Malaria Chemoprophylaxis using Proguanil/Dapsone Combinations on the Thai-Cambodian Border

G. Dennis ShanksDepartments of Medicine and Immunology and Biochemistry, Armed Forces Research Institute of Medical Sciences (AFRIMS), Royal Thai Navy Medical Department, Bangkok, Thailand

Search for other papers by G. Dennis Shanks in
Current site
Google Scholar
PubMed
Close
,
Michael D. EdsteinDepartments of Medicine and Immunology and Biochemistry, Armed Forces Research Institute of Medical Sciences (AFRIMS), Royal Thai Navy Medical Department, Bangkok, Thailand

Search for other papers by Michael D. Edstein in
Current site
Google Scholar
PubMed
Close
,
Varakorn SuriyamongkolDepartments of Medicine and Immunology and Biochemistry, Armed Forces Research Institute of Medical Sciences (AFRIMS), Royal Thai Navy Medical Department, Bangkok, Thailand

Search for other papers by Varakorn Suriyamongkol in
Current site
Google Scholar
PubMed
Close
,
Somkid TimsaadDepartments of Medicine and Immunology and Biochemistry, Armed Forces Research Institute of Medical Sciences (AFRIMS), Royal Thai Navy Medical Department, Bangkok, Thailand

Search for other papers by Somkid Timsaad in
Current site
Google Scholar
PubMed
Close
, and
H. Kyle WebsterDepartments of Medicine and Immunology and Biochemistry, Armed Forces Research Institute of Medical Sciences (AFRIMS), Royal Thai Navy Medical Department, Bangkok, Thailand

Search for other papers by H. Kyle Webster in
Current site
Google Scholar
PubMed
Close
Restricted access

The Thai-Cambodian border is a difficult area in which to provide adequate malaria chemoprophylaxis because of multiple drug-resistant Plasmodium falciparum. In 1990–1991, Thai soldiers were randomly selected to receive proguanil (200 mg/day) combined with dapsone (4 mg or 12.5 mg/day) (n = 184) or pyrimethamine/dapsone (12.5 mg and 100 mg/week) (n = 177). Doxycycline (100 mg/day) was given to men with glucose-6-phosphate dehydrogenase deficiency (n = 77). Falciparum malaria attack rates were the same whether proguanil/dapsone (10.3%) or pyrimethamine/dapsone (11.3%) was used. However, proguanil/dapsone was more effective than pyrimethamine/dapsone in preventing vivax malaria (1.6% versus 12.4%). Men receiving doxycycline had falciparum malaria (3.9%) and vivax malaria (1.3%) at low rates. Adjusting the dapsone component from 4 mg to 12.5 mg did not improve the prophylactic effectiveness. Hematologic toxicity was not observed with the proguanil/dapsone combination. We conclude that proguanil/dapsone is not a useful alternative for malaria chemoprophylaxis on the Thai-Cambodian border.

Save