Notwithstanding [he wrote] the happy effects of Inoculation, with all the improvements the practice has received since its first introduction into this country, it not very unfrequently produces deformity of the skin, and sometimes, under the best management, proves fatal. (P. 57.)
On the contrary, he said—
I have never known fatal effects arise from the Cowpox, even when impressed in the most unfavourable manner, producing extensive inflammations and suppurations on the hands; and as it clearly appears that this disease leaves the constitution in a state of perfect security from the infection of the Smallpox, may we not infer that a mode of Inoculation may be introduced preferable to that at present adopted, especially among those families, which, from previous circumstances, we may judge to be predisposed to have the disease unfavourably?
Inoculation was freely charged with exciting scrofula; thus Jenner observed—
In constitutions predisposed to scrofula, how frequently we see the inoculated Smallpox rouse into activity that distressful malady; and the issue does not seem to depend on the manner of the inoculation, for it as often occurs in those who receive it mildly as in those who receive it severely. (P. 60.)
Happily he had the grace to refrain from the explicit assertion that Cowpox was exempt from similar hazard; yet with characteristic inconsistency, was disposed to advance a claim for it as an expulsive irritant—
As we have seen [though he never showed] that the constitution may at any time be made to feel the febrile attack of Cowpox, might it not, in many chronic diseases, be introduced into the system, with the probability of affording relief, upon well-known physiological principles? (P. 60.)
A reader of the Inquiry in 1798 could never have supposed that it was an attempt to displace the existing practice of Inoculation. Nor is there any sign that Jenner at the time contemplated such an issue. He referred to Variolous Inoculation with respect, and was satisfied to suggest that in certain cases inoculation with Horsegrease Cowpox might be substituted with advantage. As to the permanent existence of Horsegrease Cowpox he was doubtful. Since, he said, the farmers had traced the infection to the Horse, “the appearance of the Cowpox may either be entirely extinguished or become extremely rare.” It may be replied that this behaviour on the part of Jenner was due to reserve and tact, but the reserve and tact are invisible. The Inquiry was simply what it appears—a hasty performance, which, in other hands, developed to more, far more, than its author contemplated. Subsequently he, and his friends for him, laid claim to years of research under the influence of supernatural foresight; but, with the Inquiry before us, I ask where is the evidence? I take the date, 14th May, 1796, when Jenner inoculated Phipps from the hand of Sarah Nelmes, as the time when the project of inoculation with Horsegrease Cowpox began to assume form, and I maintain that the character, order and dates of the Cases set forth in the Inquiry plainly show that they were got together to sustain the conclusion then arrived at. When Mr. John Simon descants on Jenner’s thirty years of incessant thought, watching and experimenting which resulted in the production of that Masterpiece of Medical Induction—The Inquiry, the answer is, Peruse the Inquiry, and then say where the fruit of thirty years of labour is to be found. The assertion is too absurd for discussion, whatever it may be as an article of faith.
The single point of originality in the Inquiry was the definition of the disease for which prophylactic efficacy was asserted. The dairymaids said Cowpox: the farriers said Horsegrease. Jenner said neither Cowpox nor Horsegrease, but their combination in Horsegrease Cowpox, which variety of Pox alone ensured life-long security from Smallpox. We shall see as we proceed how this position was surrendered and resumed, modified and confused beyond recognition. Let it suffice at present to say that the note of Jenner’s Inquiry was Horsegrease Cowpox and nothing else. Strike out Horsegrease Cowpox, and the affair is reduced to nonentity.
What was called the Variolous Test worked wonderfully for Jenner; and as we shall have to refer to it repeatedly, it may be well to describe and dispose of it at once.
We have seen how the Test was practised in the Cases in the Inquiry. Those who had undergone Cowpox were inoculated with Smallpox, and as the Smallpox did not “take,” they were assumed to be proof against that disease. Hence the absolute conclusion proclaimed Urbi et Orbi, that none inoculated with Cowpox could ever afterwards contract Smallpox.
It was replied, that some who had suffered from Cowpox had contracted Smallpox, and that others had received the disease by inoculation; to which Jenner’s summary answer was, “There must have been some mistake about the Cowpox; for no one can have genuine Cowpox and subsequently incur Smallpox, either by infection or inoculation.”
Cowpox was inoculated and propagated from arm to arm; and, in proof that the constitution was fortified against Smallpox, it was common to inoculate with Smallpox, which usually did not “take”; whereon the operator exclaimed, “Behold! the patient is insusceptible of Smallpox for ever!”
Such was the Variolous Test. It was to multitudes absolutely conclusive; and to question its validity was to exhibit a contentious and unphilosophic disposition.
What shall we now say concerning it?
First, that failures were numerous in Variolous Inoculation apart from Vaccination, and that it was not supposed that when a patient did not “take,” he was therefore insusceptible of Smallpox; nor even when he did “take,” that he was thereby rendered proof against Smallpox. So many of the successfully inoculated did subsequently fall victims to Smallpox, that Variolators at the end of last century were compelled to argue (like Vaccinators at the end of this) that Variolation was a guard, but not an absolute guard; and that when it did not altogether avert Smallpox, it modified and mitigated an attack. The excuse for failure was as artful as the motive was urgent: Variolation was too good a trade to be imperilled for lack of a little ingenuity.
Nevertheless, if we make full allowance on the score of frequent incapacity to receive Variolation, we have yet to explain, on a candid view of the whole evidence, how it was that in numerous cases Inoculation with Smallpox was ineffective after Inoculation with Cowpox.
“What can you urge against the Variolous Test?” was a frequent and imperious demand.
The explanation in general lay in the fact, that Variolation was attempted before the complete subsidence of the vaccine fever. The inoculation with Cowpox had set up a serious constitutional disturbance, and during that disturbance the Smallpox virus could not develop its malign energy. Let me show what I mean from the testimony of Jenner himself.
On 15th March, 1800, the Duke of York requested Jenner to proceed to Colchester to the 85th Regiment. Jenner was unable to go, and sent his nephew, George, instead, who had to report a complete failure. The reason of the failure was, that the entire Regiment, with women and children, had the itch! Jenner was then driven to the conclusion which, says Baron, “he adopted and invariably maintained to the last hour of his life, namely, that any cutaneous disease, however slight in appearance, was capable of interfering with the regular course of the Cowpox and of preventing it from exercising its full protecting influence.”[100]
Just so: and mark how the same logic applies to the Variolous Test, which “nobody could get over.” If any cutaneous disorder, however slight, could nullify Cowpox, was it not equally probable that the cutaneous disorder induced by inoculated Cowpox would nullify inoculated Smallpox until the effects of the Cowpox had time to subside? When the itch at Colchester was cured, then inoculation with Cowpox was found to be practicable. Thus worthless was the Variolous Test on Jenner’s own principle; yet with such evidence under his eyes and among his fingers, he failed to discern its significance. Nor apparently did he inquire whether the influence of Cowpox was perpetuated over specified periods of six months, nine months, one year, two years, and so on. As trader and adventurer, it suited him better to be not over inquisitive, and to avow boldly that his specific conferred life-long immunity from Smallpox.
Vaccinators at this day rarely refer to the once famous Variolous Test: to do so would be absurd. The fact of Re-Vaccination, of Vaccination after Vaccination at short intervals, proves, that whatever the influence of the operation, it is transient and not permanent; and the cases of Smallpox after Vaccination, and of Smallpox in its most malignant forms after Re-Vaccination, as if induced thereby, leave the Variolous Test, which so widely impressed and imposed upon our forefathers, an exploded piece of jugglery.