title: Seasonal prevalence of malaria in West Sumba district, Indonesia.
abstract: BACKGROUND
  Accurate information about the burden of malaria infection at the district or provincial level is required both to plan and assess local malaria control efforts. Although many studies of malaria epidemiology, immunology, and drug resistance have been conducted at many sites in Indonesia, there is little published literature describing malaria prevalence at the district, provincial, or national level.
  
  
  METHODS
  Two stage cluster sampling malaria prevalence surveys were conducted in the wet season and dry season across West Sumba, Nusa Tenggara Province, Indonesia.
  
  
  RESULTS
  Eight thousand eight hundred seventy samples were collected from 45 sub-villages in the surveys. The overall prevalence of malaria infection in the West Sumba District was 6.83% (95% CI, 4.40, 9.26) in the wet season and 4.95% (95% CI, 3.01, 6.90) in the dry. In the wet season Plasmodium falciparum accounted for 70% of infections; in the dry season P. falciparum and Plasmodium vivax were present in equal proportion. Malaria prevalence varied substantially across the district; prevalences in individual sub-villages ranged from 0-34%. The greatest malaria prevalence was in children and teenagers; the geometric mean parasitaemia in infected individuals decreased with age. Malaria infection was clearly associated with decreased haemoglobin concentration in children under 10 years of age, but it is not clear whether this association is causal.
  
  
  CONCLUSIONS
  Malaria is hypoendemic to mesoendemic in West Sumba, Indonesia. The age distribution of parasitaemia suggests that transmission has been stable enough to induce some clinical immunity. These prevalence data will aid the design of future malaria control efforts and will serve as a baseline against which the results of current and future control efforts can be assessed.
authors.affiliation: Eijkman Institute for Molecular Biology, Diponegoro 69, Jakarta 10430, Indonesia. din@eijkman.go.id
authors.forename: Din
authors.initials: D
authors.lastname: Syafruddin
authors.lastname: Krisin
authors.forename: Puji
authors.initials: P
authors.lastname: Asih
authors.lastname: Sekartuti
authors.forename: Rita M
authors.initials: RM
authors.lastname: Dewi
authors.forename: Farah
authors.initials: F
authors.lastname: Coutrier
authors.forename: Ismail E
authors.initials: IE
authors.lastname: Rozy
authors.forename: Augustina I
authors.initials: AI
authors.lastname: Susanti
authors.forename: Iqbal R F
authors.initials: IR
authors.lastname: Elyazar
authors.forename: Awalludin
authors.initials: A
authors.lastname: Sutamihardja
authors.forename: Agus
authors.initials: A
authors.lastname: Rahmat
authors.forename: Michael
authors.initials: M
authors.lastname: Kinzer
authors.forename: William O
authors.initials: WO
authors.lastname: Rogers
mesh_terms: D000293:Adolescent; D000328:Adult; D000740:Anemia / Q000453:epidemiology / Q000209:etiology; D002648:Child; D002675:Child, Preschool; D005260:Female; D006454:Hemoglobins / Q000378:metabolism; D006801:Humans; D007214:Indonesia / Q000453:epidemiology; D007223:Infant; D007231:Infant, Newborn; D008288:Malaria / Q000150:complications / Q000453:epidemiology*; D008297:Male; D015995:Prevalence; D012621:Seasons; D055815:Young Adult
chemical_list: D006454:Hemoglobins