CHAP. III.
Such having been proved to have been the destructive consequences of Small Pox, previous to the introduction of Vaccination, we are fully prepared to enter upon the second query proposed,—What influence has Vaccination exerted over these consequences—1. by extensively superseding the cause—and 2. by essentially interfering with the effect?
The name of Dr. Jenner is too intimately associated with the subject of Vaccination to admit of the latter being referred to without some allusion being made to the former; and I should ill testify my sense of the truly valuable blessing which Jenner has been the means of conferring upon mankind, were I altogether to omit any expression of my admiration of the superior perception which enabled him to infer the probable consequences of facts, which must have been long familiar to hundreds without having given rise to any important suggestion, and of the zeal and ability with which he prosecuted his enquiries on the subject, or my high esteem for the generous disinterestedness with which he made known to the world his most useful discovery. “It will,” (to use the words of Sir Gilbert Blane,) “in the eyes of future ages, be deemed an epocha in the destinies of the world, and one of the highest boasts of the country in which it took its rise, with a sense of unrequitable obligation to the individual who first disclosed and promulgated the secret, by drawing it from the dark recesses of rural tradition, and rendering it available to the whole human race.”
It is not, however, my intention to enter into any detail of the mode in which Vaccination originated, or of the circumstances which accompanied its introduction into practice. It will suffice to state, that its supposed efficacy in preventing the occurrence of Small Pox, was founded upon repeated observation, that the milkers employed in the great dairies of Gloucestershire and the neighbouring counties, who became affected with a disease which prevailed among the cows, and to which the name of Cow Pox had been given in consequence, were very generally rendered insusceptible of the Small Pox infection, even when attempted to be communicated by means of inoculation. Dr. Jenner put this fact to the test of repeated experiment, and finding it thus confirmed, proposed introducing the Cow Pox into the human constitution artificially, as a means of securing it against the dangers of Small Pox, and, in the end, of entirely exterminating the latter disease; for it must appear very evident, that if every individual could in any way be rendered incapable of being infected by Small Pox, the infection itself must necessarily become entirely extinct.
In prosecuting my enquiries into this part of my subject I shall, as far as may be, confine myself to an examination of facts calculated, as I conceive, to remove every reasonable doubt respecting the true value of Vaccination.
The first essential fact, to which I would direct the attention of my readers, is the very striking diminution in the number of deaths from Small Pox, which has taken place within the bills of mortality of London, since the introduction of Vaccination. This diminution is equally remarkable, whether we refer to the actual number of deaths from this cause, or to the relative proportion which they bear to the whole amount of deaths occurring in any given year or number of years. Thus taking the averages calculated on periods of five years each, as is shewn in the table (No. 2), it will appear evident not only that the amount of diminution has been most gratifying and satisfactory, but that, in proportion to the increasing employment of Vaccination, it has been regularly progressive; so that the number of deaths from Small Pox, instead of amounting to one in ten of the whole, as was the case for the ten years which preceded the introduction of Vaccination, has during the last ten years, actually amounted to less than one in twenty-eight, or little more than one-third of the former proportion.
If we compare the number of deaths from Small Pox, which took place during the twenty-five years (from 1784 to 1798 inclusive) which immediately preceded Vaccination, amounting to 46,996, with the number which has taken place during the twenty-five years which have elapsed since its introduction (from 1799 to 1823 inclusive), amounting to 25,869, we shall find that an actual diminution has taken place of no fewer than 21,127, or nearly one half of the whole. It may, therefore, be confidently assumed, even upon this very simple calculation, that a number of lives equal to this diminution has been saved by Vaccination, within the bills of mortality alone. And as this diminution in the amount of mortality from Small Pox is going on in a progressive ratio, it is probable that the next twenty-five years will afford a yet more striking result.
If we extend this calculation to the whole of Great Britain and Ireland, assuming that the ratio in the diminution of deaths has been the same over the united kingdom as within the London bills of mortality—(and there are various good reasons for believing that it has been greater)—we cannot but be struck with the immense saving of human life which has already taken place. Sir Gilbert Blane and Dr. Letsom separately calculated the annual loss of lives from Small Pox, in Great Britain and Ireland, during the last thirty years of the eighteenth century.—One of these eminent physicians estimated them at 34,260, and the other at 36,000 (Moore’s History of Small Pox, p. 300): For our present purpose, we will take a medium number, as being probably nearest to the truth. Assuming then, that the number of deaths from Small Pox, in the United Kingdom, during each of the twenty-five years which preceded the introduction of Vaccination, amounted to 35,000, the amount, during the whole of that period, must have been 875,000. But if the diminution on the whole of this number has been equal to that which is proved to have taken place within the London bills of mortality, during the last twenty-five years, it must have been reduced to 481,644 only, and an actual saving of the lives of 393,356 individuals must have been accomplished.
These calculations agree pretty nearly with estimates published in the year 1820, by Sir Gilbert Blane, founded on similar documents. His calculations extend to the parishes not included within the bills of mortality, and he comes to the following conclusion on the subject:—“It appears, therefore, that even under the very imperfect practice of Vaccination, which has taken place in the metropolis, 23,134 lives have been saved in the last fifteen years, according to the best computation that the data afford”—(Sir G. Blane on Vaccination, p. 7). But however remarkable and satisfactory this immense saving of human life, in the country where Vaccination originated, may appear, as an unanswerable evidence of its efficacy, the result has been still more decisive in many foreign countries, where it has been much more generally employed. In proof of this, I shall again quote the very valuable little work of Sir Gilbert Blane, (which, by the way, I should strongly recommend to the attention of the public, as containing much valuable matter and sound argument within a very small compass). He states, (p. 7-8) “In the summer of 1811, the author was called to visit, professionally, Don Francisco de Salazar, who had arrived a few days before in London, on his route from Lima to Cadiz, as a Deputy to the Spanish Cortes. He informed him, that Vaccination had been practised with so much energy and success in Lima, that for the last twelve months there had occurred not only no death from, but no case of, Small Pox: that the new born children, of all ranks, are carried as regularly to the Vaccinating house as to the font of baptism; that the Small Pox is entirely extinguished all over Peru; nearly so in Chili; and that there has been no compulsory interference on the part of the government to promote Vaccination.”
Sir Gilbert goes on to say, that “it is now matter of irrefragable historical evidence, that Vaccination possesses powers adequate to the great end proposed by its meritorious discoverer, in his first promulgation of it in 1798, namely, the total extirpation of Small Pox. The first proof of this was at Vienna, where, in 1804, no cases occurred, except two strangers, who came into the city with the disease upon them. In 1805 there did not occur a single death from it in Copenhagen. Dr. Sacco, the indefatigable superintendent of Vaccination in Lombardy, stated in his annual report, 3d January, 1808, that the Small Pox had entirely disappeared in all the large towns in that country; and that in the great city of Milan it had not appeared for several years. Dr. Odier of Geneva, so favourably known for his high professional, scientific, and literary acquirements, testifies that, after a vigorous perseverance in Vaccination for six years, the Small Pox had disappeared in that city and the whole surrounding district; and that, when casually introduced by strangers, it did not spread, the inhabitants not beingsusceptible. The central committee in Paris testify, in their report of 1809, that the Small Pox had been extinguished at Lyons and other districts of France.”
“These are selected as some of the earliest and most remarkable proofs of the extirpating power. But it is demonstrable, that if at the first moment of this singular discovery, at any moment since, at the present or any future moment, mankind were sufficiently wise and decided to vaccinate the whole of the human species, who have not yet gone through the Small Pox, from that moment would this most loathsome and afflicting of all the scourges of humanity, be instantaneously and for ever banished from the earth.” (p. 8).
These, and such as these, then are the great, the undeniable facts, which must, I think, carry irresistible conviction to every reflecting and unprejudiced mind respecting the true value of Vaccination. And it is these facts which furnish us with an answer to the second question proposed—What influence has Vaccination exerted over the destructive consequences of Small Pox? which it must be truly gratifying to every philanthropic mind to contemplate. In the course of twenty-five years, in our own country, where it has been very partially employed, it has actually been the means of saving a number of lives, amounting to 393,356; and if it be true, as supposed by Sir Gilbert Blane, that Small Pox induced “blindness, deformity, scrofula, or broken constitutions,” in as many who recovered from the disease as died in consequence of it, then have an equal number been saved from these dreadful calamities. But abroad, where it has been more generally employed, Vaccination has, in many places, actually exterminated the Small Pox altogether.
From what has already been said, it will be evident, that Vaccination has produced these very beneficial consequences in two ways. 1. By superseding an efficient cause of the spread of infection, namely, the practice of inoculation for Small Pox. And 2. by essentially interfering with the effect of the infectious virus.
The increased number of deaths, which took place during the period when inoculation for Small Pox was generally employed, is sufficient to prove the influence of Vaccination to have been considerable in the former way; but a formal application having been made to me to inoculate a child for Small Pox, since I commenced these remarks, I think it right to call the attention of the public more decidedly to the pernicious tendencies of the practice.
The attention of the medical profession, and of the public generally, was soon excited by the increasing number of deaths after the introduction of inoculation, and exertions were made to check it, particularly by the establishment of the Small Pox Hospital. This, no doubt, had some effect, by separating a part at least of those to whom Small Pox was artificially communicated from the rest of the community; but the event proved that this was by no means an adequate defence against the factitious causes of infection, which were daily called into action. The Small Pox Hospital still exists, and it is a very remarkable fact, that, for several years after the discovery of Vaccination, out-patients continued to be inoculated at that institution. This, no doubt, contributed to prevent the proportion of deaths from Small Pox in London from diminishing so rapidly as would otherwise have been the case, and as has been the case, since this “unaccountable infatuation,” as Sir Gilbert Blane very justly calls it, has been discontinued. But, as the same eminent physician properly remarks (p. 6), “it was in the rural population that the effect of inoculation in diffusing Small Pox was chiefly felt. In this situation, there is much less intercourse of persons with each other than in towns, so that not only many individuals escaped, from their not being exposed to infection during their whole lives, but whole districts were known to have been exempt from it for a long series of years before it was universally diffused by inoculation.” We may, therefore conclude, that while the number of deaths from Small Pox, within the bills of mortality, was increased in the proportion exhibited in the tables by means of inoculation, in the country the increased mortality from this cause was in a much greater ratio. This supposition is in a great degree confirmed by the effects occasioned by a renewal of the practice of inoculation, in Norfolk, in the year 1819, as recorded by Mr. Cross, in his History of the Epidemic Small Pox, which at that time prevailed in the city of Norwich and the county of Norfolk. Mr. Cross mentions many instances of the disease being introduced into parishes, in which it did not before exist, by means of inoculation, the contagion afterwards spreading in all directions; and affirms (p. 272), that “thirty-eight surgeons, who from various motives, practised it, lost among those to whom they had thus given the disease, twenty-one patients; fourteen surgeons reported, that fifty-five deaths had been occasioned in the same way within their knowledge; and five other surgeons observed, that they had known several who fell a sacrifice to the practice.” It admits then of the most incontestable proof, and it is a fact, which cannot be too deeply impressed upon the minds of the public, that inoculation for Small Pox is a practice attended with very considerable danger to the individual who passes through it, while to society in general, it has been productive of the most pernicious consequences. Is it too much then to affirm, that it cannot be employed without great moral guilt being incurred both by those who may require its performance, and by the medical practitioner who shall be induced to practise it?
But by far the most important mode in which Vaccination has been productive of the equally astonishing and gratifying consequences, which have been proved to have resulted from it, has been by its essential interference with the effect of the infectious matter of Small Pox, either by entirely preventing the occurrence of that disease, or by stripping it of all its dangerous and formidable characteristics—rendering it, in the comparatively few instances in which it has taken place at all after Vaccination, mild in its attack, and perfectly harmless in its consequences.
It very generally happens, when a discovery is made which promises to exert any considerable influence over the happiness of man, that its capabilities cannot for some time be very accurately defined; and that the effects, which a few years’ experience shall prove it to possess the power of producing, will, at the commencement, be either undervalued or overrated. It would not, perhaps, be difficult to adduce instances of both. And it can scarcely excite surprise, that something like this should have been the case with incomparably the most important discovery of modern times, for such we may truly esteem Vaccination, whether we consider it as a means of preserving life, or of obviating effects, perhaps, even more deplorable than the loss of life itself.
If then, the first promoters of Vaccination were led, from their ardour in a cause of such vital interest to the whole human race, and before time had been allowed to afford sufficient data whereon to found a more correct opinion, to conclude that Vaccination would, in every instance, prove an absolute and infallible preventive of future susceptibility of Small Pox infection, let us not, on that account, run into an error incalculably more dangerous in its tendency, and underrate or deny altogether the degree of security which it actually affords. That this is more than sufficient to render it worthy of universal adoption, there cannot be any reasonable doubt; but it would have been strange indeed, if, in the undeviating uniformity of its effects, Vaccination had formed asingleexception to thelaw of uncertaintythat attaches to every other agent, which it has, at any time, been permitted to mankind to employ for the promotion or preservation of the health of the human constitution: and, considering the innumerable varieties which prevail in the latter, we ought rather, perhaps, to feel surprise that the influence of Vaccination over all these varieties, should have been proved to be so similar as to have justified us in considering as ageneral, what was at first too hastily concluded to be anabsoluterule.
That the great majority of instances in which Vaccination has afforded perfect security against any future attack of Small Pox, fully warrants this conclusion, the results already detailed are sufficient to prove. What proportion these cases bear to the comparatively few, wherein the protection has been less perfect, it will not be possible to discover, because we are unable to ascertain how many hundreds of thousands or millions have passed through the vaccinating process. But little difficulty would be encountered, however, in ascertaining the full amount of the few who have had any thing bearing the slightest resemblance to an attack of Small Pox after Vaccination: these, for the most part, have been carefully recorded, and a degree of importance has certainly been attached to them greater than is warranted, either by their number, their severity, or their results.
It is of still more importance, however, to know, that when Small Pox has occurred after Vaccination, it has been so essentially altered in the severity of its symptoms, and in the degree of danger arising from it, as to have rendered it entirely harmless in almost every instance; and although fatal cases have taken place in a few insulated and peculiar examples, they have been very much more rare than those which have occurred in consequence of inoculated, or even of secondary Small Pox. Sir Gilbert Blane, after describing (p. 10-11) the mild character of the disease as occurring after Vaccination, continues thus—“What forms the strong line of distinction from proper Small Pox is, that, with a few exceptions, it does not advance to maturation and secondary fever, which is theonly period of danger. I am not prepared to deny that death may have occurred in a few instances; nay, there seems sufficient evidence that it actually has; but then adverse cases are so rare as not to form the shadow of an objection to the expediency of the general practice. A few weeks ago, at a meeting of this (the Medical and Chirurgical) Society, at which forty members and visitors were present, I put the question, whether any of these eminent and extensive practitioners had met with any fatal cases of this kind. Two gentlemen had each seen asingle case, and two other gentlemen took occasion to say, that they had each seen a case ofsecond Small Pox—both of which provedfatal.” And Dr. Thomson tells us (Historical Sketch, &c. p. 279), that “since the publication of my ‘Account of the Varioloid Epidemic,’ I have seen abovetwo hundredadditional examples of Small Pox in Edinburgh, making in alleight hundred and thirty-sixcases of this disease, which have come under my observation since June, 1818. Of the whole number,two hundred and eighty-onehave occurred in individuals who had neither had Small Pox nor Cow Pox, and of these fully more thanoneinfourdied;seventy-onehad previously passed throughSmall Pox, and of thesetwohave died; andfour hundred and eighty-fourhad undergone the process ofVaccination, and of this numberoneonly died; results (adds Dr. Thomson) which evince, beyond the power of cavil, the beneficial effects of Vaccination in protecting the human constitution from the dangers of Small Pox, and the great advantages which must ultimately arise from the universal adoption of this practice.”—Perhaps the most fatal epidemic Small Pox, which has occurred of late years, was that which took place at Norwich in 1819. A history of it was published in the following year by Mr. Cross, and the general result was in perfect accordance with Dr. Thomson’s experience of the epidemic at Edinburgh.
Mr. Cross relates thattwodeaths only took place after Vaccination, and justly observes, that “these can have no weight against the practice of Vaccination compared with 10,000 vaccinated individuals, living in the midst of a contaminated atmosphere; with 530 deaths among little more than 3000 who had neglected to be vaccinated; and with the occasional occurrence of regular Small Pox in those who formerly had the disease.” Of the 10,000 persons thus protected by Vaccination, the Reviewer of Mr. Cross’s History, &c. observes (Edin. Med. and Sur. Journal, Vol. xvii. p. 127), “Had these persons been protected by variolous (Small Pox) inoculation, conducted in the best manner, and in the most favourable circumstances, at least 33 of them (1 in 300) would have died of the process intended to protect them; so that in comparing the advantages of the two methods of protection, we have to weigh 33 deathscertain, againsttwo contingent on the invasion of an epidemic Small Pox, and then we have to consider, whether there might not be nearly as great a chance oftwo personsout of 10,000 inoculated for Small Pox, taking a fatal Small Pox on exposure, at a subsequent period of life, to a virulent contagion.” I shall conclude the evidence I think it necessary to bring forward on this part of my subject with the following extract from the Report of the National Vaccine Establishment for 1820. In reference to the occasional cases wherein the protection from Vaccination is not quite complete, the Board observes,—“Yet the value of this important resource is not disparaged in our judgment; for after all, these cases bear a very small proportion to the number of those who are effectually protected by it. The reports of the Vaccinators at the several stations in the metropolis, give onlyeightcases of Small Pox out of nearly 67,000 vaccinated by them, since the first establishment of this board; and as the Small Pox has prevailed extensively in London, these persons so vaccinated, must have been frequently exposed to contagion, and consequently the protecting effect of Vaccination must have been submitted to as severe a test as can well be imagined. Moreover, we have the most undoubted proofs from experience, that where Vaccination has been performed perfectly, Small Pox, occurring after it, is almost universally asafedisease; and though ushered in by severe symptoms, has hardly ever failed to be cut short before it had reached that period at which it becomes dangerous to life.”
I shall not weaken the force of this evidence by entering into any minor question connected with this great subject—such as the probability of many of those, in whom Small Pox has succeeded to Vaccination, having passed through the latter process imperfectly, either in consequence of the matter employed not having been genuine; of the constitution not having shown adequate signs of being properly influenced by the process; or of the latter having been interfered with in its progress, by the accidental injury of the pustules, &c. No doubt all these causes may have had some effect, in consequence of the carelessness of parents, or of the practice of non-professional inoculators: in a matter of so much importance then, it behoves parents to guard against these causes of failure, which it is now certainly within the power of the poorest to do. Nor shall I detail the arguments by which Professor Thomson has rendered it probable that the pustular eruption, which has been so long known in this country under the name of Chicken Pox, is very nearly related to Small Pox itself, and is in reality the effect of the same infectious virus modified by various incidental circumstances; such as season of the year, the previous existence of Small Pox or of Cow Pox in those affected by it, or some peculiarity in their constitution not sufficiently obvious to be recognised by our senses. When I rest my proof of the power of Vaccination over the destructive consequences of Small Pox on the results which have been detailed, I am satisfied that it is fixed upon a basis too firm to be shaken by argument, and which will long outlive the feeble attacks of ignorance or prejudice.