confirmed by observations at Bombay, will be highly interesting from a bacteriological point of view. If mice, rats, guinea-pigs and rabbits are inoculated with the plague bacillus, they soon become infected and die, and in their internal organs the same bacilli are found. They are also found in the soil and dust of houses where plague patients were kept, but not invariably so. Kitasato found the bacilli in the blood of patients convalescing from an attack of plague even three or four weeks after all symptoms have disappeared. It has been found that the bacillus dies after four days, during which it is kept at a dry heat, or at the temperature of 80°C. or 176°F. for half an hour, or at that of 100° C or 212°F. for a few minutes. Its resisting power to chemical disinfectants is feeble, dying in a 1 per cent. solution of carbolic acid or of lime water. It develops easily in many culture media at the ordinary temperature (from 18° to 22°C). An alkaline solution of Peptone 2 per cent., with from 1 to 2 per cent. of gelatine, is the best nutrient medium for its cultivation.
CONTAGIOUS AS WELL AS INFECTIOUS.
Experience has proved that plague can be transmitted from one person to another by direct contact; when a case of plague occurs in a house, other inmates of the house are much liable to be attacked also. Visitors to the house, medical and other attendants are also liable to be seized or to carry with them fresh focus of infection. It was, however, found in the Hongkong epidemic of 1894 that none of the European medical men, some fifteen in number, nor any of the Chinese students who were on duty at the plague hospital died. During the Egyptian epidemic of 1835 a French doctor, Bulard, with the courage of his conviction that plague was not contagious wore the shirt of a patient who died from plague, and yet did not contract the disease. Such immunity, however, was probably due to some circumstances which might be easily explained. In the Hongkong epidemic of 1894 three Japanese medical men contracted the disease, and in 1896, some European nurses were attacked. In Bombay the sad deaths of Surgeon-Major Manser and Miss Joyce prove that contagion plays an important part in the spread of the disease.