REPORT OF THE KING INSTITUTE, GUINDY

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issue from cold store, and this deterioration is diminished when only a few cases
have to be done, because then the vaccine is used up on the first day. It is to be
noted that April's figures for numbers vaccinated distinctly exceeded those of the
other off-season months.

        The district success rates are given in Table V. The Nilgiris have the best
results with a case success rate of 99.7. Good results were obtained by Madras
(99.1), Chittoor (99) and Malabar (98.9). In the following districts the case
success rate is below 95 per cent:—

        It is instructive to compare the results for the twenty-five districts for the
last three years since glycerine lymph has been issued. Judging by case success
the best districts in order of success are as follows:—

            1923-24.Nilgiris, Chittoor, North Arcot, Madras and south Kanara
bracketted equal, Malabar.

            1924-25. Nilgiris, Chittoor, Madras, Malabar, South Kanara.

            1925-26. Nilgiris, Madras, Chittoor, Malabar, North Arcot.

        The worst districts in order of lack of success are as follows:—

            1923-24. Vizagapatam, Kurnool, Rāmnād Gōdāvari.

            1924-25. Kurnool, Vizagapatam, Bellary, Cuddapah.

            1925-26. Vizagapatam, Rāmnād, Guntur, Kurnool.

        The persistence with which districts tend to give the best or worst results,
particularly the former, is apparent. Apart from variations in vaccinators the
chief factors concerned in the results are probably those that affect deterioration
of vaccine. These are (1) distance from this Institute affecting the time of journey
of the vaccine and so its exposure to atmospheric temperatures, (2) local climate
affecting the vaccine while in the vaccinators' hands and probably directly affect-
ing the actual " taking " of a vaccination by its effect on the skin, (3) local
communications affecting the celerity with which vaccine can be used up. Thus
the success of the Nilgiris despite its distance is to be mainly attributed to the
factor of a cool climate. We have evidence that coolness affects vaccination by
its effect on the skin, in that vaccinated rabbits give better results when kept
in a cold room at 58° F. than when kept at ordinary temperatures. The success
of Madras, Chittoor and North Arcot is attributable to the first factor—proximity.
Vizagapatam and Kurnool illustrate the. adverse effect of distance.

        These considerations are important as indicating possible future lines of
advance in combating conditions (1) and (3). Thus distance can be overcome by
opening a local cold store to which lymph would be sent in ice.

        11. Revaccinations.—Details for months and districts are given in Tables VI
and VII which call for no remark except that the total revaccinations this year
are a little more (by about 40,000) than those done last year.

        12. Saidapet Range.—Before issue elsewhere all strains of lymph were issued
to the local vaccination range and results recorded. In 5,375 primary vaccina-
tions a case success rate of 99.3 and an insertion success rate of 97.3 were
obtained. These high rates are probably due to the factor of proximity
mentioned in paragraph 10.

(B)GENERAL BACTERIOLOGICAL WORK.

        1. Stock, vaccines.—Table VIII gives full details. The total number of doses.
issued is 85,569 which is about 20,000 less than last year. This decrease is due
to 20,000 less doses of cholera vaccine having been indented for. The influenza
vaccine issued this year was less than last year's by about 4,000 doses but this is
balanced by the mixed typhoid T.A.B. vaccine being about 4,000 more.

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