title: Entomological efficacy of durable wall lining with reduced wall surface coverage for strengthening visceral leishmaniasis vector control in Bangladesh, India and Nepal.
abstract: BACKGROUND
  New methods for controlling sand fly are highly desired by the Visceral Leishmaniasis (VL) elimination program of Bangladesh, India and Nepal for its consolidation and maintenance phases. To support the program we investigated safety, efficacy and cost of Durable Wall Lining to control sand fly.
  
  
  METHODS
  This multicentre randomized controlled study in Bangladesh, India and Nepal included randomized two intervention clusters and one control cluster. Each cluster had 50 households except full wall surface coverage (DWL-FWSC) cluster in Nepal which had 46 households. Ten of 50 households were randomly selected for entomological activities ﻿except India where it was 6 households. Interventions were DWL-FWSC and reduced wall surface coverage (DWL-RWSC) with DWL which covers 1.8 m and 1.5 m height from floor respectively. Efficacy was measured by reduction in sand fly density by intervention and sand fly mortality assessment by the WHO cone bioassay test at 1 month after intervention. Trained field research assistants interviewed household heads for socio-demographic information, knowledge and practice about VL, vector control, and for their experience following the intervention. Cost data was collected using cost data collection tool which was designed for this study. Statistical analysis included difference-in-differences estimate, bivariate analysis, Poisson regression model and incremental cost-efficacy ratio calculation.
  
  
  RESULTS
  Mean sand fly density reduction by DWL-FWSC and DWL-RWSC was respectively -4.96 (95 % CI, -4.54, -5.38) and -5.38 (95 % CI, -4.89, -5.88). The sand fly density reduction attributed by both the interventions were statistically significant after adjusting for covariates (IRR = 0.277, p < 0.001 for DWL-RWSC and IRR = 0.371, p < 0.001 for DWL-FWSC). The efficacy of DWL-RWSC and DWL-FWSC on sand fly density reduction was statistically comparable (p = 0.214). The acceptability of both interventions was high. Transient burning sensations, flash on face and itching were most common adverse events and were observed mostly in Indian site. There was no serious adverse event. DWL-RWSC is cost-saving compared to DWL-FWSC. The incremental cost-efficacy ratio was -6.36, where DWL-RWSC dominates DWL-FWSC.
  
  
  CONCLUSIONS
  DWL-RWSC intervention is safe, efficacious, cost-saving and cost-effective in reducing indoor sand fly density. The VL elimination program in the Indian sub-continent may consider DWL-RWSC for sand fly control for its consolidation and maintenance phases.
authors.affiliation: NCSD and Parasitology Laboratory, International Centre For Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Taj Uddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh.
authors.forename: M Mamun
authors.initials: MM
authors.lastname: Huda
authors.affiliation: Rajendra Memorial Research Institute of Medical Sciences, Patna, India.
authors.forename: Vijay
authors.initials: V
authors.lastname: Kumar
authors.affiliation: Entomology laboratory, Department of Microbiology, BP Koirala Institute of Health Sciences, Dharan, Nepal.
authors.forename: Murari Lal
authors.initials: ML
authors.lastname: Das
authors.affiliation: NCSD and Parasitology Laboratory, International Centre For Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Taj Uddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh.
authors.forename: Debashis
authors.initials: D
authors.lastname: Ghosh
authors.affiliation: Entomology laboratory, Department of Microbiology, BP Koirala Institute of Health Sciences, Dharan, Nepal.
authors.forename: Jyoti
authors.initials: J
authors.lastname: Priyanka
authors.affiliation: Rajendra Memorial Research Institute of Medical Sciences, Patna, India.
authors.forename: Pradeep
authors.initials: P
authors.lastname: Das
authors.affiliation: NCSD and Parasitology Laboratory, International Centre For Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Taj Uddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh.
authors.forename: Abdul
authors.initials: A
authors.lastname: Alim
authors.affiliation: Department of Microbiology and Immunology, McGill University, Montreal, Canada.
authors.forename: Greg
authors.initials: G
authors.lastname: Matlashewski
authors.affiliation: UNICEF/UNDP/World Bank/WHO Special Programme for Research and Training in Tropical Diseases (WHO/TDR), Geneva, Switzerland.|Centre for Medicine and Society, University Medical Centre Freiburg, Freiburg, Germany.
authors.forename: Axel
authors.initials: A
authors.lastname: Kroeger
authors.affiliation: Centre for Medicine and Society, University Medical Centre Freiburg, Freiburg, Germany.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Alfonso-Sierra
authors.affiliation: NCSD and Parasitology Laboratory, International Centre For Diarrhoeal Disease Research, Bangladesh (icddr,b), 68 Shaheed Taj Uddin Ahmed Sarani, Mohakhali, Dhaka, 1212, Bangladesh. din63d@icddrb.org.
authors.forename: Dinesh
authors.initials: D
authors.lastname: Mondal
mesh_terms: D000818:Animals; D001459:Bangladesh; D005191:Family Characteristics; D005260:Female; D006801:Humans; D007194:India; D007300:Insect Control / Q000191:economics / Q000295:instrumentation / Q000379:methods*; D007303:Insect Vectors; D007898:Leishmaniasis, Visceral / Q000517:prevention & control* / Q000635:transmission; D009390:Nepal; D011156:Population Density; D011576:Psychodidae
keywords: Bangladesh; Durable wall lining; India; Kala-azar; Nepal; Sand fly; TDR; Vector control; Visceral leishmaniasis