12
RE PORT OF THE KING INSTITUTE, GUINDY
Surgeon M. K. Ramaswami Ayyar went to Mopad in November 1926 which
ordinarily is the period just after the north-east monsoon. But this year not only
had the south-west monsoon from July to September been poor, but in October
and November the north-east monsoon—the principal monsoon in these parts had
almost completely failed, yielding only 3.09 inches of rain as compared with the
previous decennial average of 16 inches. Despite this the conditions were very
favourable for malaria. Mosquitoes were so abundant that they were described
as being present in clouds. The total caught was 969, and of these as much as
674 or 70 per cent were malaria carrying anophelines—A. culicifacies, A.
stephensi and A. listoni. Anopheline breeding conditions were about the same
as in March, i.e., abundant everywhere particularly in the bed of the Manneru
river, but in many places the sub-soil water level was lower than in March so that
the water facilities were on the whole less than in March. Excessive irrigation
water-logs the soil and so water for breeding is present practically all the year
round. The great difference between the adult anopheline populations in March
and November without any change in the collections of water available for breeding
is a very good illustration of the fact that seasonal and monsoon changes act not
only by providing water collections for breeding, but also largely by the associated
conditions of temperatures and humidity being favourable for the life of adult
anophelines. The recommendation made was that an Engineer’s opinion be
obtained on the probable effect on the Manneru river bed below the dam of
reverting to dry crop irrigation in the Mopad area, because it was thought though
this type of irrigation instead of the present wet crop irrigation would largely
diminish the number of anopheline breeding places throughout the area, yet unless
the extensive breeding places in the Manneru river bed were also eliminated
severe malaria would continue.
4. Second malarial surveys of Udayagiri and Duttalur.—These were made
in December 1926 by the same unit as in (3) above. Owing to the failure of the
north-east monsoon, conditions were not very favourable for malaria, so there was
no severe epidemic. In Udayagiri disused wells were found to be maintaining
a supply of the chief anopheline malaria carrier—A. culicifacies.
5. Malarial survey of Bimilipatam.—A malarial survey of Bimilipatam
was made by the same unit as in (3) above. This town has recently suffered
rather severely from malaria and malignant tertian was the main variety. A.
culicifacies appeared to be the chief carrier. The most important breeding places
were disused wells and recommendations were made accordingly.
6. Malarial survey of Hospet.—A Unit was sent in October 1926, a
favourable season of the year but had to return on account of a severe outbreak
of plague in Hospet. Another unit under Assistant Surgeon M. K. Ramaswami
Ayyar went to Hospet in March 1927. As a result of its work it was recom-
mended that subject to confirmation of the findings by a second visit in autumn,
an extension of the town towards the Roya Channel should not be permitted and
that the Basavanna channel extension be allowed to continue so long as sub-soil
leakage from it was prevented and irrigation from it within municipal limits was
forbidden.
7. A rapid search for the main mosquito breeding areas in the City of
Madras.—Following complaints by the public of a mosquito nuisance in Madras, in
February 1927, a search for breeding places was made by a unit under Assistant
Surgeon K. V. Venkataraman. The mosquitoes were mainly culicines and A.rossi.
The chief breeding areas were found to be (1) the northern city portion of the
Buckingham Canal, (2) the swamps about Basin Bridge and the adjacent railway
lines, (3) small areas in the bed of the Cooum, (4) the Otteri Nullah, (5) the
Medavakam and other tanks, (6) large open drains in the city, and (7) a number
of disused wells.
8. Malarial survey of Vizagapatam Municipality.—The same unit as in
(7) above started work in March 1927. A summary of the findings will be given
in the next year’s report.