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 being _susceptible_. 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 a _single_ exception to the _law of uncertainty_ that
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 a _general_, what was at first too
hastily concluded to be an _absolute_ rule.
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 the _only 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 a _single case_, and two other gentlemen took occasion to
say, that they had each seen a case of _second Small Pox_—both of which
proved _fatal_.” And Dr. Thomson tells us (Historical Sketch, &c. p.
279), that “since the publication of my ‘Account of the Varioloid
Epidemic,’ I have seen above _two hundred_ additional examples of Small
Pox in Edinburgh, making in all _eight hundred and thirty-six_ cases of
this disease, which have come under my observation since June, 1818. Of
the whole number, _two hundred and eighty-one_ have occurred in
individuals who had neither had Small Pox nor Cow Pox, and of these
fully more than _one_ in _four_ died; _seventy-one_ had previously
passed through _Small Pox_, and of these _two_ have died; and _four
hundred and eighty-four_ had undergone the process of _Vaccination_,
and of this number _one_ only 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 that _two_ deaths 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
deaths _certain_, against _two 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 of _two persons_ out 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 only _eight_ cases 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 a _safe_ disease; 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.
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CONCLUSION.
The following are the important conclusions which may obviously be
deduced from the satisfactory evidence which has been detailed.