108 



CHOLERA, ASIATIC. 



single cholera patient may cause the development of 

 an epidemic. 



10. That certain facts tend to prove that a single 

 individual (with much greater reason many individ- 

 uals) coming from a contaminated place, and suffer- 

 ing from diarrhoea, is able to cause the development 

 of a cholera epidemic ; or, in other words, that the 

 diarrhoea called premonitory is able to transmit 

 cholera. 



11. That in almost all cases the period of incubation, 

 that is to say, the interval between the moment when 

 the individual may have contracted the cholera poison 

 and the commencement of the premonitory diarrhoea, 

 or of confirmed cholera, does not go beyond a few 

 days ; all the facts cited of a longer incubation belong 

 to the class where the contamination may have taken 

 place after departure from the infected place. 



12. That there is no known fact which proves that 

 cholera has been imported by living animals ; but it 

 is reasonable, nevertheless, to consider them, in cer- 

 tain cases, as belonging to the class of objects called 

 susceptible. 



13. That cholera can be transmitted by articles in 

 common use coming from an infected place, and espe- 

 cially by those which have been used by cholera pa- 

 tients ; and it also results from certain facts that the 

 disease may be transported to a distance by these 

 same articles when closely shut up from the outer 

 air. 



14. That although it is not proved by conclusive 

 facts that the bodies of patients dying with cholera 

 can transmit the disease, it is prudent to consider 

 them as dangerous. 



15. That maritime communications are by their 

 nature the most dangerous ; that it is they which 

 propagate most surely cholera at a distance, and that 

 next to them comes communication by railroad, 

 which in a very short time may carry the disease to 

 a great distance. 



16. That great deserts are a most effectual barrier 

 to the propagation of cholera, and the Conference 

 believes that it is without example for this disease 

 to be imported into Egypt or Syria, across the desert, 

 by caravans from Mecca. 



fl. That all crowding together of human beings, 

 among whom cholera has been introduced, is a favor- 

 able condition for the rapid spread of the disease 

 and, if this crowding exists under bad hygienic 

 conditions, for the violence of the epidemic among 

 them. 



That in this case the rapidity of the extension of 

 the disease is in proportion to the degree of crowd- 

 ing, while the violence of the epidemic is, other 

 things being equal, so much the greater according 

 as individuals have been little exposed to the chole- 

 raic influence or not at all ; that is to say, in other 

 words, individuals who have already been exposed to 

 the influence of a cholera atmosphere enjoy a sort 

 of relative and temporary immunity which countrfr- 

 balances the bad effects of crowding. 



Finally, in the case of a dense crowd, the more 

 rapid its separation, so much the more rapid is the 

 cessation of the epidemic, at least if new arrivals of 

 unaffected persons do not furnish new aliment for the 

 disease. 



18. That the intensity of cholera on board ships 

 crowded with men, is, in general, proportionate to- 

 the crowding, and is so much the more violent, 

 other things being equal, if the passengers have not 

 resided in the focus of cholera from which they 

 started ; that on crowded ships the spread of cholera 

 epidemics is ordinarily rapid ; finally, the Commis- 

 sion adds that the danger of importation by ships, 

 and that of giving rise to a grave epidemic, are not 

 entirely subordinate to the intensity, nor even to the 

 existence of choleraic symptoms appearing during 

 the voyage. 



19. That the crowding together of people coming 

 from a place where cholera reigns in a lazaretto, has 

 cot the effect of producing, 'among the people at 



quarantine, a great extension of the disease ; but 

 that such a gathering is nevertheless very dangeroua 

 for the neighborhood, as it is calculated to favor the 

 propagation of cholera. 



20. That great gatherings of men (armies, fairs, 

 pilgrimages), are one of the most certain means for 

 the propagation of cholera ; that they constitute the 

 great epidemic foci which, whether they march after 

 the manner of an army, or whether they are scat- 

 tered, as at fairs and in pilgrimages, import the dis- 

 ease into the country which they traverse ; that these 

 gatherings, after having been exposed, usually in a 

 rapid manner, to the influence of cholera, become 

 much less susceptible to its power, and that it disap- 

 pears very speedily, unless newly-arrived persons 

 take the disease. 



21. That the hygienic and 'other conditions which 

 in general predispose a population to contract chol- 

 era, and consequently favor the intensity of the epi- 

 demics, are : misery, with all its consequences ; over- 

 crowding, particularly of persons in feeble health ; 

 the hot season ; want of fresh air ; the exhalations 

 from a porous soil impregnated with organic mat- 

 ters above all, with the dejections from cholera 

 patients. 



It appears demonstrated by experience that the 

 discharges of cholera patients contain the generative 

 principle of cholera; it is right to admit that drains, 

 privies, and the contaminated waters of towns may 

 become the agents for the propagation of this disease. 



It seems to result from certain facts that the soil 

 of a locality, once impregnated with cholera detritus, 

 is able to retain for a considerable length of time the 

 property of disengaging the principle of the disease, 

 and of thus keeping up an epidemic, or even of re- 

 generating it after it has become extinct. 



22. That the immunity which certain localities en- 

 joy, that is to say, the resistance, permanent or tem- 

 porary, general or > artial, opposed by these locali- 

 ties to the development of cholera within their limits, 

 is a fact which does not exclude transmissibility, but 

 which indicates that certain local conditions, not yet 

 entirely determined, are an obstacle to the develop- 

 ment of the disease. 



The same immunity, more or less complete, and 

 more or less durable, which the majority of persons 

 in the midst of an infected district enjoy, an immu- 

 nity which attests the individual resistance to the 

 toxic principle, is a circumstance to which we should 

 attach the highest importance. 



In point of view of epidemic development, it is the 

 corrective of transmissibility, and, viewed with re- 

 gard to prophylaxia, it sets in operation proper 

 means to arrest the ravages of the disease. 



23. That the air is the principal vehicle of the 



cholera principle The action of the 



cholera miasm is so much the more sure as it operates 

 in a confined atmosphere, and near the focus of emis- 

 sion It seems that it is with cholera 



miasm as it is with the miasm of typhus, which rap- 

 idly loses its power in the open air at a short dis- 

 tance from its starting point. , 



24. That the surrounding atmosphere is the prin- 

 cipal vehicle of the generative agent of cholera ; but 

 the transmission of the disease by the atmosphere, in 

 an immense majority of cases, is limited to a space 

 very near the focus of emission. 



25. That water and certain ingesta may also serve 

 as vehicles for the introduction into the organism of 

 the generative principle of cholera. 



This granted, it follows, so to speak, necessarily, 

 that the passages by which the toxic agent penetrates 

 into the economy are. principally the respiratory pas- 

 sages, and very probably also the digestive canals. 

 As for its penetration by the skin, nothing tends to 

 prove it. 



26. That the matter of the cholera dejections being 

 incontestably the principal receptacle of the morbific 

 agent, it follows that every thing which is contami- 

 nated by the discharges bee >mes also a receptacle 



