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I. RESEARCHES.
(a) Plague.—Founded- originally as a plague research laboratory, it has
specialised in research into various problems connected with plague. It
was here that Haffkine originated the technique of the preparation of his
plague vaccine and later the . British Plague Research Commission worked
out the whole question of transmission of plague and showed by a series of
masterly researches that the disease is primarily an epizootic of rats and
is . transmitted from them to man by the agency of rat-fleas. Researches
have been continued into the epidemiology of plague to further elucidate
the factors involved and the steps needed for combating epidemics of plague.
More recently work of equally far-reaching character has been carried out
resulting in the development of a biological method for the standardisation
of plague vaccine, and constitutes the first instance of a successful adequate
standardisation of a bacterial antigen in medicine. In the past lack of such
a method had led to very contradictory opinions being put forward by
different workers with regard to the preparation of plague vaccine, No
data were available from which it could be decided what type of vaccine
was the best, and what methods should be followed for its preparation.
To re-solve this difficulty work was begun to develop methods for accurately
measuring the virulence of plague cultures and the selection of the most
suitable test laboratory animal. This work led to the development of an
exact biological method for standardisation of plague, vaccine with every.
condition fully standardised so that the method could be employed by
any worker anywhere and would yield directly comparable results. This
is the first instance of successful standardisation of bacterial antigen and
marks an important advance in plague work.
This advance in knowledge has had immediate practical results. It
has enabled the protective power of the Haffkine plague vaccine to be raised
30 fold and more. Exact experiments show that now the Haffkine vaccine
is anywhere from 8 to 100 times more potent than other plague vaccines in
the market.
This method has also enabled the Institute to shed very valuable light on
the relative merits of vaccines made from heat-killed cultures and those
made from live avirulent cultures.
The new knowledge of the characters of B. pestis prompted fresh
efforts at producing a curative serum against plague. The Institute has
succeeded in producing a serum with which in laboratory experiments 70
to 80 percent of infected laboratory animals can be saved. Owing to
Lack of opportunities the value of the serum has not been put to test in
the field, except for a small trial where encouraging results were obtained.
Further researches on serology, ,histo-pathology, chemo-therapy,
epidemiology of plague etc., are in progress.
(b) Relapsing fever.—In 1906 the body louse was proved to be the natural
carrier of relapsing fever. This successful piece of work set the seal on the
observations made 20 years previously on the clinical aspects of this disease
by Vandyk Carter.
(c) Guinea-worm disease.—Notable researches have been carried out
on the nature, history and transmission of guinea-worm which was proved
to be carried from one man to another by the agency of cyclops, which infect,
wells of this presidency. These studies have resulted in the elaboration of