Popular Science Monthly/Volume 26/April 1885/Cholera III
| CHOLERA. |
By Dr. MAX VON PETTENKOFER,[1]
III.—MODES OF PROPAGATION {continued).
THE same considerations hold good in India. The famous places of pilgrimage, whose sanctuaries are annually visited by many millions of individuals, always have some cases of cholera among them; but it is only occasionally that an epidemic breaks out, and then it is only at those times when the predisposition to cholera exists—periods, be it noted, which do not for the most part coincide with the time when the number of pilgrims is at its greatest, nor when the principal feasts are in progress. For instance, Bryden has drawn up tables showing the number of admissions into the hospital at Puri in the neighborhood of the sanctuary called Jagganath for the years 1842 to 1866, and these statistics show the number of receptions of cases of cholera for each month of the year. This journal, extending over so many years, must give a good idea of the frequency of cholera in pilgrimage, even though the numbers be but small. The principal feasts, when the chariot of the deity is drawn over the breasts of the faithful, occur in the middle of March, but the period at which cholera is at its height is in June, when the number of pilgrims assembled is much smaller. Altogether there were three hundred and thirteen cases in March during twenty-five years, while the number was eleven hundred and fifty-five for June—or nearly four times as many admissions for cholera into the hospitals. Puri lies on the southwest border of the territory where cholera is endemic, and has the same rhythm so far as cholera is concerned as Madras. Hardwar lies in the northwest of India, where the chief feast occurs in April, the principal day being the 12th, and often hundreds of thousands of pilgrims, if not millions, stream together here; yet cholera only breaks out in an epidemic form when the regions are predisposed to it. It will be interesting to go further into detail on this question. Hardwar is situated about one thousand feet above the level of the sea, where the Ganges quits the Himalayas, and belongs to the holiest of places which the Hindoos worship. Cholera only occurs occasionally in an epidemic form. In the last century (1783) a severe epidemic was known to have occurred among the pilgrims at Hardwar. From 1858 to 1867 the feasts passed on without the occurrence of any epidemic of cholera, and this immunity was believed to be due to the soundness of the arrangements which were enforced by the Government. In 1867 the whole prophylactic armor was thrown aside. But already in November, 1866, an epidemic of cholera was approaching the neighborhood of Hardwar from Agra. The pilgrims began to arrive at Hardwar on April 1st. On April 3d the majority had assembled, although the stream of pilgrims continued to increase till the 12th. The whole number of pilgrims reached about three million. On April 9th the first case of cholera was detected by Dr. Kindall, and taken into hospital. Other cases soon followed. On April 12th, on holy-day, the pilgrims bathed from sunrise to sunset in the Ganges, in a holy fort which is separated from the torrent of the river by a rail, so that the people could not be drowned. Through this fort there was an incessant movement of men all day long. The water became thick and muddy, partly from the ashes of the dead which the pilgrims had brought with them to strew in the stream, and partly from the washing of the clothes and persons of the bathers. Every time a pilgrim entered the holy fort he dipped himself three times under, drinking the water and saying his prayers. The drinking of the water was never forgotten; if two or more members of a family bathed together, each one drank from the palm of another's hand. All these things happened every year for eight years without ill consequences. But in 1867 a violent epidemic broke out among the pilgrims. Macnamara, a believer in contagium and in the drinking-water theory, speaks as follows: "On the night of April 11th and on the following day a severe storm burst upon the unsheltered multitude. Only those who know what a storm on the mountains in the tropics is can have any conception what a night of misery these three millions of people suffered on the open plains of Hardwar. This fall of rain must have washed the contents of the closets and the filth on the surface of the earth into the Ganges." And Macnamara believes that on April 12th the pilgrims drank cholera from the Ganges; but Macnamara is wrong. Granted that the storm had really washed the cholera-stools into the Ganges, then the stools must have remained either in the river itself or else in the holy fort, just as was the case in Koch's water-tank. It is true I can find no numerical observations concerning the rapidity of the flow of the Ganges in Hardwar; but if we suppose that its i-ate is like that of the Seine in Paris at low water—i. e., half a foot per second—then the water would move at the rate of 1,800 feet an hour. The railed-off fort in which the pilgrims bathed is 650 feet long by thirty feet wide, and if the bathing lasted twelve hours, and if only a third part of the pilgrims had bathed, then more than 83,000 persons must have hourly passed through the water; this was impossible, so that only a small proportion of the pilgrims could have bathed on April 12th. These places of pilgrimage are also colossal markets and great places of business. It does not support the drinking-water theory to assume that, during the bathing of the 12th, cholera bacilli did not get into the holy fort from cases of cholera which would hardly be in a condition to bathe, but from cases of diarrhœa. Either a few of the bathers were, to start with, infected, and so large numbers could not be infected until the bacilli had become distributed, or, if a large number were infected at the outset, we naturally inquire where the infection was taken, and whether there was no possibility of their having been infected before going to the bath. While I do not believe that the pilgrims drank death from the holy stream, yet I shall not maintain that the stormy weather had nothing to do with the cause of the epidemic. Cases of this kind have occurred outside India, as in Malta and Spezia in Italy, v/here a sudden storm has sent up the death-rate in an explosive fashion. But if a weather-storm can create a "cholera-storm," then the cholera must be existent in the soil. One is reminded by this invasion of cholera of the clouds of dust which the watering-carts raise in summer. If the earth is very dry, the water not only lays but makes dust. I can conceive how a sudden heavy fall of rain may rapidly drive out the infective stuff contained in the soil. But Hardwar had experienced bad weather in other years on the same days in April without being followed by such evil consequences.
How does the journey of the pilgrim act in the spread of cholera? That infection can occur in a short space of time is witnessed in soldiers on the march. A case from Bryden's work may be quoted. In March, 1857, the Sixty-sixth Ghorka Regiment marched simultaneously in two divisions about seventy English miles apart, from the plains to the hill-stations along the Himalayan heights—the A division toward Almorah, the B toward Lohnghat—and both wings, though free from cholera at starting, became infected en route. The A division, 611 men strong, arrived on the 13th of March, free from cholera, at Tarai, a narrow strip of land between the plain of the Ganges and the Naini Valley. Tarai is notorious for its fevers and cholera, while the Naini Valley is celebrated for its general salubrity and its remarkable freedom from epidemics of cholera. The division left Tarai the morning after its arrival, passed into the healthful Naini Valley, and halted at the hill-station of Almorah. The first case of cholera showed itself in the Kaini Valley twenty-four hours after the first opportunity for infection. The first fatal case occurred on March 16th, two deaths occurred on the 17th, ten on the 18th, nine on the 19th and one on the 22d. These numbers show a mortality of nearly ten per cent. The B division was 361 strong, and passed through Tarai about a week after the A division, remained there but one day, and reached Lohnghat on the 23d of March. The first fatal case occurred on March 21st, while the division was still in Tarai; there were two fatal cases on the 22d, eighteen on the 24th, eight on the 25th, one on the 26th, and one on the 27th. Fatal cases thus occurred within a period of seven days. Such statistical facts, which might be multiplied, have as much value, as direct experiments, as infection through the linen of cases of cholera. It is strange, however, that most of the "cholera linen" first originated in the Naini Valley, in Almorah and Lohnghat where the disease did not spread further, and where certainly disinfection by carbolic acid or corrosive sublimate was not thought of. But the contagionists have no eyes for such facts. Just as was the case with the Ghorka regiments, so was it with the pilgrims at Hard war. On April 15th the great mass of the pilgrims—who had been quartered on a flat, partly marshy tract of land, about a square mile in extent, for several days—broke up and departed, so that a stream of 3,000,000 infected individuals for the most part, notwithstanding the influence of the bathing in the Ganges, reeking with filth, began to spread abroad over all India. According to the contagionists, an epidemic of cholera ought to have broken out in every place to which the wandering pilgrims came. In my view, epidemics may break out only where the time and local conditions are favorable; and where these conditions do not exist an epidemic is impossible, as the case of the Ghorka regiments proved. Bryden expresses himself in the following terms on the Hardwar cholera: "From all accounts which have been written concerning the outbreak at Hardwar, the impression is gathered that the epidemic was by no means a typical one. That is only the case, however, if the facts are considered in the light of preconceived theory. For those who search the statistics the facts come out in their true light, and prove that the type of an epidemic has nothing to do with the smallness or largeness of the number of people affected. The suppression of the cholera at Hardwar toward the east and south and the increase of it in the west and southwest are inexplicable phenomena [Bryden ought to have said, for the contagionists]. But the phenomena are not difficult to understand if the preconceived theory be laid aside. If we take Hardwar as the central point at which the gathering on April 12th was infected, then it will be found that the pilgrims died only in those districts which were reached within a limited time after their daily march had begun. The great majority of fatal cases did not occur at Hardwar, but in those regions which were reached within the first few days after leaving Hardwar. It seems to me that the end of the outbreak at Hardwar was pretty much the same as that of local outbreaks elsewhere, and I can see no connection between the epidemic of cholera in the Punjaub in May and the return home of the pilgrims." The movement the cholera had taken in the autumn of 1866 led Bryden to say, "I believe that the geographical distribution of cholera in 1867 would not have been very different, even supposing that the gathering of the pilgrims had never taken place." And Bryden is perfectly right, for in 1862, for example, the cholera in India became remarkably widely spread without cholera having broken out among the pilgrims at Hardwar.
Such epidemiological facts, which cry aloud for the truth of the existence of local and time predisposition, stand as sure, as etiological elements, as the discovery of a microscopic organism in the intestines of cholera-patients. Only ignorance and prejudice can ignore such facts. It is but a necessary logical conclusion that the comma bacillus, if it have anything to do with the infective material of cholera, must also have some relationship with the local and time conditions which favor cholera. And, further, the relationship must be discovered by the bacteriologists before they can explain an epidemic by the aid of their bacilli and before practical rules can be framed thereon.
Another objection to the views of the contagionists is found in the behavior of cholera on board ships. Long before I announced my views on local conditions, the epidemics of cholera, not only on the rocks of Malta and Gibraltar, but also on ships, were brought as witnesses against my doctrines. What can soil and ground-water have to do with epidemics on ships? And although I had found nothing but confirmatory evidence of my views, still the contagionists remained obdurate. As I can not suppose that all my readers are sufficiently acquainted with my observations on cholera in ships, I must be allowed to give a few illustrations. The contagionists, referring to cases in which epidemics occur during the voyage from Europe and America, say that such can only be explained on the view of infection of one case from another. The facts of such epidemic outbreaks are known to all. How often do such attacks occur? As an instance, I shall refer to the intercommunication between New York and Europe in the year of cholera, 1873. In that year, according to the register of the offices at New York, there were 700 vessels which arrived from different parts of the world, giving an aggregate of 316,956 individuals, but of these 266,055 came from Europe. Of these, 113,920 came from England, which was free from cholera; from the remainder of Europe the numbers were 152,135, and about 400 vessels served to convey the individuals, making up the last figures, from ports infected with cholera. If we inquire into the statistics, we find that cholera chiefly occurred on four vessels only. Eleven cases were registered from the Westphalia; one fatal case from the Ville du Havre; from the Washington three fatal cases; and from the Holland one fatal case.
Although the chances of contagion aboard ship are very favorable, yet how small was the number of cases of cholera! Take the ship with eleven cases, and we find that they belonged to two German families only; two died during the voyage, nine were landed on Dix Island, and of these but one died and the rest recovered. How is it conceivable that cholera should have confined itself to two families without attacking others? I believe that both families had contracted cholera before going on board; indeed, an epidemic may occur in a ship provided the passengers have all come from a place where cholera exists. The contagionists have, however, replied that some remarkable epidemics have happened on board ship, which could not be explained on the above-mentioned view. It is a question whether cholera can infect on board ship. The contagionists take facts conveniently; they select those instances which occur least frequently and adopt them, to the exclusion of the great majority of instances which tells against them. I recall the articles which I wrote in the "Vierteljahresschrift für öffentliche Gesundheitspflege" and in the "Zeitschrift für Biologie" to prove that I have thoroughly investigated the nature of epidemics of cholera on ships. Rumors of false returns concerning cholera on board ship have been bruited. But these falsifications can hardly be committed when an epidemic occurs during a voyage. It may be said that my instance of 1873 does not disprove the contagiousness of cholera. Cholera, like small-pox, does not attack every one who is brought into relationship with it. If even a few instances of contagion were proved to have occurred on board ship, we should have to admit the contagiousness of the disease.
I do not doubt that instances may exceptionally be found among infectious diseases in which the behavior is essentially the same as that of cholera on the ships going between Europe and New York. But the question is. How do such cases generally, not exceptionally, behave? Vaccinated persons maybe brought into contact with cases of small-pox without fear of infection; and, at times, individuals who have not been vaccinated may come in contact with small-pox without taking the disease. As a rule, however, small-pox on board ship behaves very differently from cholera. We shall pass in review an instance of a severe epidemic of cholera on board ship, notwithstanding that it favors the views and theories of the contagionists. The following specimen is chosen, for the reason that it occurred on a man-of-war, and as there are many such vessels the advantage of comparison exists: The Britannia was in the spring of 1852 equipped as an admiral's ship, and was generally stationed off Malta for the first year; in August, 1853, it went to Besika Bay, and in October to Constantinople, where it remained the whole winter; and, after the declaration of war, went in March, 1854, to Varna. With the exception of a brief expedition to Odessa and Sebastopol, it remained at Varna all through the summer. In August cholera broke out, and first of all among the troops on shore. The ship and the whole fleet were up to this time perfectly healthy. It was believed that the French had brought the cholera with them from the Dobrudja, whence some regiments had been sent from Varna. A few of these returned, but the majority met with their death either from cholera, typhus, or marsh-fever in the low country of the Danube. After the cholera had begun to subside on land it appeared in the fleet, among which it was, however, unequally distributed. At Varna there were assembled fifty-four ships-of-the-line, belonging to the English, French, and Turkish fleets, without reckoning the smaller craft. The Britannia lay, on August 20th, in the Bay of Cavarna, fifteen miles by water from Varna. About one hundred paces from it were lying two other English three-deckers, the Trafalgar and Queen, both, like the Britannia, manned by 1,040 sailors. The Britannia lost one hundred and thirty-nine from cholera, the Queen and Trafalgar four and six respectively. On the French and Turkish ships it was the same. Strange to say, the French admiral's ship, the Ville de Paris, like the Britannia, was most numerously affected; there were one hundred and sixty-two deaths, of which three were of officers. During the disease the French vessel lay at anchor off the coast with the rest of the fleet. The Britannia went to sea in the delusive hope of staying the course of the disease. That cholera should rage on the Britannia without causing the death of, or even attacking, one of the sixty officers on board, is for the contagionists an inexplicable circumstance. We must now inquire into the reason why cholera was so rife on the Britannia while the Trafalgar and the Queen were so mildly attacked. If the outbreak were due to the presence of cases of cholera, or to the linen from cases of cholera, on the ship, it might be urged that this circumstance was common to all the ships. Dr. Milroy has attempted to explain the epidemic on the notion that it was not due to the specific infective material, but to the individual predisposition to cholera. In the night it was found necessary, on account of the cases of diarrhœa and cholera, to close the hatchways on the lower decks while the ship was at sea. Dr. Milroy says: "The men appeared to be poisoned by the foul air which they had to breathe at night. . . . A more striking example of the deadly effects of impure air during the period of an epidemic, and of the most infallible means to check the evil, can not be imagined. The immunity of the officers was, on this occasion, unquestionably due to the greater space for breathing purposes which the officers enjoyed." That is an explanation which must satisfy the practical physician. I also believe that impure air is harmful, but I do not think impurity of air sufficient to explain such an explosion of cholera as that above referred to. It must not be forgotten that the Britannia went to sea on account of the general poverty of its hygiene. We ought to inquire into the condition of other ships also attacked with cholera, but in which the hatchways of the lower decks were not shut. My witness, who was on board the Britannia, assured me that the air was by no means so impure as Dr. Milroy made out. Another mistaken notion which I had taken up was also set right. I thought hitherto that the closing of the hatchways of the lower decks was occasioned by the stormy weather. On this point my informant writes to me thus: "The matter was not quite as you seemed to have imagined, and it will perhaps be best if I give a brief description of what actually took place. The day following our departure from Cavarna Bay a calm overtook us, and instead of the desired cool breeze a burning sun poured down on our sick ship. Then there came a swell on the waters, but no wind. In consequence the ship was so violently tossed that the hatchways of the lowest deck, where the crew slept, had to be closed, and then followed the worst night, during which fifty-eight men died, a night without wind, and without the slightest movement of the superheated air. Nothing was said of a storm. If we had but had one! That the shutting of the hatchways had any influence I do not believe; for, owing to the heat, the men were allowed to lie about where they pleased, and most of them betook themselves to the uppermost deck in the free air, and slept on the floor. The physicians had consented to this arrangement, and under the canopy of heaven the bulk of the fatal cases occurred. In this connection it must also be observed that the Ville de Paris, which did not go to sea, yet suffered as much as we did, in spite of the fact that the hatchways were not shut." So much for the explanation which regarded the shutting of the hatchways and the impurity of the air as the cause of the epidemic. The view of the contagionists meets with no better fate. That a cholera-patient should arrive on board with his stools or soiled linen explains nothing, since this circumstance was common to many other vessels without being followed by such consequences. If the infective material were brought in the food and drink on to the Britannia, how is it that only the crew and not the officers suffered? On this point my informant says: "Provisions came daily from the shore, even during the time we were fifteen miles away, but the officers ate the same meat, the same vegetables and fruit as the crew. The only difference was that the crew drank rum-and-water, while the officers had wine." Thus in the drinking-water no difference obtained. Ballast might have been a vehicle of infection, and for this purpose sea-sand and shingles, and other material, were taken from the shore. But I have been informed that "on the Britannia, as well as other English men-of-war, the ballast consisted only of so-called pig-iron, four-sided pieces, which were wedged together in the lowest part of the vessel, and never touched." We have yet to consider the different habits of the men and the officers while on shore before the outbreak of the epidemic. On this matter my informant writes: "The sufferers, not only of the Britannia, but of the rest of the ships of the fleet, had frequent communication by daily visits with the shore as we lay off Varna, and the crew without doubt betook themselves to those poisonous liquors, and still worse places of pleasure, which had sprung up on shore like mushrooms." It may be understood that the company of one ship would, like men of the same regiment, visit places of pleasure together and imbibe the same drink, and so it might happen that a particular crew visited a certain place where cholera prevailed, while other crews might have unconsciously kept clear of the places from which it is supposed cholera was taken. It remains doubtful whether the infection was derived through the air, water, or food. If these circumstances be viewed in an unprejudiced light, it will be seen that local conditions may account for the infection and spread of cholera on board ships. On emigrant-ships the matter can not be otherwise, and it is necessary, therefore, to inquire into the previous history of those who were taken ill on board. I have shown that the eleven cases of cholera which occurred on the Westphalia, bound for New York from Hamburg, came exclusively from two German families, and that an epidemic as vast as that which befell the crew of the Britannia might be explained, if we supposed that a majority of it came from the same district, or were placed under the same conditions as the two German families prior to their going on board. The exceptional outbreaks on emigrant-ships prove that such an occurrence is possible. That the Britannia, as a ship, was not a place of infection, is shown by the freedom from cholera enjoyed by the sixty officers. These points may possibly be cleared up by the appointment of a commission to inquire into the presence and etiological factors of cholera on board ship during epidemics of cholera. Koch has spoken of the occurrence of cholera on ships, and has attempted to reconcile matters on the basis of his doctrines of contagion. He has studied those ships which ply between North America and Calcutta. This line has not escaped my attention, and I have stated the main facts in my paper on "Cholera in India," 1871. Koch comes to the same conclusions as I did. Of two hundred and twenty-two vessels which made the voyage during ten years, cases of cholera only appeared on thirty-three ships, although they started from a district where cholera is endemic. It appeared to Koch only to be of importance, that cases of cholera continued to occur more than twenty days on sixteen ships; therefore these cases could not have originated at Calcutta, but must have been derived from infective material on board ship. If cholera is acquired from the infective material on board ship, how is it that the infective matter is, as a rule, so ineffective, and acts only exceptionally? If cholera lasts more than twenty days on board ship, then there must be other causes than those which prevail on land. Let it be assumed that the infective material proceeding: from human beings can call forth the disease after the third day and up to the twentieth day. Now, cases of cholera have occurred on board ship as long as forty days after leaving port, of which fact I could give many examples. But these are very exceptional. May it not be assumed that in such cases the infective material might be brought on board and kept effective in some form or other, and that individuals might constantly come in contact with the infecting agent? For exceptional circumstances exceptional causes must be assumed. Properly considered, it will be found that cholera behaves on ships pretty much the same as ague does. When ships leave a malarious district, cases of ague occur on board, but when farther out at sea they cease to occur. As a rule, the illnesses happen only in those individuals who come from shore, though exceptionally the disease shows itself in individuals who have never been ashore. But epidemics of ague have occurred on ships, as Hirsch has recorded in his work on "Malariakrankheiten," where the infection of the crew on shore appears to have been quite impossible, as on a ship which went from an Eastern seaport to England, and yet no one has ventured to say that ague is not dependent on the soil, or that it spreads on ships by contagion from man to man where the people have not been infected on land. The sweat of the sufferers from ague may be likened unto the stools of cholera-patients. If the infectious disease, ague, were as dangerous as cholera, it is not unlikely that many more observations on contagion from cases of fever, and on the presence of ague on ships, would have been made and recorded. Any exceptional occurrence in the way of ague on ships would almost certainly be more likely to be recorded if they happened on men-of-war or emigrant-ships than if they occurred on merchant-men, on the ground that the rare event is witnessed by a large number of men, and because the state of health of men-of-war and emigrant-ships is more carefully registered than is the case with smaller vessels.
- ↑ Reprint of a special translation made for the London "Lancet."