150
Mr. J. A. LePrince, C.E.A.M., Chief Sanitary Inspector, Panama Canal
Zone, states that—
" From the 31st October 1909 to 1st January 1910 during the period
" of heaviest rainfall, only 3.26 per cent. of the force (labourers) were
" hospital malaria cases."
441. Wilhehnshaven.—It is recorded that in 1896 during the construc-
tion of the harbour at Wilhelmshaven, a fearful epidemic of malaria occurred,
which affected both the workmen, the crews belonging to the shipping and the
residents in the vicinity. At this time little was known of the possibility of
preventing malaria. But during the recent enlargement of the harbour works,
special precautions were adopted from the commencement and as a result there
has been no outbreak of the disease.
442. The result of the preventive work that has been carried out at
Panama and Wilhelmshaven shows that even among aggregations of labourers
engaged upon construction work in malarious areas, the adoption of adequate
precautions is sufficient to neutralize the risk of epidemic outbreaks of malaria,
to which these temporary collections of labourers are specially liable.
443. Before concluding the chapter it may be as well to draw attention to
an objection that may possibly be raised to the carrying out of anti-anopheline
measures in Bombay, on the ground that such measures have failed at Mian
Mir, a station in India in which, as is well known, anti-malaria measures were
undertaken some years ago.
444. Mian Mir (now called Lahore Cantonment) is a military station in
the Punjab, possessed of a population of about 16,000, and covering an area
of about 8 square miles. The country in which it is situated is exceedingly
flat, and owing to the impervious nature of the soil the area is an exceedingly
difficult one to drain. In a description of Mian Mir it is stated that :—
" After one or two hours of continuous rain the appearance of the
" cantonment is changed from that of an arid plain to that of a district in
"flood. Broad expanses of water, often a quarter of a mile in extent,
" cover the plain on every side and the inhabitants of the follower's huts
" on some of the comparatively lowlying parts are literally flooded out.
"The majority of these large expanses of water dry up in the hot sun in
" three or four days, but numerous small deeper pools are left which, lasting
" for the week or ten days, form excellent breeding grounds of anopheles
" mosquitoes."
Unfortunately the anopheles mosquitoes responsible for the spread of
malaria in Mian Mir readily breed in the pools of water that form in and about
the station during the rainy season, and as these pools exist in every direction
out in the open country far beyond the limits of the Cantonment, it becomes
an almost impossible task to control the breeding of dangerous anopheles there ;
and although irrigation has been abolished and a considerable amount of
preventive work has been attempted, the results have not been satisfactory.
445. To those who do not realize that malaria is a disease almost entirely
dependent upon local conditions, the fact, that anti-anopheline measures have
failed in one place, may seem an argument against their adoption in another.
But such a view is not a reasonable one.
446. A brief comparison of the conditions relating to malaria in Mian
Mir, with those present in Bombay, is given below :—