Dr Bateman, in his excellent work on contagious fever, after alluding to a prevalent opinion, that contagious poison is capable of diffusion in the air, says, “To one acquainted with the evidence which has been adduced relative to the properties of contagion, these opinions, and the terrors connected with them, appear equally unfounded and absurd, as are all creations of an over-excited imagination magnified by prejudice and alarm—for it has been proved, beyond the possibility of a doubt, by the concurrent testimony of a multitude of the ablest practitioners, who have had every opportunity of investigating the fact, and by all the experience which the establishment of fever boards and houses of recovery has afforded the means of accumulating, that no contagion whatever is communicable, even to the distance of a few feet, through the medium of the free and open atmosphere, and consequently that residence in a district where fever prevails is free from all danger. Nay, it has been further proved on the same undeniable evidence, that the house and even the apartment, occupied by the sick, may be rendered perfectly innocuous, the contagion being disarmed of its activity and virulence by dilution with pure air,” &c.
Dr Bateman gives the following facts—
“All the patients admitted into the London House of Recovery are transported in a litter by two others employed by the institution, enveloped in their uncleanly and tainted apparel. Yet the porters who have been daily occupied for the last eighteen months in conveying this double source of contagion, often the distance of two or three miles, and assisting them in and out of the litter, have never received the infection.
“Neither have the washerwomen, employed during the period of my attendance, (sixteen years) on the House of Recovery, occupied almost constantly in washing the apparel brought in by the patient, as well as the bed-linen, often much soiled by their excretions, and the cloths used by the patients in the house, ever been affected with the fever.”
Dr Patrick Russell, whose work on the plague is so well known, is the next writer to whose observations reference will be made. His personal observation of much contagious disease, and his high character, entitle his observations to much weight. They will amply shew, how the question before us has gained with the advancement of medical science. Some are subjoined.
“In the first place, the various and vague application of the term contagion has been the source of confusion. In foreign languages, as well as in English, it has sometimes been used for the plague itself, sometimes as synonimous with infections; sometimes for the virulent effluvia issuing from the sick, or from substances infected, and sometimes as a property common to various diseases.”
He is of the decided opinion, that plague is communicated, by contact of the body, with the poison, which is properly understood by the word contagion. He says—“The second mode of contagion is by the medium of the air. The effluvia arising from the diseased, received into the ambient air, form a pestiferous atmosphere, more or less impregnated with these effluvia, as it recedes from their source. That contagion is thus communicated in the chamber of the sick, appears from persons being infected without touching the diseased body, or any thing in the room that may be supposed to harbour infection.
“To what distance the tainted atmosphere extends is not yet known, but recent facts render it probable that the effluvia, when once transmitted into the air, are soon dispersed, blended with the common mass, or otherwise suffer such alteration as render them innocuous at no great distance from their source. It is probable, also, that those effluvia arise, in an active state, to no great height in the atmosphere.”
He adds, that the contagion by fomites, that is, impregnated clothes, is the most extensive in its operation; and that it spreads disease, not only in all quarters of a town, but also to remote regions. He asserts that the plague is conveyed into different streets, remote from one another, by the Jewish salesmen, and that he has known Armenian washerwomen infected by tainted linen. The infectious air of plague, according to him, when it adheres to substances not exposed to free ventilation, and closely packed, retains its vigour for along time, and in that state is transported to other countries: and he held it as proven that it retains its activity in a three months’ voyage from the coast of Syria to Marseilles.
He is disposed to think that the contagion of plague, rarely remains in the system longer than ten days, and that more danger is to be apprehended from the baggage of passengers who enter into lazarettoes, than from their persons.