[1] UNDP, WORLD BANK, WHO SPECIAL PROGRAMME RES TRAINING TROP DIS, CH-1211 GENEVA 27, SWITZERLAND
[2] CHO QUAN HOSP, CTR TROP DIS, WELLCOME TRUST CLIN RES UNIT, Ho Chi Minh City, VIETNAM
[3] WELLCOME MAHIDOL UNIV, OXFORD TROP MED RES PROGRAMME, FAC TROP MED, BANGKOK 10400, THAILAND