Despite steady progress since the year 2000 in reducing the overall spread of tuberculosis around the globe, TB still sickens nearly nine million men, women and children each year, killing at least 1.4 million, mostly in the poorer parts of the world. There is also worrisome evidence that some TB strains may be evolving into an even more dangerous cause of human suffering than most people, including many doctors, realize. Sally Lehrman marshaled the relevant data in her July Scientific American feature article "The Diabolical Genius of an Ancient Scourge."

Unless more is done to stop this unexpected chain of events, Lehrman wrote, " TB rates could one day begin rising again globally, and the disease could become harder to treat and spread more widely among populations that have so far been relatively free of the scourge."

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