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Now to go to the 108 cases of small-pox examined by me for signs of successful
vaccination. Of these 73 had certainly never been vaccinated, 27 had been vaccinated,
and in 8 cases the persons affected were stated to have been vaccinated; but after careful
search I could find no marks. However, as there is an element of doubt in these cases,
I have omitted them from the following deductions.

Among 100 people affected, 73 per cent. had never been vaccinated, and of these
26 had the disease mildly, 22 had a moderate attack, i.e., neither severe nor very mild, in
fact, had the disease in a typical form. The remaining 23 had the disease severely, and
10 of these in the " confluent " form (one was a case of "malignant small-pox," there being
hæmorrhages into the vesicles. The child died shortly after I saw it). This grouping
is done simply on observations made at one visit, and is cheifly taken from the character
of the rash. I, of course, had no opportunity of watching the disease throughout. I could
only see the cases when passing through affected villages. And I have also been unable,
up to the present, to get the number of deaths. But so far as my observations go, they
show that among the unvaccinated this year about one-third had the disease mildly, one
third had it severely, and the remaining one third had the disease in a form which we may
call "moderately" for want of a better term.

Turning to the vaccinated cases, I find that 23 out of the 27, or 85 per cent., had
the disease in a mild form ; 2, or 7 per cent., had a moderate attack ; and 2, or 7 per cent.,
had the disease in a severe form. From this we see that not only does vaccination protect
most people against small-pox, but also that those who afterwards contract the disease,
85 per cent. get only a mild attack. Some of these were so mild that I have recorded in
my notes that " only a few spots appeared." Of the 2 cases which had the disease badly,
one had been vaccinated 23½ years ago, and the others 7½ years ago.

Looking at these cases from another point of view, 1 child (already noted in the
table) got the disease a year after vaccination, 2 after 3 years, 2 after 5 years, 1 after 6
years, 4 after 7 years, 2 after 9 years, 1 after 10 years, and the remaining 11 after 11 years.

I have not recorded dates in 3 cases, but as the children were all over 8 years of age,
it is probable that they were all vaccinated more than 7 years ago. Omitting these last
cases, we may make three groups; (1) those vaccinated within the last 5 years, when buffalo
lymph has been exclusively used in the districts under consideration; (2) those between
5 and 7, when they may or may not have been vaccinated with buffalo calf lymph, and,
lastly, those over 7 years, who must have been vaccinated with human lymph. In the first
group we have 3 cases; all had the disease very mildly, and in two the notes record that
the marks were very indistinct. In the third case the character of the marks is not stated.
I therefore presume they were distinct. In the second group (between 5 and 7 years since
vaccination) 2 cases had the disease very mildly (only a few spots in each case), one
had a moderate rash, and the third had a severe attack. In every case the marks of vac-
cination are stated as being "faint " or "very faint." After this date the attacks from
small-pox get more frequent, but as all acknowledge that re-vaccination becomes necessary
after this time, and as the vaccinations were done with human lymph, the efficacy of
which few will contest, I need not go into details. I think I may safely draw the conclu-
sion that buffalo calf is protective for some time from the fact that I have seen many
cases of small-pox and found only 3 cases which got the disease after vaccination with
buffalo calf lymph, and these were all probably badly vaccinated as shewn by the indis-
tinctness of the marks, and yet all had the disease very mildly.

Perhaps my strongest point is the following. I visited 23 houses where there was
small-pox present, and noted what other children were living in the same buildings,
and whether or not they had been vaccinated. I found 78 children altogether, of
whom 40 had, some time or other, been vaccinated; only 2 got small-pox. Of the
remaining 38 who had not been vaccinated, 28 got the disease, and only 10 escaped.
In one house 1 child out of 6 had not been vaccinated. It got the disease, and the rest
escaped. In another house 1 out of 5 children had not been vaccinated, and was the
only one who contracted the disease. In a third house, that of a Khatri Sikh, none out of
5 children had been vaccinated. They all got small-pox.

When I first started inspecting cases of small-pox, I did not take notes, and even
afterwards my notes were not very complete. All these cases have been eliminated for
want of sufficient and exact information. Those recorded afterwards were taken in
the order seen by me. I have used no other selection except those mentioned in the
preceding paragraphs. I had no intention at first of publishing these cases, but the in-
formation seems to me so definite, and as people have expressed doubts as to the efficacy
of vaccination among natives, I have thought it necessary to give my results. There is
nothing new about the investigations, except, perhaps, that they have not before been
applied to buffalo-calf vaccination. This, I believe, is the first direct investigation that
has been attempted to determine the prophylactic power of buffalo calf lymph, and it is
very consoling to find that we are using so powerful and effective an agency to protect us
from a disease justly dreaded as being one of the worst ills to which the human race is
liable.