The effect of mass administration of sulfadoxine-pyrimethamine combined with artesunate on malaria incidence: a double-blind, community-randomized, placebo-controlled trial in The Gambia.
A double-blind, community-randomized, placebo-controlled trial was conducted in a rural area of The Gambia between June and December 1999 to test whether a reduction in the infectious reservoir can reduce malaria transmission. Overall 14,017 (85%) individuals living in the study area were treated with either placebo or sulfadoxine-pyrimethamine (SP) combined with a single dose of artesunate (AS). Following the mass drug administration (MDA) 1375 children aged 6 months to 10 years were kept under surveillance for clinical malaria in 18 villages throughout the 1999 malaria transmission season. During a 20-week surveillance period 637 episodes of malaria were detected. The mean incidence rate was 2.5/100 child-weeks in the placebo villages, and 2.3/100 child-weeks in villages that received SP + AS. The mean rate ratio, adjusted for individual and village-level covariates, was 0.91 (95% CI 0.68-1.22, P = 0.49). During the first 2 months of surveillance, the malaria incidence was lower in treated villages. After 2 months the incidence was slightly higher in the MDA group but this was not statistically significant. Overall, no benefit of the MDA could be detected. The reason for the absence of an impact on malaria transmission is probably the very high basic reproductive number of malaria, and the persistence of mature gametocytes, which are not affected by AS treatment.
von Seidlein
Lorenz
L
Medical Research Council Laboratories, Fajara, The Gambia. lseidlein@ivi.int
Walraven
Gijs
G
Milligan
Paul J
PJ
Alexander
Neal
N
Manneh
Fandingding
F
Deen
Jacqueline L
JL
Coleman
Roz
R
Jawara
Musa
M
Lindsay
Steve W
SW
Drakeley
Chris
C
De Martin
Sarah
S
Olliaro
Piero
P
Bennett
Steve
S
Schim van der Loeff
Maarten
M
Okunoye
Kunle
K
Targett
Geoff A
GA
McAdam
Keith P
KP
Doherty
Justin F
JF
Greenwood
Brian M
BM
Pinder
Margaret
M
D000328:Adult; D000740:Anemia / Q000453:epidemiology; D000962:Antimalarials / Q000008:administration & dosage*; D037621:Artemisinins / Q000008:administration & dosage*; D000077332:Artesunate; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D004338:Drug Combinations; D004359:Drug Therapy, Combination; D005714:Gambia; D006801:Humans; D015994:Incidence; D007223:Infant; D007226:Infant Mortality; D007231:Infant, Newborn; D016778:Malaria, Falciparum / Q000188:drug therapy* / Q000401:mortality; D018512:Parasitemia / Q000188:drug therapy / Q000453:epidemiology; D010349:Patient Compliance; D011739:Pyrimethamine / Q000008:administration & dosage*; D012307:Risk Factors; D012423:Rural Health; D012717:Sesquiterpenes / Q000008:administration & dosage*; D013413:Sulfadoxine / Q000008:administration & dosage*; D016896:Treatment Outcome
D000962:Antimalarials; D037621:Artemisinins; D004338:Drug Combinations; D012717:Sesquiterpenes; C001205:fanasil, pyrimethamine drug combination; D000077332:Artesunate; D013413:Sulfadoxine; D011739:Pyrimethamine