Medicine: Anopheles gambiae

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"If Orson Welles, in his now famous broadcast of October 30. 1938, had announced not that the Martians had landed in New Jersey, but that a mosquito called Anopheles gambiae, a native of Africa, had arrived on the American continent, there would have been no public alarm. . . . But Anopheles gambiae is potentially a much more dangerous invader than the Martians would have been. H. G. Wells's Martians, it will be remembered, were unable to adjust themselves to life on this planet and quickly died."

Thus wrote Lawyer Raymond Blaine Fosdick, president of the Rockefeller Foundation, in his review of the Foundation's work for 1938, which was published last week. Anopheles gambiae, continued Mr. Fosdick, is "the most dangerous member of a dangerous family": the malaria mosquitoes. Native home of the gambiae is Central Africa, but about nine years ago they crossed the Atlantic presumably in a French airplane which flew from Dakar in West Africa, to Natal in Brazil. They were spotted by Dr. Raymond Corbett Shannon, a member of the Foundation's staff. Within a year they had flown with the prevailing winds 115 miles up the coast.

Last year, in the Jaguaribe River Valley of eastern Brazil, the gambiae spread more than 50,000 cases of malaria. In certain districts the mortality rate was as high as 10%. After leaving 90% of the Jaguaribeans feeble and impoverished, the gambiae continued their flight. If the mosquitoes should reach "the well-watered Parnahyba and Sâo Francisco River Valleys [in east-central Brazil]," wrote Mr. Fosdick, ". . . it would be impossible to prevent [their] spread to a large part of South. Central, and perhaps even North America. The Parnahyba Valley is 500 miles from Natal; the gambiae mosquitoes are already nearly half way there."

The Foundation has set aside $100.000 for gambiae control in Brazil, and Foundation workers have already learned all the habits of the enemy. Gambiae are "domesticated insects." They breed prolifically, mature within eight days, frequent stagnant, sunlit puddles, prefer to nip their human victims indoors. In the infested parts of Brazil an anti-gambiae corps backed by the Rockefeller Foundation is being rushed into action.