REPORT ON THE WORKING OF THE KING INSTITUTE, GUINDY
1921-22 showed a decrease of 44,946 over those of 1920-21. The net effect, there-
fore, of the cessation of hot weather vaccination in 1921-22 was that 144,475 cases
(189,421—44,946) who would under ordinary circumstances have been vaccinated
in the hot weather were transferred to the cold weather. Unfortunately, for the
further calculation, neither of the two years under consideration are normal years
so far as the success rate and the hot weather drop are concerned. In 1920-21
the drop was excessive ; in 1921-22 no definite drop occurred. A direct calcula-
tion based, on the actual success rates obtained during these two years would,
therefore, not give average results from which we could estimate the true position
of affairs. It has been considered better to take the success rates given in a
normal year such as 1918-19. In this year the success rate during the hottest
months was about 66 per cent, and during the majority of the cold months 85 per
cent.
The 347,678 cases vaccinated during the hot weather of 1920-21 would have
given 229,467 successes and 118,211 failures and the 158,257 cases vaccinated
during the same period in 1921-22, 104,450 successes and 53,807 failures.
The 144,475 cases which were left over in 1921-22 to the cold weather should
be calculated at 85 per cent and under these circumstances would give 122,804
successes and 21,671 failures. Combining the figures for 1921-22 we get the
following results for the two years :—
Year.
Total number of
cases vaccinated.
Successes.
Failures.
1920- 21
...
..
347,678
229,487
118,211
1921-22
...
...
...
302,732
227,254
75,478
44,946
2,213
42,733
There is a decrease of 44,946 cases as a result of the cessation of hot weather
vaccination. This decrease at the success rates used for the calculation would
chiefly be made up of unsuccessful cases (i.e., 42,733 cases), the net decrease in
successful cases being only a little over 2,000. The adverse effect on the vaccinal
state of the Presidency is thus negligible while the expense and trouble of carrying
out over 42,000 unsuccessful vaccinations has been saved. The moral effect of an
unsuccessful vaccination has also been removed and the full obligation to get the
case vaccinated during the colder months still remained. Cessation of routine
vaccination during the hot months has thus a beneficial effect upon the vaccination
results, and it is to be hoped that as time goes on, and the vaccination staff and the
public become accustomed to the innovation, the decrease in the annual number of
persons vaccinated which was noted this year will disappear.
Another point becomes evident as a result of the Memo. No. 8121-P.H., dated
16th May 1921 and G.O. No. 860-P.H., dated 19th July 1921. Vaccination during
these months is only carried on in the presence of smallpox. The demand for
lymph at this season may therefore be used as an indication of the presence of the
disease in the districts from which these demands come, and the quantities of
lymph supplied may also be used as a rough measure of the intensity of the
epidemic.
The vaccination returns, divided according to districts, is shown in state-
ment IV, which has been charted out as chart II. Here again the curves for
lanoline and glycerine lymph are given separately and the districts are arranged
according to the type of monsoon prevalent in them. The glycerine results from
all the districts are superior to those obtained with lanoline lymph although there
are considerable variations in the measure of success achieved in the different
districts.
The curves for the two types of lymph follow each other fairly closely but not
absolutely—for example, Tinnevelly, Nellore and Coimbatore have improved their
position in the list as far as glycerine vaccine is concerned. In Tinnevelly the
glycerine success rate is high while the lanoline rate is comparatively low.