302 REPORT OF THE LEPROSY COMMISSION:
but in the villages little at. present can be done in this direc-
tion.
Habitations necessarily vary in size with the wealth and
position of the owner or tenant. They are more generally built
of bricks and mud in the plains, of stone in the hill tracts, and
of bamboo and wood in Burma and certain parts of India. In
towns and cities they are usually placed in close proximity to
one another, and thereby efficient ventilation and air-flushing
of the site are interfered with. Overcrowding of these dwellings
is the rule, and in the hill tracts is often excessive. The
residents, however, live largely in the open air, and doors and
windows are either seldom closed, or are so carelessly con-
structed that air freely enters the house or hut.
In connection with habitations, it should be mentioned that
not only in India but also in other parts of the world the
mosquito has been much feared. As Dr. Arning says:1
" Ashmead seems to fear much the bite of the mosquito, and
I quite agree with him that the idea of transmission of leprosy
through the sting of an insect is a very plausible one." Dr.
Arning himself "frequently examined mosquitoes bacterio-
scopically, which were found inside the mosquito nets of beds
containing cases of severe cutaneous leprosy. He caught the
insects when they were quite full of the blood sucked from the
patients. He never discovered any trace of leprosy bacilli,
either in or upon them." Some members of the Commission
examined flies and mosquitoes, but also with negative result,
as will be seen from the Laboratory Report. Other consider-
ations, however, make it appear extremely unlikely that a
propagation of the disease should be due to these insects. It
is hardly possible that the toxic principle of the mosquito should
contain bacilli, even though they be present in the blood with
which the insect is gorged. Again, cases of transmission from
patients to hospital or asylum officials should be very common
(1) Journal of the Leprosy Investigation Committee, No 2, February 1891. page
132.