THE New Zealand Herald AND DAILY SOUTHERN CROSS SATURDAY, FEBRUARY 25, 1933 A SPREADING MENACE

New Zealand Herald, Volume LXX, Issue 21426, 25 February 1933, Page 10

THE New Zealand Herald AND DAILY SOUTHERN CROSS SATURDAY, FEBRUARY 25, 1933 A SPREADING MENACE

Again the attention of the world has been called to the menace of a tiny gnat—that sort of blood-suck-ing fly known commonly as the mosquito. Experts in the Ross Institute are perturbed, it is reported, at the risk of the spread of yellow fever by aeroplane traffic across vast spaces. Primarily they are concerned about infection from West Africa, a region of evil repute in this kind of disease, and their researches have demonstrated the possibility of aircraft becoming "carriers." Infected mosquitoes, while in their period of incubation, which lasts sometimes as long as three months, may be thus transferred ; experiments prove that 22 per cent survive a journey of 1250 miles. Thus a new terror has appeared with the progress of aviation. It is inadequately realised that this terror, apart from the fear now added by this development, is altogether so new that less than thirtyfive years ago little was known or even suspected of the ravages of this pest. Before 1899 entomologists were not sufficiently concerned to pay attention to it, and only a handful of species was classified. Then an almost sudden change of attitude happened, thanks to the investigations of Boss in India and of Grassi in Italy, each of them working in a field heavily infested. They found that mosquitoes were the agents in the dissemination of malaria, and speedily they had the ratifying witness of research workers in almost all parts of the world. As a result, nearly 2000 species are now known, and the particularly deadly Anopheles, in comparison with the less dangerous but not negligible Culex, is under special note as a terrible menace to human life. Modern as is this discovery, there is no doubt that for unreckoned centuries physical havoc has been wrought over a wide range, and more than one expert has seriously advanced and argued the opinion that ancient Mediterranean civilisations were undermined by this havoc. Now that the aeronautic arrow that flies by day is suspected of serving the pestilence that walks in darkness, it behoves every nation to take adequate precaution. The story of heroic campaigning against this assault on human welfare is one of the most thrilling romances of medical science. Men have hazarded their reputations, their health, even their lives, to repel and conquer the menace. "Crazy Pat Manson," discoursing in season and out of season about the life-round of filarial worms, did much to prepare the way for Ross. Both these British enthusiasts suffered much as well as achieved much in the course of their unflagging service. When practical efforts followed, as they did with remarkable celerity, in different parts of the world—before honour in the form of knightly titles came to these two British pioneers—the tale of zeal and heroism grew apace. Sir Ronald Ross was righteously vexed at the dilatoriness of British officials abroad, especially the authorities of the Crown Colonies, in putting preventive measures in operation, but his "Mosquito Brigades," published in 1901, aroused a passion of effort elsewhere. Soon the Johns Hopkins University in the United States became a centre of splendid earnestness about the crusade Ross preached. His explicit directions, based on his own arduout field-work, inspired campaign after campaign in the tropics. In. Cuba, where sanitary conditions were shockingly bad at the time of the United States' war with Spain, malaria was rife and an epidemic of yellow fever among the American troops in occupation was greatly feared. A roll of honour commemorates the service of many medical men in that crisis—Thayer, Lazear. Carroll and Walter Reed, with Sternberg and Agramonte. They proceeded on the earlier theory of. Finlay, a Cuban physician, and the confirmation it had in famous Italian, laboratories as well as in the fieldwork of Ross: and they achieved a triumph. What happened similarly in the Panama Canal Zone, with which the name of Gorgas will ever be honourably associated, is well known.

In spite, however, of all such facts and their lessons, a widespread carelessness prevails, and tho anxiety marking the appeal of the Ross Institute experts, expressed pointedly in the practical appeal of so great an authority on tropical hygiene as Sir Malcolm Watson, is too well grounded to lack warrant. His suggested permanent committee is designed to cover all the British Dominions—a point that, ought not to be lost on New Zealand. West Africa, it, is true, is a special focus of anxious interest; it has long been a region in which British investigators have been glad of the wise and munificent aid of the Rockefeller Institute. But the habitat of Ihe mosquito—and it should not be forgotten that the malarial Culex is to be dreaded only less than the yellow-fever Anopheles—is practically worldwide: some species have been found even in polar tracts. This country is not immune, although it is almost free as yet from the worst forms of the pest, and local authorities should be ever vigilant, in co-operation with the Health Department, to combat the threat of worse harm than has yet been suffered. There has been abundant forewarning and some action, but the risk is inadequately met. To leave no stone unturned — which in this connection means much more than the turning of stones, although many things as simple—is a plain duty. Advice on practical means is sufficient. To act thoroughly on it is gravely advisable.