The history of the disease in Europe furnishes a multiplicity of similar cases, and even more distinctly exhibits the dissemination of cholera by contaminated water.11 In Holland not less than five epidemics of the disease occurred between 1832 and 1869, all of them causing a great mortality, to which the epidemic of 1866 alone contributed not less than 20,000 deaths. This was about 55 deaths for every 10,000 inhabitants. Such exceptional mortality over so wide a territory has been ascribed to the extreme porosity and humidity of the soil, which is nearly all below the level of the sea. Such a soil must necessarily retain longer than other soils whatever it absorbs, and thus tend to render the well-water habitually impure. If, then, to the ordinary impurities a specific poison is added, its characteristic effects may assuredly be looked for. The conditions now stated explain the conclusions of Ballot of Rotterdam, drawn from a study of the several epidemics referred to. They are as follows: "1. Holland is highly affected by the cholera at every epidemic, chiefly in those parts where they drink water directly from the rivers and canals or from ground saturated with sewage. 2. In places where rain-water is generally drunk the disease is far less violent. 3. Places where there is no other drinkable water but rain-water are not affected by the epidemic; the single cases occurring there are imported. 4. When places affected by the cholera were supplied with pure water instead of the vitiated water the disease disappeared."12 In like manner, we find that the cholera epidemic of 1873 in Germany seemed specially to select those situations where the subsoil was impregnated with decomposing organic matter; and it is evident that, in cities especially, such situations would include the most poverty-stricken districts, while the higher, drier, and at all times more salubrious localities are inhabited by the classes enjoying the greatest material prosperity.13
11 It is of interest to note that on the first appearance of cholera in England, at Sunderland, in 1831, a surgeon of that place, Mr. Ainsworth, collected and published conclusive proofs of the importation of the disease, of its communication from the sick to the well, "and of its propagation by clothes, and even by emanations, from the dead" (Observations on the Pestilential Cholera, London, 1832).
12 Med. Times and Gaz., May, 1869, p. 459; June, 1869, p. 626.
13 "Report of the German Imperial Commission," Practitioner, xxvi. 153.
This mode of infection has been traced in numberless individual cases of cholera. In London there was a certain well into which the liquid contents of a sewer had been percolating for months. Of the water of this well hundreds of persons had been drinking without obvious injury. At last a case of cholera occurred hard by; the discharges were thrown into a privy which communicated with the sewer and indirectly with the well, whereupon more than 500 persons who drank water drawn from that particular well were attacked with cholera within three days. So in 1856 cholera prevailed in the county jail of Oxford, Eng., the drain from which emptied into a pool from which the water was drawn to supply the city prison. In the latter institution cholera began to prevail, but declined as soon as the pipes conveying the water were cut off, and soon afterward ceased entirely.14 Again, in Constantinople in 1865 the clothes, mattrasses, etc. of cholera patients were washed at a fountain the basin of which was divided into two parts by a wall; one part was used for washing clothes and the other for drinking purposes. Unfortunately, the waste-pipe of the former being obstructed, the foul water of one side communicated with the clean water of the other, and in one day 60 people died of cholera in the small portion of the city which was supplied from the infected source. The striking case has often been cited which occurred at Epping, Eng., where a woman brought the disease from a distance into a perfectly healthy house and neighborhood, and of ten persons affected with it seven died, including a physician in attendance upon one of them. An examination of the premises "discovered, below the pipes leading from the water-closet and from the eye-hole of the sink through which the choleraic dejections had been passed, a leakage which extended under the foundations of the building and entered the well. The sewage was distinctly traceable on the side of the well corresponding with the leakage in the drain." After this discovery and the disuse of the foul water not another case occurred.15 In 1868, Dr. Farr, in his History of the London Cholera Epidemic of 1866, showed that water into which cholera dejections find their way produces cases of cholera all over the district in which it is distributed for a certain period of time, and that if the distribution is in any way cut short the deaths from cholera begin to decline within about three days of the date at which the distribution is stopped.16
14 Edinb. Med. Jour., i. 1122.
15 Trans. of the Epidemiological Soc., ii. 428.
16 Lancet, April, 1868, p. 217.
Analogous instances are furnished by every cholera epidemic of which the history has been accurately observed, including that which extended so widely over the United States in 1873. Most of the following are cited from the official reports prepared, under the direction of the Surgeon-General of the army, by Surgeon Ely McClellan and Dr. John C. Peters. Several of the first cases, however, are foreign.
In 1861, at a station in India, some fresh cholera dejecta found their way into a vessel of drinking-water. Early on the following morning a small quantity of this water was swallowed by nineteen persons, five of whom were attacked with cholera between the first and the third day afterward.17 In 1876 an outbreak of cholera took place in a village in Hindostan, which followed the arrival of wedding-guests, one of whom was attacked, and from whom it rapidly spread. The soiled clothes of one or more of the patients were washed in a pool from which all the villagers obtained their drinking-water, and on the discontinuance of this source of water-supply cholera speedily diminished in frequency and fatality.18 In the German epidemic of 1873 many cases occurred where persons deriving their drinking-water from special sources were attacked with cholera, while their neighbors, supplied from a different source, remained free. Again, it has frequently happened that outbreaks of cholera have been checked by the prohibition of the suspected water and the substitution of a pure supply.19 It seems probable that a very small portion of cholera discharges suffices to infect a very large body of water and maintain its infectiousness for a considerable time.