28 JULY 1866, Page 15

IS CHOLERA CONTAGIOUS?

[To THE EDITOR OF THE "SPECTATOR."] SI11,—.You will pardon me for writing to say that your remarks as to the non-infectiousness of cholera are not quite on a level with the knowledge we have now on the subject, and being not quite true, are likely to do mischief. Dr. Southwood Smith was a non-con- tagionist, and so were many men of like note who did not see the last epidemic of cholera, but I really do not know that you can put your fingers on any man of scientific mark nowadays who holds to the like belief. Sir Thomas Watson says, when arguing for the contagiousness of certain fevers, that the non-conta- gionists were ordinarily men "of Liberal opinions,"—rather a foolish remark, but, as poor Dr. Baly said to me, "about the only one in his book." But I am sure that most, if not all, men who have seen the later epidemics of cholera, whether they be Liberals or not, believe in its being infectious. The American doctors, I think, who have always been anti-con- tagionists in an extreme degree, have given in their adhesion at last, if I am not very greatly mistaken, to the contagion theory. So much for authority. Now for facts, so far as a man like myself, who is now rather concerned with physiology than with physic, may be allowed to give them. If you have a cholera patient casting forth the excretions of that disease into the air, and if those excretions are not deodorized and disinfected, you will have gene- rated by that individual an atmosphere into which persons entering will be likely to contract cholera. This is certain, and it gives the key to the fact which you mention, that removal from a locality sopped through and soaked with cholera evacuations, and consti- tuting thus a concentrated atmosphere of infective matters, to a locality as yet unimpregnated with cholera fomites, arrests the disease. By such "a march of a few miles" you leave all the mass of unclisinfected matters behind you ; and camping your men out in liberally interspaced tents, if any man is taken with cholera, the sphere which the exhalations from him will fill is less likely to have other men within its periphery than it would were he in a roofed barrack, with only 1,200 cubic feet of air per man.

But fact second. Cholera can, like many other things in nature, originate in more ways than one, in spite of Maupertuis' Law of Economy or Parsimony and of Sir W. Hamilton's endorsement of the same. And it does arise, as at St. Kilda, where no carriage by human intercourse can have been possible. This fact, for fact it is, and there are many like unto it, when coupled with the idolon Theatri Entia non sunt multiplicanda prmter necessitatem, has blinded many eyes to the infectious nature of many diseases besides cholera.—Your obedient servant, M. D.