title: Durability associated efficacy of long-lasting insecticidal nets after five years of household use.
abstract: BACKGROUND
  Long-lasting insecticidal nets (LLINs) have been strongly advocated for use to prevent malaria in sub-Saharan Africa and have significantly reduced human-vector contact. PermaNet® 2.0 is among the five LLINs brands which have been given full approval by the WHO Pesticide Evaluation Scheme (WHOPES). The LLINs are expected to protect the malaria endemic communities, but a number of factors within the community can affect their durability and efficacy. This study evaluated the durability, efficacy and retention of PermaNet® 2.0 after five years of use in a Tanzanian community.
  
  
  METHODS
  Two to three day- old non blood-fed female mosquitoes from an insectary susceptible colony (An. gambiae s.s, this colony was established at TPRI from Kisumu, Kenya in 1992) and wild mosquito populations (An. arabiensis and Culex quinquefasciatus) were used in cone bioassay tests to assess the efficacy of mosquito nets.
  
  
  RESULTS
  The knockdown effect was recorded after three minutes of exposure, and mortality was recorded after 24 hours post-exposure. Mortality of An. gambiae s.s from insectary colony was 100% while An. arabiensis and Cx.quinquefasciatus wild populations had reduced mortality. Insecticide content of the new (the bed net of the same brand but never used before) and used PermaNet® 2.0 was determined using High Performance Liquid Chromatography (HPLC).
  
  
  CONCLUSIONS
  The results of this study suggest that, in order to achieve maximum protection against malaria, public health education focusing on bed net use and maintenance should be incorporated into the mass distribution of nets in communities.
authors.affiliation: Tropical Pesticides Research Institute, Division of Livestock and Human Diseases Vector Control, Mosquito Section, Arusha, Tanzania. pat.kweka@gmail.com
authors.forename: Eliningaya J
authors.initials: EJ
authors.lastname: Kweka
authors.forename: Yousif E
authors.initials: YE
authors.lastname: Himeidan
authors.forename: Aneth M
authors.initials: AM
authors.lastname: Mahande
authors.forename: Beda J
authors.initials: BJ
authors.lastname: Mwang'onde
authors.forename: Shandala
authors.initials: S
authors.lastname: Msangi
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Mahande
authors.forename: Humphrey D
authors.initials: HD
authors.lastname: Mazigo
authors.forename: Mramba
authors.initials: M
authors.lastname: Nyindo
mesh_terms: D000818:Animals; D000852:Anopheles / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D003465:Culex / Q000187:drug effects*; D005191:Family Characteristics; D005260:Female; D006801:Humans; D057148:Insecticide-Treated Bednets; D007306:Insecticides / Q000032:analysis / Q000494:pharmacology*; D009032:Mosquito Control / Q000379:methods*; D016019:Survival Analysis; D013636:Tanzania; D013997:Time Factors
chemical_list: D007306:Insecticides