Anti-malarial drug use among preschool children in an area of seasonal malaria transmission in Kenya

The aims of this study were to estimate the proportion of asymptomatic Keny an preschool children using anti-malarial drugs, to identify factors associ ated with chloroquine use, and to assess the validity of frequency of febri le episodes and drug use reported by mothers or carers. Of 318 children stu died, 38% (95% confidence interval [CI] = 30-47%]) tested positive for chlo roquine or sulfadoxine. Of chloroquine-positive children, 15% had concentra tions exceeding the estimated minimum therapeutically effective values. Amo ng Chose testing negative for sulfadoxine, chloroquine-positive children we re more frequently parasitemic (odds ratio = 2.6, 95% CI = 1.3-5.2), and ha d lower mean hemoglobin concentrations (6.1 g/L, 95% CI = 2.1-10.1) than ch loroquine-negative children. Mothers over-reported the frequency of malaria or fever episodes as usually defined in medical studies, and underreported anti-malarial drug use. We conclude that anti-malarials are frequently giv en for treatment of malaria or malaria-associated illness, rather than prop hylactically or for symptoms unrelated to malaria. Questionnaire surveys ca nnot replace biochemical markers to obtain information on anti-malarial dru g use.