INSTITUTE OF PUBLIC HEALTH, RANGOON, FOR THE YEAR 1936.

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19 times in the 367 samples of water bacteriologically examined, and
in the majority of cases there was some indication of pollution of the
water source with alvine discharges of either human beings or cattle or
wild animals. Whether this organism is present in bird droppings has
still got to be proved. The presence of B. Schafferi in a certain water
sample to which birds only had access, strongly suggests the likelihood
of this organism being present in bird droppings. Experiments were
carried out on two different lines to find the resistance of this organisms
to sunlight.

          EXPERIMENT I.—Two sets of flasks, one containing sterilised
distilled water and another containing sterilised pond water were
inoculated with saline emulsion of 24 hours agar culture of B. Schafferi.
The mouths of the flasks were covered with pieces of gauze and the
flasks were exposed to sunlight for a fortnight. The samples of water
were then tested and B. Schafferi was not recovered. The test was
repeated after an interval of another fortnight and the same negative
result obtained.

          EXPERIMENT II.—A second experiment was repeated in one of the
fish breeding chambers of this Institute. The samples of water from
the chamber were first tested to determine the nature of the lactose
fermentors that were already present there. After ascertaining that
B. Schafferi was not present in the chamber, 100 c.c. of saline emul-
sion of B. Schafferi, each c.c. containing approximately 10,000 million
organisms were introduced into the chamber on the 20th May 1936. It
must be noted that during the course of this experiment, there was rain
almost every day with very little sunlight. After an interval of a week
the sample of water was tested and B. Schafferi was recovered.

          The test was repeated on 14th July 1936 and 29th July 1936. On
neither of these occasions was B. Schafferi isolated. The above
experiments corroborate the findings of Clemesha.

V. To find out the efficacy of a proprietary product as a rat destructor.

          On 29th April 1936, the Port Health Officer, Rangoon, brought a
bottle of Liverpool Virus (a proprietary product) and asked us to find
out its efficacy as a rat destructor. An experiment was carried out on
the same lines as has been described in last year's report with the
exception that the food for the rats under this experiment was placed
on the floor of the cage instead of in a receptacle. The idea of doing
this was to give an enhanced chance of starting an epizootic through
the contamination of the food by the faeces of infected rats. As in
last year, this year's experiment also failed to produce an epizootic
among the experimental rats. Two sets of experiments were carried
out.

          EXPERIMENT No. 1.—Two Mus. Concolor were fed with food mixed
with the liquid supposed to contain Liverpool Virus. They were then