Medicine: Doctor to the World

In Geneva last week, the United Nations' World Health Organization wound up its 15th annual assembly on a note of triumph: WHO teams are well on the way to eliminating yaws as a tropical scourge; they have made dramatic progress toward the eradication of malaria. But to a man, the 300 delegates were sobered by the realization that their problems are still bigger than their successes.

Modern technology has obliterated the frontiers of disease. Thanks to jet planes, a louse brushed from the sleeve of a beggar in an Oriental bazaar may attach itself to a tourist who will land in San...