Antimalarial drug use in general populations of tropical Africa.
BACKGROUND
The burden of Plasmodium falciparum malaria has worsened because of the emergence of chloroquine resistance. Antimalarial drug use and drug pressure are critical factors contributing to the selection and spread of resistance. The present study explores the geographical, socio-economic and behavioural factors associated with the use of antimalarial drugs in Africa.


METHODS
The presence of chloroquine (CQ), pyrimethamine (PYR) and other antimalarial drugs has been evaluated by immuno-capture and high-performance liquid chromatography in the urine samples of 3,052 children (2-9 y), randomly drawn in 2003 from the general populations at 30 sites in Senegal (10), Burkina-Faso (10) and Cameroon (10). Questionnaires have been administered to the parents of sampled children and to a random sample of households in each site. The presence of CQ in urine was analysed as dependent variable according to individual and site characteristics using a random - effect logistic regression model to take into account the interdependency of observations made within the same site.


RESULTS
According to the sites, the prevalence rates of CQ and PYR ranged from 9% to 91% and from 0% to 21%, respectively. In multivariate analysis, the presence of CQ in urine was significantly associated with a history of fever during the three days preceding urine sampling (OR = 1.22, p = 0.043), socio-economic level of the population of the sites (OR = 2.74, p = 0.029), age (2-5 y = reference level; 6-9 y OR = 0.76, p = 0.002), prevalence of anti-circumsporozoite protein (CSP) antibodies (low prevalence: reference level; intermediate level OR = 2.47, p = 0.023), proportion of inhabitants who lived in another site one year before (OR = 2.53, p = 0.003), and duration to reach the nearest tarmacked road (duration less than one hour = reference level, duration equal to or more than one hour OR = 0.49, p = 0.019).


CONCLUSIONS
Antimalarial drug pressure varied considerably from one site to another. It was significantly higher in areas with intermediate malaria transmission level and in the most accessible sites. Thus, P. falciparum strains arriving in cross-road sites or in areas with intermediate malaria transmission are exposed to higher drug pressure, which could favour the selection and the spread of drug resistance.
Gardella
Florence
F
Unité de Recherche en Biologie et Epidémiologie Parasitaires (URBEP), IMTSSA, Parc du Pharo - B,P, 46, 13998, Marseille-Armées, France. gardella_f@yahoo.fr
Assi
Serge
S
Simon
Fabrice
F
Bogreau
Hervé
H
Eggelte
Teunis
T
Ba
Fatou
F
Foumane
Vincent
V
Henry
Marie-Claire
MC
Kientega
Pélagie Traore
PT
Basco
Léonardo
L
Trape
Jean-François
JF
Lalou
Richard
R
Martelloni
Maryse
M
Desbordes
Marc
M
Baragatti
Meïli
M
Briolant
Sébastien
S
Almeras
Lionel
L
Pradines
Bruno
B
Fusai
Thierry
T
Rogier
Christophe
C
D000367:Age Factors; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000962:Antimalarials / Q000627:therapeutic use*; D002050:Burkina Faso; D002163:Cameroon; D002648:Child; D002675:Child, Preschool; D002738:Chloroquine / Q000627:therapeutic use*; D002851:Chromatography, High Pressure Liquid; D004351:Drug Resistance; D005260:Female; D005335:Fever of Unknown Origin / Q000188:drug therapy; D005843:Geography; D006801:Humans; D008297:Male; D011739:Pyrimethamine / Q000627:therapeutic use*; D012641:Selection, Genetic; D012675:Senegal; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D014556:Urine / Q000737:chemistry
D000913:Antibodies, Protozoan; D000962:Antimalarials; D002738:Chloroquine; D011739:Pyrimethamine