Brian P.PaceMA, Assistant Editor
R. Koch, who has just returned to Germany, devoted much of his two years in South Africa to a study of tropical malaria, which he considers resembles in many respects the Texas fever of animals and is, like that, conveyed by an intermediate agent, the tick in one and the mosquito in the other, but he has proved that the contagion is transmitted in the eggs of each, as well as by the insect itself. His most important achievement is his discovery of the exact temperature curve of tropical malarial fever. The temperature first rises and remains at this height for about half the length of the attack; then falls somewhat, returning abruptly to its former height, where it remains for the other half of the attack, which lasts about thirty-six hours in all, then rapidly falling to normal. The usual blind administration of quinin at regular intervals is absolutely useless. Quinin does not kill the plasmodium; it merely checks its development. We know now the exact moment when to administer it to produce the desired effect, which is the stage in the development of the plasmodium that precedes sporulation. Quinin at the right moment cures tropical malaria even in its worst forms. Koch confirmed this assumption in every case except two moribund. Draining swamps, planting eucalyptus, sanitoria, etc., are ineffectual prophylactic measures. The only effective measures are to keep mosquitoes away and out of residences (there is an island off the coast which is free from mosquitoes, and malaria is unknown there), and send scientific physicians to administer quinin at the proper moment. He adds that ten to fourteen days must elapse after infection before the plasmodia accumulate sufficiently to produce an attack. He considers the quotidian form the manifestation of two superposed tertian forms. He found four varieties of tropical malarial fever; two very rare; the third is the kind experienced in temperate countries, which occurs in 10 per cent of the cases there, and the fourth, or very severe kind, in 90 per cent. He is convinced that the problem of artificial immunity will be solved in time, reasoning from the natural inherited immunity of the coast negroes and the acquired immunity of the negroes who, coming from the mosquitoless mountains down to the coast, pass through a severe attack and are immune afterward, like animals who have passed through an attack of Texas fever in youth when it is usually mild.—Deut. Med. Woch., June 16.
NEW LIGHT ON MALARIA.. JAMA. 1998;280(4):322. doi:10.1001/jama.280.4.322-JJY80023-1-2