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The End of Leprosy?

WASHINGTON, D.C.--Citing a stunning decline in leprosy cases worldwide, a new report from the World Health Organization (WHO) in Geneva suggests that the disease can be eliminated by 2000. But WHO officials warn that the agency would be able to complete such a drive only if it raises some $60 million.

Sneezing or coughing spreads Mycobacterium leprae, the bacterium responsible for leprosy. As many as half those infected suffer permanent damage to the skin and nerves, resulting in disfiguring scars that can leave victims shunned by society. Leprosy started to decline in its main stomping grounds--Southeast Asia, Africa, and Latin America--after 1982, when WHO began giving out pills that could completely rid lepers of bacteria in 2 years. The three-drug regimen has worked spectacularly: The number of cases worldwide dropped from 5.3 million in 1985 to less than 1 million in 1995 (see table below).

But further reductions won't come so easy, the report warns. Most of the success so far has been in cities and other accessible areas. To eliminate leprosy, WHO must reduce the number of cases below one in 10,000, a rate low enough to prevent the disease's spread. To do that, the drugs must reach all patients in remote locations, where some people are reluctant to ask for treatment. "It's as difficult to take care of the last 5% [of cases] as it is the first 95%," says Tore Godal, director of the Special Programme for Research and Training in Tropical Diseases, which prepared the report for WHO.

Eliminating leprosy will cost about $370 million, the report estimates. WHO can count on $310 million, mainly from donor countries and nonprofit foundations, over the next 3 years for the leprosy effort. But that will leave an estimated $60 million shortfall, Godal says. Some experts are skeptical that WHO will be able to raise those funds and meet its self-imposed deadline, particularly in countries like Myanmar, the Philippines, and Brazil, where the number of cases is holding steady or rising. Says Gerald Walsh, scientific director for the American Leprosy Foundation in Rockville, Maryland, "It's admirable, but it's going to be difficult."