In the Minden, hospital ship at Hong Kong, in 1843, when periodic fever and flux were prevalent and highly fatal, a man, convalescing from an attack of the latter, was suddenly seized with unquestionable symptoms of cholera, which ran its destructive course in a few hours. The case is noticed in the “Medical Notes on China,” as curious from its isolation; and a conjecture was hazarded at the time as to some affinity between its cause and that of fever and fluxes, then rife at that place. No other case of cholera appeared before or after it, though the subject was affected and died in the midst of a mass of men, accumulated between the decks of a ship.
A similar case occurred in the Rattlesnake, while employed in the West Indies, in 1826, with this difference, that it happened in a healthy ship to a healthy man. With incessant rice water vomiting and purging, rapid failure of circulatory power, lividity of surface, cold sweats, cold breath and tongue, the subject sunk in eighteen hours. No other case occurred in the ship, nor was another heard of on the station.
Whatever difficulty there may be in accounting for the occurrence of those cases of cholera, it can scarcely be imagined that they arose from human contagion. It is certain that the disease was not propagated by them.
In the year 1832, the north of Ayrshire generally suffered severely from cholera, while the south part of the county entirely escaped. The disease was excessively fatal in the county town—Ayr—situate about a mile north of the river Doon. It approached close to the north bank of the stream, but did not cross it. From that river to the river Stinchar, a distance of about 30 miles south, no case but one was known to exist; and that one occurred in a letter carrier who had been in Ayr, when, or immediately before he was attacked. He returned to his residence in Girvan, where he soon died with unequivocal symptoms of the disease which was raging in the town from which he came, but had not till then appeared in the town to which he returned. Yet with him the disease not only began, but terminated in Girvan—a poor place, in which the inhabitants are not remarkable for cleanly or orderly habits. Here then was a district extending 30 miles in one direction, by about 20 in the other, bounded on the north by the river Doon, on the west by the sea, on the south by the river Stinchar, and on the east by a chain of hills, where there was but one case of cholera, and that one carried into it, from a deeply affected place 20 miles distant. [17]
How was its immunity to be accounted for, if the disease which was destroying so many in Ayr was endowed with a contagious property? The intercourse was uninterrupted, and the district in question populous, containing many villages and considerable towns, including Girvan, with a population of about 5,000, mostly hand-loom weavers, a great majority of whom lived in crowded, ill-ventilated, ill-kept rooms. Cholera was carried there: the place and persons seemed especially fitted to foster and extend a contagious disease; yet the disease made no way there.
These instances, and hundreds of similar import which might be cited, seem to show that cholera is not primarily and necessarily a self-propagating disease. The question, as to whether, when, and how it has contagious power grafted on it, is one of more difficult solution, in which it is not meant now to enter; but reference may be made briefly to some circumstances which have been alleged in proof of the contagious property of cholera—of power possessed by it, either originally belonging to, or engendered by it.
In the autumn of 1833, Beith, a considerable town in the north of Ayrshire, was suddenly affected by cholera, which, in a few days extended to many persons, and in a few weeks cut off a large proportion of its inhabitants. About the time that the disease broke out, a poor family had arrived from Glasgow, where cholera still lingered, where it had existed more than twelve months, and where during the previous year it had been prevalent and destructive. The poor family that went thence to Beith were not affected by cholera, nor was it shown that they had been in communication with choleral patients in Glasgow. All that was proved against them was the fact that they had lived in that city, and yet on them was charged the introduction of cholera into Beith, and indirectly the mortality which followed.
It is worthy of remark, in illustration, with many such cases, of the mysterious movements of the cause of cholera, that Beith in the preceding year had wholly escaped its power, while adjacent towns and villages with which it had constant intercourse were suffering severely from it. That Beith should evade the contagious power of cholera in 1832, when the disease was rife in its near neighbourhood, and fall under it in 1833, when there is no evidence of its being nearer than Glasgow in mitigated force and occurring rarely, is, to say the least, difficult to understand.
In the spring of this year a custom house officer who had been on board a foreign vessel in the Thames, in which were cases of cholera, was soon after attacked by the disease, and died at Gravesend. A little later, a nurse who had attended a choleral patient in the Dreadnought Hospital ship was attacked by the disease and died. [19]
These two cases have been considered by some as all but decisive of the question; they have been looked on as furnishing cumulative proof of the self-propagating power of cholera. But to satisfy others, especially those gifted with only a moderate share of credulity, it would be necessary to show that there was not at the time an endemic cause of cholera on the banks of the Thames, which, though then but sparingly developed, was capable of exciting the disease in persons strongly disposed to it, by previous disease, destitution, or other debilitating agents. It would be necessary to show that one of the laws of other febrile endemics, such as yellow fever, does not influence this, namely that when the essential cause is in much force it attacks persons, though with a certain relation to individual susceptibility, with various degrees, up to the least conceivable degree of it; while reversely, when the cause is little diffused or concentrated, only those who are especially disposed to it—only those who have excessive susceptibility, natural or acquired—constitutional disposition, or disposition from circumstances of life—suffer from it. It can scarcely be denied, that on such difference mainly, if not entirely depends the difference in the prevalence of many febrile endemics; in one instance causing many, in another few attacks; now leading to a sweeping epidemic, and then giving rise to a few cases, or to one case. It would, in short, be necessary to show that while we are trying to trace the disease from one person to another, its cause is not springing from under our feet, and mingling with the air we breathe; which in the cases in question would not be an easy task, seeing that the disease had much endemic extension both before and after their occurrence, and that for years sporadic cases have been reported in the same or neighbouring localities. Nor will the doubts left in the minds of some enquirers, after full consideration of those cases, and allowing them all the weight they deserve, be lessened by reflecting on those which happened in the Minden and Rattlesnake respectively.