To Mr. Dunning he wrote from Cheltenham, October 25th, 1804—
How frequently does the Vaccine Disease become entangled with herpes! I see that the herpetic fluid is one of those morbid poisons which the human body generates, and when generated, that it may be perpetuated by contact. Children who feed on trash at this season of the year are apt to get distended bellies, and on them it often appears about the lips. This is the most familiar example that I know. A single vesicle is capable of deranging the action of the vaccine pustule. Subdue it, and all goes on correctly.[199]
And again to the same correspondent, 23rd December, 1804—
My opinion is that the chief interference with the success of Vaccination is herpes in some form or another. I have discovered that it is a very Proteus, assuming as it thinks fit the character of the greater part of the irritative eruptions that assail us.[200]
Having thus detected an all-sufficient explanation of the failure of vaccination to prevent smallpox, he communicated his discovery to the Medical and Physical Journal, August, 1804, in a paper entitled, “On the Varieties and Modifications of the Vaccine Pustule occasioned by an Herpetic State of the Skin,” but he complained to Dunning “that it seemed not to have excited the slightest interest.” In order to call attention afresh to the subject, he had the article reprinted as a pamphlet at Cheltenham in 1806 and at Gloucester in 1819, but in vain. He complained to Baron in 1817 that he could not get the Board of the National Vaccine Establishment to attend to his cautions touching the interference of cutaneous diseases with the progress of the vaccine vesicle. “I am afraid,” he observed, “that the extreme ignorance of medical men on this subject will destroy the advantages which the world ought to derive from the practice.”[201]
What of course medical men with the least common sense perceived was, that the excuse provided for vaccination failures was too liberal to be worth anything. If the least cutaneous eruption was sufficient to frustrate vaccination, what operation could be pronounced efficient? for it could scarcely be intended that every patient should be stripped to the skin and minutely examined for herpetic vesicles. There was nothing transitory in Jenner’s opinion about herpes: he harped upon its mischiefs and omnipresence to the close of his life. William Dillwyn of Walthamstow having asked him for any observations that occurred to him on the practice of vaccination for the benefit of Friends in Philadelphia, Jenner replied in a letter dated Berkeley, 19th August, 1818, in which we find these remarks—
I must candidly acknowledge that I am not at all surprised that a partial prejudice should now and then lift up its head against Vaccination. It is called into existence, not from anything faulty in the principle, but from its wrong and injudicious application. For example, a child, or family of children, may be in such a state, that the action of the vaccine fluid when applied to the skin shall be either wholly or partially resisted. It may either produce no effect at all, or it may produce pustules varying considerably in their rise, progress and general appearance from those which have been designated correct. It was about the year 1804 that I was fortunate enough to discover the general cause of these deviations, and no sooner was it fully impressed on my mind, than I published it to the world. Yet few, very few indeed, among those who vaccinate, have paid any attention to it; yet I am confident, from the review of the practice on an immense scale, that it is a matter which has a greater claim on our attention than any one thing besides connected with Vaccination—indeed I may say than any other thing. What I allude to is a coincident eruptive state of the skin, principally bearing what we call the herpetic or eruptive character. If we vaccinate a child under its influence, we are apt to create confusion. The pustule will participate in the character of the herpetic blotch, and the two thus become blended, forming an appearance that is neither vaccine nor herpetic; but the worst of it is that the patient does not receive that perfect security from Smallpox infection which is given by the perfect pustule.[202]
These complaints of the indifference of the medical world to his prophesying, show how completely the business of vaccination had passed out of Jenner’s hands. The influence of herpes on vaccination, although declared by him to be of the utmost importance, even to the extent of imperilling the advantages of the practice, was disregarded as unworthy of serious attention.
Another of Jenner’s apologetics was a pamphlet in 1808[203] designed to explain away the failure of the variolous test—the test that deceived so many in the early days of vaccination. The inoculated with cowpox were inoculated with smallpox, and when the smallpox did not “take,” it was said, “Behold the perfect protection!” The smallpox inoculators complained bitterly of the hocus-pocus. “No wonder,” they said, “that when the system is in a fever with bestial corruption, that human pox will not ‘take,’ but try after awhile.” And they did try after awhile, and it was found that the vaccinated could be inoculated with smallpox like the unvaccinated. Indeed, when it was seen that the vaccinated fell victims to smallpox, many who had been vaccinated resorted to the smallpox inoculators for their supposed superior protection, and received it without hindrance from their previous vaccination. It therefore became judicious to disown the variolous test; but neither in this case was the surrender frankly made, but with prevarication that deprived it of all grace. What the smallpox inoculators maintained, Jenner had to allow, but after this fashion—
My principal object is to guard those who may think fit to inoculate with variolous matter after Vaccination from unnecessary alarms; a pustule may sometimes be thus excited, as on those who have previously gone through Smallpox; febrile action in the constitution may follow; and, as has been exemplified, a slight eruption.