title: Malaria hotspots defined by clinical malaria, asymptomatic carriage, PCR and vector numbers in a low transmission area on the Kenyan Coast.
abstract: BACKGROUND
  Targeted malaria control interventions are expected to be cost-effective. Clinical, parasitological and serological markers of malaria transmission have been used to detect malaria transmission hotspots, but few studies have examined the relationship between the different potential markers in low transmission areas. The present study reports on the relationships between clinical, parasitological, serological and entomological markers of malaria transmission in an area of low transmission intensity in Coastal Kenya.
  
  
  METHODS
  Longitudinal data collected from 831 children aged 5-17 months, cross-sectional survey data from 800 older children and adults, and entomological survey data collected in Ganze on the Kenyan Coast were used in the present study. The spatial scan statistic test used to detect malaria transmission hotspots was based on incidence of clinical malaria episodes, prevalence of asymptomatic asexual parasites carriage detected by microscopy and polymerase chain reaction (PCR), seroprevalence of antibodies to two Plasmodium falciparum merozoite antigens (AMA1 and MSP1-19) and densities of Anopheles mosquitoes in CDC light-trap catches.
  
  
  RESULTS
  There was considerable overlapping of hotspots by these different markers, but only weak to moderate correlation between parasitological and serological markers. PCR prevalence and seroprevalence of antibodies to AMA1 or MSP1-19 appeared to be more sensitive markers of hotspots at very low transmission intensity.
  
  
  CONCLUSIONS
  These findings may support the choice of either serology or PCR as markers in the detection of malaria transmission hotspots for targeted interventions.
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya. tigakd@yahoo.fr.
authors.forename: David Tiga
authors.initials: DT
authors.lastname: Kangoye
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Abdisalan
authors.initials: A
authors.lastname: Noor
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Janet
authors.initials: J
authors.lastname: Midega
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Joyce
authors.initials: J
authors.lastname: Mwongeli
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Dora
authors.initials: D
authors.lastname: Mkabili
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Polycarp
authors.initials: P
authors.lastname: Mogeni
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Christine
authors.initials: C
authors.lastname: Kerubo
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Pauline
authors.initials: P
authors.lastname: Akoo
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Joseph
authors.initials: J
authors.lastname: Mwangangi
authors.affiliation: Department of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, UK.
authors.forename: Chris
authors.initials: C
authors.lastname: Drakeley
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.|Nuffield Department of Medicine, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, UK.
authors.forename: Kevin
authors.initials: K
authors.lastname: Marsh
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.|Nuffield Department of Medicine, Centre for Clinical Vaccinology and Tropical Medicine, Churchill Hospital, University of Oxford, Oxford, UK.
authors.forename: Philip
authors.initials: P
authors.lastname: Bejon
authors.affiliation: Kenya Medical Research Institute-Wellcome Trust Research Programme, Centre for Geographic Medicine Research, P.O. Box 230, Kilifi, 80108, Kenya.
authors.forename: Patricia
authors.initials: P
authors.lastname: Njuguna
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D000852:Anopheles / Q000502:physiology*; D058345:Asymptomatic Infections / Q000453:epidemiology*; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007303:Insect Vectors / Q000502:physiology*; D007630:Kenya / Q000453:epidemiology; D008288:Malaria / Q000175:diagnosis / Q000453:epidemiology* / Q000635:transmission; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011156:Population Density; D015995:Prevalence; D016036:Seroepidemiologic Studies; D055815:Young Adult
keywords: Antibodies; Asymptomatic parasitemia; Hotspots; Malaria; Serology; Spatial scan statistic; Targeted intervention; Transmission