MALARIA PEST.

Auckland Star, Volume LIX, Issue 268, 12 November 1928, Page 3

MALARIA PEST.

PALESTINE NOW FREE.

SEVEN YEARS' FIGHT ENA,

EXTERMINATION* OF DISEASE

CARRYING MOSQUITOES,

Along the storied River Jordan, in . the hills of Judea and beside the Sea of j Galilee, a signal victory of modern science has just been won. One of the j oldest civilisations of the world is emerging from seven under the bacteriological microscope, with freedom from its ancient scource of malana almost in sight. In the mud huts of the Arabs and the black tents of the Bedouins, little changed from Biblical times, have come the insect-dcstroying smudge of fumigation, the formaline spray and the hypodermic needle of the doctor. Here and there the Jordan rolls under a mantle of Paris green, and timehonoured cisterns and water holes in Galilee and Samaria brim under a protective film of oil products. Crooked water courses are being made straight and swamps that menaced life from time immemorial are bein<* drained out of existence.

Dr. I. J. Kligler is now director of the Department of Hygiene in the Hebrew University of Jerusalem. With him have been working entomologists of the Rockefeller International Health Board and the Malaria Research Unit, supported by the American-Jewish Joint Distribution Committee.

Disease Spread Quickly. Palestine has always provided clouds of mosquitoes that carry the disease from one population to the other. How effectively they have done so may be seen from the fact that in 1921, before control measures began, 64.7 per cent of the new settlers developed malaria within a year of their arrival. When Dr. Kligler came to Palestine in 1921, at first under the auspices of the Hadassah Medical Organisation, and subsequently under the Palestine Health Department, he did not launch a mass attack on mosquitoes, but made a survey and analysis to see where his real foes lay. From the start he organised a kind of natural history expedition among the mosquitoes of the Holy Land, as exciting to the hunters and more important to the longevity of the inhabitants than an expedition to identify wild animals in Africa. Dr. Kligler and the co-operating entomologists of the Rockefeller Board soon knew accurately the habits of local mosquitoes.

There were, thev discovered, some eight varieties of mosquitoes in Palestine, four of them important as malaria carriers. One of these four bred only in cisterns and confined its operations to cities. Of the three which attacked the country dwellers, one bred only in stagnant, overgrown pools, another in sluggish streams and the third mainly in steadily running water.

Tbo species, moreover, were often localised in different parts of the conntry and their breeding seasons were found to be different. In one region the war would have to be carried on chiefly against overgrown streams, in another against leaky irrigation canals,

and at different times of the year, according to the principal mwquito type.

The distance the Palestine mosquito will fly for human prey was another amazing discovery. Heretofore it bad' been assumed that mosquitoes will not go more than a mile from home. In Palestine it was found that they will fly almost four miles, especially in the fall during their hibernating flight. Indeed, at that time not only do the mosquitoes fly out. in all directions from their swamp till tliey reach the nearest settlement, but often pass from village to village, spreading over large areas previously free from malaria. In the fall, too, when the Bedouins strike their tents to go south, clouds of mosquitoes are uncovered and ejected from their homes, and sometimes have to fly long distances to find new shelter. Thus malaria epidemics may occur miles from the mosquitoes' swamp of origin.

Dislike High Winds. Contrary also to the ordinary assumption it was found that mosquitoes did not invade new territory when the wind was strong, but came rather when it was gentle or had altogether subsided. When a violent wind was blowing, mosquitoes remained under cover till it passed over. Armed with these facts, Dr. Kligle.r and his associates then set out in certain regions to clean up the specific water courses in which malarial mosquitoes bred. They experimented with all sorts of methods. Best of all they found the mechanical—that is, the actual cleaning and drying out of stagnant pools and, with flowing streams, either by damming or by deflecting their course for a few days. This was the only means, they found, that gave sure results. Whole swamps have now been cleared out in various part of Palestine by variation on this method. New stream courses have been dug in some places to with the pools caused by rockerosjon in the old stream beds. In others subsoil tile drains carry off the water. In still other cases, sea water, in which most malaria-carrying mosquitoes do not breed, has been let into blocked river mouths.

In places where such drastic measures could not be taken, the experimenters used various chemicals. First, of course, they tried oil. Fov the

windblown, overgrown pools of Palestine they evolved an effective mixture of kerosene, heavy motor oil and castor oil. Still more fatal to the larvae of the malaria-carrying mosquito, though powerless against the ordinary variety, they found Paris green. This, mixed with road dust, they sprayed over swamps and pools and found it superior to oiling and three times as chcap. In four years the rate of malaria, occurrence among the Jewish population as a whole was cut from 50.4 per thousand to 8.4 per thousand. Whole villages of invalids have, as if by a miracle, regained buoyant health. In the Jewish settlements malaria is no longer looked upon as a scourge, but as a preventable disease. Colonizing agencies also are coming to see that it is neither sound eeonomics nor psychology, to say nothing of hygiene, to settle people in lands that have not been made malaria proof.