Letter: Epidemic disease under control

Sir: In your article about the present outbreak of cases of plague in India and other epidemic diseases ('Bugs from the past that pose threat to the future', 1 October), Liz Hunt claims that 'leprosy will cripple six million people this year'. The total estimated number of leprosy patients (not new patients in a year) in the world is about six million and less than half of these are crippled.

In 1993, 590,933 new patients were detected, a fall of 60,000 from the previous year. Moreover, as most of these new patients are receiving chemotherapy with three drugs (multi- drug therapy or MDT) before nerve damage occurs, they will not become crippled. The WHO Weekly Epidemiological Record (1994; 69: 145-152) states: 'There is already sufficient indirect evidence to indicate that MDT implementation over the past 10 years has prevented the occurrence of hundreds of thousands of deformities.'

Even more important, chemotherapy not only cures patients but also interrupts transmission of the disease so that when the number of new patients falls to zero, the disease will have been eradicated because transmission only takes place between humans, and once eliminated from any country the disease has not returned.

Yours faithfully,

C. L. CRAWFORD

Department of Anatomy,

Charing Cross and Westminster Medical School

London, W6

3 October