Impact of preseason treatment on incidence of falciparum malaria and parasite density at a site for testing malaria vaccines in Bandiagara, Mali.
Treating malaria before immunizing has been standard in malaria vaccine field trials. To assess the impact of this practice on subsequent infection and disease incidence, we conducted a randomized cohort study in Bandiagara, Mali. Subjects received a treatment dose of sulfadoxine-pyrimethamine (SP) or no treatment at the beginning of the transmission season. Cumulative and age-specific incidence of clinical episodes was similar between the 2 groups, but SP treatment delayed the median time to first clinical episode from 38.5 to 68 days, and after this initial period of protection, disease incidence in the SP group quickly surpassed the incidence in the untreated group. Parasite densities during disease episodes were lower in the SP group. SP was chosen as the drug for initial parasite clearance for the following reasons: 1) it has been used in previous vaccine trials; 2) our studies have found it to have >99% efficacy in treating uncomplicated malaria in Mali compared to 85-90% efficacy for chloroquine in this area; 3) SP is the approved second-line antimalarial agent in Mali; and 4) its single-dose regimen ensures compliance when treatment is directly observed.
Coulibaly
Drissa
D
Malaria Research and Training Center, Faculty of Medicine, Pharmacy and Dentistry, University of Mali, Bamako, Mali, West Africa.
Diallo
Dapa A
DA
Thera
Mahamadou A
MA
Dicko
Alassane
A
Guindo
Ando B
AB
Koné
Abdoulaye K
AK
Cissoko
Yacouba
Y
Coulibaly
Seydou
S
Djimdé
Abdoulaye
A
Lyke
Kirsten
K
Doumbo
Ogobara K
OK
Plowe
Christopher V
CV
D000293:Adolescent; D000328:Adult; D000818:Animals; D000962:Antimalarials / Q000627:therapeutic use*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D004338:Drug Combinations; D006801:Humans; D015994:Incidence; D007223:Infant; D017780:Malaria Vaccines; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000453:epidemiology*; D008302:Mali; D010963:Plasmodium falciparum / Q000254:growth & development* / Q000302:isolation & purification; D011739:Pyrimethamine / Q000627:therapeutic use*; D012107:Research Design; D012621:Seasons; D013413:Sulfadoxine / Q000627:therapeutic use*; D016896:Treatment Outcome
D000962:Antimalarials; D004338:Drug Combinations; D017780:Malaria Vaccines; C001205:fanasil, pyrimethamine drug combination; D013413:Sulfadoxine; D011739:Pyrimethamine