title: Larval control of Anopheles (Nyssorhinchus) darlingi using granular formulation of Bacillus sphaericus in abandoned gold-miners excavation pools in the Brazilian Amazon rainforest.
abstract: BACKGROUND
  Use of a Bacillus sphaericus based mosquito larvicide was evaluated as an intervention for malaria vector control at a mining site in Amapá, Brazil. Impacts on larval and adult densities of the primary vector Anopheles darlingi were measured over the course of a 52 week study period.
  
  
  METHODS
  In Calçoene, State of Amapá, gold mining activity occurs in 19 mining sites in gold-miners of Lourenço. Large pools are formed in mining sites and naturally colonized by Anopheles darlingi. During one year, the impact of applications of VectoLex® CG to these larval sources was evaluated. Applications of 20kg/ha were made as needed, based on 10 immature (3rd, 4th instars and pupae) surveillance of health and established thresholds.
  
  
  RESULTS
  One hundred percent initial control was observed 48h after each treatment. The pools received from 2-10 (5.3±1.6) treatments during the year. The average re-treatment interval in productive pools was 9.4±4.3 weeks. During weeks 3-52 of the study, mean density of late stage larvae was 78% and pupae were 93% lower in the treated pools than in untreated pools (p< 0.0001, n=51) while reduction of adult mosquitoes was 53% in comparison to the untreated area during the last five months of the study, which were the rainy season (p<0.001).
  
  
  CONCLUSIONS
  VectoLex® CG reduced immature Anopheles darlingi infestation levels during the entire study period, and reduced adult mosquito populations during the rainy season.
authors.affiliation: Divisão de Zoologia, Instituto de Pesquisas Científicas e Tecnológicas do Estado do Amapá, Macapá, AP, Brasil. allan.galardo@iepa.ap.gov.br
authors.forename: Allan Kardec Ribeiro
authors.initials: AK
authors.lastname: Galardo
authors.forename: Robert
authors.initials: R
authors.lastname: Zimmerman
authors.forename: Clícia Denis
authors.initials: CD
authors.lastname: Galardo
mesh_terms: D000818:Animals; D000852:Anopheles; D001407:Bacillus; D001938:Brazil; D007303:Insect Vectors; D007814:Larva / Q000254:growth & development*; D008906:Mining; D010572:Pest Control, Biological / Q000379:methods*; D011157:Population Dynamics; D011891:Rain; D012621:Seasons; D014197:Trees