title: Modes of hole formation in long-lasting insecticidal nets (LLINs) retrieved from South Eastern Ghana.
abstract: BACKGROUND
  Long-lasting insecticidal nets (LLINs) are expected to provide biological efficacy for at least three years in the field and be sufficiently durable to maintain physical protection. Unfortunately, LLINs structurally deteriorate during use accumulating holes. Hitherto, definitive identification of the causes of hole formation has been difficult based upon qualitative surveys.
  
  
  METHODS
  In this preliminary study, optical and scanning electron microscopy of damage in used polyester (PET) and polyethylene (PE) LLINs randomly collected via a household survey from South Eastern Ghana (n =100) were utilised to identify the cause of individual holes.
  
  
  RESULTS
  Multiple damage mechanisms were identified. In both PET and PE LLINs, the majority of holes were initiated by filament fracture (ductile failure and cutting) and thermal damage.
  
  
  CONCLUSIONS
  No strong correlation was found between the bursting strength of retrieved LLINs and overall hole frequency in either the PET or PE nets suggesting that bursting strength is an unreliable predictor of resistance to hole formation if used as a sole parameter.
authors.affiliation: Friedrich-Maag-Str. 18, 72458, Albstadt, Germany. sabineKkaese@gmail.com.
authors.forename: Sabine K
authors.initials: SK
authors.lastname: Käse
authors.affiliation: Nonwovens Innovation & Research Institute Ltd, Centre for Technical Textiles, School of Design, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT, West Yorkshire, UK. stephenr@nonwovens-innovation.com.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Russell
mesh_terms: D019544:Equipment Failure Analysis; D005869:Ghana; D057148:Insecticide-Treated Bednets; D008855:Microscopy, Electron, Scanning; D011091:Polyesters; D020959:Polyethylene; D013997:Time Factors
chemical_list: D011091:Polyesters; D020959:Polyethylene