Bioassay evaluation on the efficacy of α-cypermethrin impregnated into long lasting insecticide treated nets using Anopheles stephensi

Asian Pac J Trop Med. 2012 Oct;5(10):785-8. doi: 10.1016/S1995-7645(12)60144-8.

Abstract

Objective: To evaluate the bioefficacy of α-cypermethrin impregnated into long lasting insecticide treated nets (LLITNs-INTERCEPTOR®) against main malaria vector, Anopheles stephensi (An. stephensi).

Methods: The effectiveness of bed net impregnated with α-cypermethrin (INTERCEPTOR®) with washing was evaluated. The washing procedure and bioassay tests were carried out according to the WHO-recommended methods. Malaria vector, An. stephensi was exposed to impregnated bed net for three minutes and then mortality measured after 24 h recovery period. Knockdown was also measured according to the logarithmic times.

Results: Result of cone bioassay method showed that bioefficacy of α-cypermethrin decreased from 100% in unwashed to 15% in 20 washes. KT(50) was measure as one minute in one wash and increased to 40 min in 20 washes.

Discussion: Findings of this study provide guideline for malaria vector control authorities and people using pyrethroid-impregnated bed nets.

Publication types

  • Evaluation Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Anopheles
  • Biological Assay / methods
  • Guidelines as Topic
  • Humans
  • Insecticide-Treated Bednets / standards*
  • Insecticides / pharmacology*
  • Iran / epidemiology
  • Laundering / methods*
  • Malaria / epidemiology
  • Malaria / prevention & control*
  • Mosquito Control / instrumentation
  • Mosquito Control / standards*
  • Pyrethrins / pharmacology*

Substances

  • Insecticides
  • Pyrethrins
  • cypermethrin