title: Survey of Bancroftian filariasis infection in humans and Culex mosquitoes in the western Brazilian Amazon region: implications for transmission and control.
abstract: BACKGROUND
  The aim of this work was to identify possible lymphatic filariasis foci in the western Brazilian Amazonian that could be established from the reports of Rachou in the 1950s. The study was conducted in three cities of the western Brazilian Amazon region - Porto Velho and Guajará-Mirim (State of Rondônia) and Humaitá (State of Amazonas).
  
  
  METHODS
  For human infection evaluation thick blood smear stained with Giemsa was used to analyze samples collected from 10pm to 1am. Polymerase chain reaction (PCR) was used to examine mosquito vectors for the presence of Wuchereria bancrofti DNA. Humans were randomly sampled from night schools students and from inhabitants in neighborhoods lacking sanitation. Mosquitoes were collected from residences only.
  
  
  RESULTS
  A total 2,709 night students enrolled in the Program for Education of Young Adults (EJA), and 935 people registered in the residences near the schools were examined, being 641 from Porto Velho, 214 from Guajará-Mirim and 80 from Humaitá. No individual examined was positive for the presence of microfilariae in the blood stream. A total of 7,860 female Culex quinquefasciatus specimens examined were negative by PCR.
  
  
  CONCLUSIONS
  This survey including human and mosquito examinations indicates that the western Amazon region of Brazil is not a focus of Bancroftian filariasis infection or transmission. Therefore, there is no need to be included in the Brazilian lymphatic filariasis control program.
authors.affiliation: Departamento de Medicina, Faculdade São Lucas, Porto Velho, RO, Brasil.
authors.forename: Rodolfo Luís
authors.initials: RL
authors.lastname: Korte
authors.forename: Gilberto
authors.initials: G
authors.lastname: Fontes
authors.forename: Juliana de Souza Almeida Aranha
authors.initials: Jde S
authors.lastname: Camargo
authors.forename: Eliana Maria Maurício da
authors.initials: EM
authors.lastname: Rocha
authors.forename: Edicarlos André Cavalcante de
authors.initials: EA
authors.lastname: Araújo
authors.forename: Marcelo Zagonel de
authors.initials: MZ
authors.lastname: Oliveira
authors.forename: Rafael Vital dos
authors.initials: RV
authors.lastname: Santos
authors.forename: Luís Marcelo Aranha
authors.initials: LM
authors.lastname: Camargo
mesh_terms: D000293:Adolescent; D000818:Animals; D001938:Brazil / Q000453:epidemiology; D009033:Culicidae / Q000469:parasitology*; D018509:DNA, Helminth / Q000032:analysis; D004605:Elephantiasis, Filarial / Q000175:diagnosis / Q000453:epidemiology* / Q000635:transmission; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology*; D016133:Polymerase Chain Reaction; D011159:Population Surveillance; D014958:Wuchereria bancrofti / Q000235:genetics* / Q000302:isolation & purification; D055815:Young Adult
chemical_list: D018509:DNA, Helminth