CHAPTER III.

HISTORICAL SKETCH.

In the Old Testament, frequent allusion is made to contagion, particularly in Leviticus, where directions are given for the expurgation, from the system, of that principle; for the isolation of persons possessed of it; and the cleansing of garments therewith infected.

The earliest Grecian historians make reference to it, and Thucydides, in his History of the Plague, attributes some occurrences in its career, to the operation of that principle.

Dr Winterbottom[1] writes thus, of an ancient physician—“Aratæus says, that the miserable patients (those ill of Elephantiasis), were banished into deserts, or to the top of mountains, where the kindness of their friends occasionally attended their distresses; though perhaps they were more frequently deserted.”

Footnote 1:

Dr Winterbottom on Sierra Leone.

Cælius Aurelianus, a noted physician, says—“Some advise that a person labouring under this disease, should be turned out of town, if a stranger, or if an inhabitant, be banished to some distant part; others advise the patient to be totally abandoned.”

These expressions relate to contagion generally.

Atmospheric contagion is not specified, though perhaps even then, it may have been thought to exist.

As already said, later physicians thought that contagious diseases were propagated in three different ways, _1st_, by actual contact with the matter or virus itself; _2dly_, by fomites, or by contact with clothes tainted with it; and, _3dly_, by infection, or by air holding it in solution.

But it is to contagion, as diffused through the air, that the observations that are to follow are directed. So we shall, for the present at least, dismiss the other two modes of its action, that by contact, and that by fomites or tainted clothes, with the expression of our belief in their existence, as modes of the propagation of disease.

In 1777, Dr Haygarth, an English physician, began to investigate the laws that regulate the action of contagious poisons, and for the first time they obtained a scientific examination, and became the subject of experiment, if, perhaps, are excepted the labours of Lind, whose observations appeared about the same time.

Dr Haygarth believed in the propagation of disease through the direct application of contagious matter, such, for instance, as that of small-pox; but of this none have expressed any doubt worthy of notice; for the fact is well known, and often witnessed, by inoculation for small-pox and cow-pox.

At the time at which Dr Haygarth wrote, very vague and extravagant notions were held on the subject of contagious poisons diffused in the air—of air holding in solution contagious poison, or, as we have determined to call it—Atmospheric Contagion.

It was believed to extend itself to great distances, and there to develope its powers.

His opinions on the subject were, at the time of their publication, quite original; and as they are such as are usually held, to this day, by most intelligent practitioners, the most important will be transcribed here.

In a letter to Dr Percival, on the prevention of infectious diseases, published in 1801, Dr H. says—“I have long thought that there is no subject on which a physician could employ his time and ability more advantageously for the benefit of his fellow-creatures, than in the investigation of febrile contagion, in order to ascertain the laws by which it is communicated, and by what means it may be prevented. It is well known to be the cause of very extensive destruction in the army, the navy, and in large towns.”

“In 1777 I began to ascertain, by clinical observations, (_i. e._ observations made at the bedside of a patient,) according to what law the small-pox infection, and, in 1780 and 1781, according to what law the febrile infection, is propagated.”—“I found that the pernicious effects of small-pox miasms (that is, airs or vapours) were limited to a very narrow sphere. In the open air, and in moderate cases, I discovered that the infectious distance does not exceed half a yard.”—“Hence it is probable that, even when the distemper is malignant, the infectious influence extends to but a few yards from the poison.”—“I soon also discovered, that the contagion of fevers was confined to a much narrower sphere.”

“You will recollect, my dear friend, that at this time (1781) my attention was much engaged in the investigation of the nature of the small-pox poison. I was struck with the difference of the periods in those two maladies during which the infection remains in a latent state, that is, the interval of time which elapses between the patient’s exposure to the pestilential influence and the commencement of the fever. In the typhus, this period appeared to be much longer than in small-pox.”

The period between the exposure to what is considered infection, and the period of the manifestation of disease, certainly does vary in different distempers. In those in which palpable contagious poisons are produced, and where they are palpably applied to the system, the interval is known, and seldom varies; but in those where a palpable poison is not recognised, or where it is said to act exclusively through the air, it is found that the interval is sometimes short, sometimes long, and manifests none of that precision almost always observed in reference to the first class of diseases.

Dr Haygarth again says, “When the room of a patient ill of an infectious fever is spacious, airy, and clean, few or none of the most intimate attendants will catch the disease.”

“Among the middle and higher ranks of society in Chester and its neighbourhood, during a period of thirty-one years, I scarcely recollect a single instance of the typhus fever being communicated to a second person, not even during the epidemics of 1783 and 1786, which excited a general alarm in that city, Fresh air and cleanliness were the only means which I employed to prevent infection. Doors and windows were kept open as far as the season, and other circumstances, would permit. Curtains were drawn to exclude the light, but not the free circulation of air. All clothes, utensils, &c. used by the patient were immersed in a vessel of cold water immediately, and, when taken out of it, carefully washed. The floors were kept clean, and vinegar was sometimes, but not always, employed to sprinkle. It was thought to be more easy to remove than to correct the poison.”

Dr Haygarth deserves much credit for his judicious treatment, and by it he had the satisfaction of seeing much public good effected. His principles are yet acted upon with the very best effects; but it will be shewn, at a more advanced part of this work, that the check put to the progress of disease, was rather to be attributed to the removal of an atmosphere loaded with unwholesome emanations, than to any power those steps or measures had, of rendering innocuous, by dilution, a specific contagious poison.

Dr Haygarth continues—“The whole evidence which I have been able to collect, incontestibly leads to this very important conclusion, that febrile infection extends but to a very narrow sphere from the person.

“It appears highly improbable that the typhus infection should ever be communicated in the open air, by the common intercourse of society; because visitors, and even attendants, with very few exceptions, escape the fever, when exposed to it, in even the same chamber, if clean, airy, and spacious.

“The quantity of miasms (unwholesome or poisonous air) respired in the latter, is incomparably more than it can be in the former situation. It is not, however, intended to be asserted that such an event is impossible, if a person on purpose, or by some rare accident, were to breathe the air which immediately issues from a patient, or from clothes fully impregnated with the poison.

“During my long attention to this inquiry, not a single instance ever occurred to prove that persons liable to the small-pox could associate in the same chamber with a patient in the distemper, without receiving the infection.

“We have no certain knowledge in what manner infectious fevers are received into the body. According to the most plausible conjecture they appear to be communicated by poisonous vapours, which issue from the breath, or the insensible perspiration, or the excretions of a patient in the distemper. These miasms are probably taken into the body by the absorbents of the mouth, nostrils, lungs, stomach, or skin.”

Under the able investigation of Dr Haygarth, the doctrine of infection has been deprived of much of its extravagant character. Under his examination it is found losing that widely extended range of action, and that extreme virulence, that had hitherto marked its history.

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.

To Dr Joseph Adams we are indebted for an excellent treatise on animal poisons, one that is much valued for the information and clear views it contains. The following is an extract from the work in question.

“By contagion I would understand those diseases with the origin of which we are now unacquainted, but which at present can only be propagated by contact with a person, or matter from a person under similar disease. Contagious diseases, which it is now our business to consider, may be divided into chronic and acute, of the former are the itch, and several others. These are for the most part incurable by the unassisted powers of the constitution. The acute of which are the small-pox, and many other exanthemata, (these are those diseases accompanied with fever) marked with a peculiar eruption, and that attack only once, such as measles, and scarlet fever produce a critical fever, which ceases with the disease.

“The chronic may attack a person as often as he is exposed to the exciting cause, the acute, for the most part, leave the constitution no longer susceptible of their operation.”

After pointing out the modes of communication of contagious diseases by contact and by fomites, he says, “Infectious diseases, on the contrary, may be traced in their origin, and do not require for their production matter similar to their effects, but may at any time be generated by crowding together the sick or wounded of any description. Of this kind are the hospital, prison, or ship-fever, camp dysentery, and some peculiarly malignant ulcers. Though these diseases, when formed, may produce their like in others, yet we can always trace their origin to causes different from their effects.”

From the London Cyclopædia the following extract is taken.

“There does not appear to be any distinction commonly made between contagious and infectious diseases.”

This extract proves how much confusion there exists, with the terms infectious and contagious. Here they are said to be used synonimously, and in that of Dr Bateman just quoted, a great distinction is drawn.

Such are a few of the facts connected with the history of contagion, which are most worthy of notice, in a work of this kind.

This sketch will afford some idea of the most rational views which have been, and still are, held on the subject; and of the light in which it is at present regarded by the medical world.

It is feared that the extracts which have been given, may appear too copious, but it has been thought highly proper, that the opinions of those justly considered, the greatest authorities on the subject, should be given: and that they might not be misunderstood, they have been, for the most part, presented verbatim.