In this case the inoculated part shews early certain marks of infection, sometimes on the very next day, or the day after, when the incision will often appear considerably inflamed and elevated. The patient about this time frequently makes some of the following complaints, viz. chillness, itchings, and small pricking pains in the part, and sometimes on the shoulder, giddiness, drowsiness, and a slight head-ach, sometimes attended with a feverish heat, but often without any: the account they themselves give of their feelings, is, in some, as if they had drank too much, and in others, as if they had caught a cold. These complaints seldom last twenty-four hours, often not so long, and with frequent remissions, and never, that I remember, rise to a degree that requires confinement. The inflammation on the arm at the time of the complaints, advances apace, and feels hard to the touch; but upon their wearing off, the inflamed appearances gradually lessen, and the part dries to a common small scab; the skin that was before red, turns livid, and the party is quite well, and nothing more heard of the distemper[2]. In some instances these symptoms attack much later; even on the seventh or eighth day, when an eruption might be expected in consequence of them, yet none appears; but the arm gets well very soon, and the disease is at an end.
In this irregular sort of the disorder there have, however, been some examples where a few eruptions have appeared, and probably in consequence of the inoculation; yet the pustules have not looked like the true pocks, nor maturated like them, nor lasted longer than three days; about which time they, for the most part, have dried away.
As I find it difficult to describe the variety and irregularity of symptoms that occur in this short way of having the distemper, I will give some cases, by way of illustrating the matter more to the reader’s satisfaction.
When subjects of this sort first occurred in my practice, I was in doubt whether they were quite secure from any future attacks of the distemper; and in order to try whether they were so or not, I inoculated them a second time, and caused them to associate with persons in every stage of the disease, and to try all other means of catching the infection; and this method has been practised with the generality of such patients ever since, yet without a single instance of its producing any disorder: so that I now make no scruple of pronouncing them perfectly safe; and experience has enabled me, for the most part, to foretell, in two or three days after the operation, when the disease will pass in this slight manner.
Upon the second inoculation, however, the incised parts are commonly inflamed for a day or two, just in the same manner as I have, in numerous instances, found them to be, as well in those who, though certain of having had the small-pox in the natural way, have submitted to be inoculated merely for the experiment sake, that the result might be observed; as in others, who, being doubtful whether they have had it or not, have been inoculated, in order to be satisfied. But in all such cases the parts soon became well; nor did any of those appearances which have been described as the constant attendants on inoculation, as pain in the head, giddiness, marks of infection in the arm, &c. ensue; nor can they ever be produced upon a person who has had the small-pox before, either in the natural way or by inoculation; and therefore it cannot with reason be suggested, that the patients, whom I suppose to get through the disease in the very slight manner above described, may possibly have had the small-pox unobserved in some former part of their lives.
Another irregularity deserving notice here, is, that sometimes, upon the abatement of the fever and other symptoms, after the appearance of several pustules, and when the eruptive stage of the disease seems completed, it nevertheless happens that fresh eruptions come out, and continue doing so daily, for 4, 5, or even 6 days successively; preceded sometimes by a slight pain in the head, though more frequently they appear without any new disturbance. These are generally few in number, short-liv’d, and seldom come to maturity. But I have seen four cases, in each of which, after a cessation of complaints, and an appearance of few pustules, the eruptive stage of the disease was thought to be over, yet in two or three days a fresh fit of fever has attacked the patients, and after a short illness a quantity of new pustules has broken out, far exceeding the first number, and these remained, and maturated completely. Instances of this kind may be found among the cases annexed[3].
Some of my own patients, and, as I am credibly informed, of other inoculators in this way, have had considerable eruptions of this kind after they have returned home; which have probably given occasion for the reports of several having had the disease again in the natural way after inoculation. But that these reports are ill-grounded, will appear from this observation, to wit, that in all the cases of this sort which have occurred in my own practice, or, as far as I can learn, in that of others, the second or latter crop of pustules has always happened within the time usually allowed for the progress of the small-pox from inoculation, and before the inflammation on the arm has ceased, and sooner than they could be supposed to be produced by infection taken in the natural way; and whenever it has happened, it has been to persons in whom, after a slight eruption, and abatement of symptoms, the disease has prematurely been judged to be quite over, and they have therefore been permitted to return to their families.
It will doubtless be asked, how cases of this kind should ever happen among those who return home as cured? To which I answer, That it is no unusual thing for industrious men, after a slight eruption, and cessation of all complaints, to ask leave to return home to their occupations and families; and where it has been thought that no danger would accrue to others, their request has been often granted; for the physician, no more than the patient, can foresee when these accidents shall follow: but it may be observed here, that in all these cases of my own knowledge, very repellent methods have been used in the beginning; and a more generous diet or greater exercise afterwards, has seemed to contribute to this secondary eruption.
Before I conclude this chapter, it may be proper to observe, that inoculated patients, in some stage or other of the disease, may possibly be attacked with diseases altogether independent of the small-pox; such, for instance, as may arise from worms, or be the epidemic of the season, or such as the patient may by constitution be subject to; and some cases of this sort will be found among those annexed.[4]