National Geographic : 1944 Feb
Saboteur Mosquitoes BY HARRY H. STAGE * IN WAR ZONE dispatches of your daily newspaper, you read of the mighty influ ence of a winged "fifth column." Common traitor to all people, in all climes, the mosquito army has won and lost battles and turned the course of history many times through the centuries. First of enemy powers to take to the air, mosquitoes are serving as a "ferry command" to carry malaria, yellow fever, filariasis, den gue, and other diseases to our men.f As ever, the female of the species is dead lier than the male. By her artful, persistent tactics, she can lay low our fighting strength. In some highly malarial areas, if troops are unprotected from mosquito bites for a single night, 20 percent of them will develop ma laria. Neglected a second night, another 10 percent will be incapacitated. Just history repeating itself! Mosquitoes Attacked Caesar, Napoleon Julius Caesar's army suffered much from malaria during the Roman civil wars. One observer wrote: "The unhealthy autumn spent in Apulia and near Brindisi had shattered the health of Caesar's whole army, which came from the un usually healthy regions of Gallia and Spain." Napoleon's forces were ravaged by malaria. The disease ran rampant during the Chino Japanese War of 1894-95. It was responsible for more than 5,000 deaths during the Span ish-American War. Malaria dealt 'a terrific blow to British, French, and German troops alike in Mace donia during World War I. Campaigns were stalemated for months because troops of all nations were immobilized. From 1916 to 1918, among 124,000 British troops, there were 162,000 admissions to hospitals for malaria. Many of the patients re-entered sev eral times. This epidemic was one of the biggest medi cal surprises of the war, for virulent cases originated not only in low swamp country near the coast, but in mountains from 5,000 to 6,000 feet above sea level. Not until a decade later was the mystery solved. Then Dr. Lewis W. Hackett, of the Rockefeller Foundation, and several European entomologists found seven distinct subspecies of Anopheles maculipennis in the Mediterra nean area. Three of them, which breed in brackish coastal waters, carry malaria. That explained the presence of the disease along the coast. Four others which do not carry ma- laria live in the hill country and breed in fresh water. But the entomologists found another species, Anopheles superpictus, which breeds in the pure waters of the hills and mountains, and is a dangerous malaria carrier. This was the mosquito responsible for the spread of the dis ease in the hill country. The Italians failed to profit by this valu able discovery when they invaded Albania in 1939. To keep their troops from contracting malaria, they sent them into the hills, and Anopheles superpictus went to work on them. More than one enemy has been deceived by this "paradoxical malaria." Fighting Japs, Germans, and-Mosquitoes! In the Philippines, our Army tried to cut down malaria by encamping on high ground, only to find a hill-stream breeder, Anopheles minimus, which at once infected our troops there. Our men now in military service face an enemy as cunning and formidable as the Axis. Although the mosquito lines may be broken, they are rarely wiped out. The Army, Navy, and Public Health Serv ice control malaria in and about cantonments within the United States through drainage, filling, screening, and the use of larvicides and sprays. In foreign lands such permanent control measures are not always feasible. The indi vidual fighter must take certain precautions to protect himself. Wherever malaria is prev alent, he must avoid native towns after dusk, he must be exceedingly careful to arrange his bed net so no mosquito can touch him, and he must use mosquito repellents and other devices which our Government gives him. In training, a soldier learns what to do, but in times of stress he may disregard the lowly mosquito and soon find himself a lia bility to his comrades. Returning officers tell me that a friend of mine, Maj. Fred T. Bishopp, of the U. S. Marine Corps, side-stepped malaria for months while on Guadalcanal. Practically every other member of his battery was afflicted with the disease. Major Bishopp's physical equipment was * Senior Entomologist, Bureau of Entomology and Plant Quarantine, Agricultural Research Administra tion, United States Department of Agriculture. t See "Healing Arts in Global War," by Albert W. Atwood, NATIONAL GEOGRAPHIC MAGAZINE, Novem ber, 1943.