Acedapsone in the prevention of leprosy: field trial in three high prevalence villages in Micronesia.

The 1,659 non-leprous people in a Micronesian population experiencing an annual leprosy incidence rate of about 7/1,000 were offered 15 acedapsone (DADDS) injections during 1967--1970 for leprosy prevention purposes. Subsequent annual surveillance showed an initial cessation of new cases during the 3-year DADDS campaign, followed by a resumption of cases thereafter at a yearly level of about 2/1,000 with a longer pause and slower rise among those who received the full regimen. A secondary wave of cases that has occurred since 1973 among children born after 1968 shows that post-campaign transmission occurred, probably principally from relapsing multibacillary cases with onset before the campaign. Recommendations are made for a balanced, long-term control program with DADDS preventive treatment limited to contacts of multibacillary cases.