title: Detecting Foci of Malaria Transmission with School Surveys: A Pilot Study in the Gambia.
abstract: In areas of declining malaria transmission such as in The Gambia, the identification of malaria infected individuals becomes increasingly harder. School surveys may be used to identify foci of malaria transmission in the community.
  
  
  
  The survey was carried out in May-June 2011, before the beginning of the malaria transmission season. Thirty two schools in the Upper River Region of The Gambia were selected with probability proportional to size; in each school approximately 100 children were randomly chosen for inclusion in the study. Each child had a finger prick blood sample collected for the determination of antimalarial antibodies by ELISA, malaria infection by microscopy and PCR, and for haemoglobin measurement. In addition, a simple questionnaire on socio-demographic variables and the use of insecticide-treated bed nets was completed. The cut-off for positivity for antimalarial antibodies was obtained using finite mixture models. The clustered nature of the data was taken into account in the analyses.
  
  
  
  A total of 3,277 children were included in the survey. The mean age was 10 years (SD = 2.7) [range 4-21], with males and females evenly distributed. The prevalence of malaria infection as determined by PCR was 13.6% (426/3124) [95% CI = 12.2-16.3] with marked variation between schools (range 3-25%, p<0.001), while the seroprevalence was 7.8% (234/2994) [95%CI = 6.4-9.8] for MSP119, 11.6% (364/2997) [95%CI = 9.4-14.5] for MSP2, and 20.0% (593/2973) [95% CI = 16.5-23.2) for AMA1. The prevalence of all the three antimalarial antibodies positive was 2.7% (79/2920).
  
  
  
  This survey shows that malaria prevalence and seroprevalence before the transmission season were highly heterogeneous.
authors.affiliation: Medical Research Council Unit, Fajara, The Gambia.
authors.forename: Ebako N
authors.initials: EN
authors.lastname: Takem
authors.forename: Muna
authors.initials: M
authors.lastname: Affara
authors.forename: Alfred
authors.initials: A
authors.lastname: Amambua-Ngwa
authors.forename: Joseph
authors.initials: J
authors.lastname: Okebe
authors.forename: Serign J
authors.initials: SJ
authors.lastname: Ceesay
authors.forename: Musa
authors.initials: M
authors.lastname: Jawara
authors.forename: Eniyou
authors.initials: E
authors.lastname: Oriero
authors.forename: Davis
authors.initials: D
authors.lastname: Nwakanma
authors.forename: Margaret
authors.initials: M
authors.lastname: Pinder
authors.forename: Caitlin
authors.initials: C
authors.lastname: Clifford
authors.forename: Makie
authors.initials: M
authors.lastname: Taal
authors.forename: Momodou
authors.initials: M
authors.lastname: Sowe
authors.forename: Penda
authors.initials: P
authors.lastname: Suso
authors.forename: Alphonse
authors.initials: A
authors.lastname: Mendy
authors.forename: Amicoleh
authors.initials: A
authors.lastname: Mbaye
authors.forename: Chris
authors.initials: C
authors.lastname: Drakeley
authors.forename: Umberto
authors.initials: U
authors.lastname: D'Alessandro
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000913:Antibodies, Protozoan / Q000097:blood; D002648:Child; D002675:Child, Preschool; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005714:Gambia / Q000453:epidemiology; D006801:Humans; D057148:Insecticide-Treated Bednets; D008288:Malaria / Q000097:blood / Q000453:epidemiology* / Q000517:prevention & control / Q000635:transmission*; D008297:Male; D010865:Pilot Projects; D016133:Polymerase Chain Reaction; D015995:Prevalence; D012574:Schools; D016036:Seroepidemiologic Studies; D011795:Surveys and Questionnaires; D055815:Young Adult
chemical_list: D000913:Antibodies, Protozoan