Increasing insecticide resistance in Anopheles funestus and Anopheles arabiensis in Malawi, 2011–2015

Malaria Journal

Research

John Chiphwanya¹  John Zoya¹  Doreen Ali¹  Shadreck Mulenga¹  Jessica Oyugi²  John E. Gimnig²  Kim Lindblade²  Rex B. Mbewe³  Anna Kutengule³  Madalitso Luka-Banda³  Themba Mzilahowa³  Don P. Mathanga³  Martin Chiumia³  Veronica T. Uzalili³  Peter Troell⁴  Jennifer Bergeson-Lockwood⁵  Wilfred Dodoli⁶ 

[1] Community Health Services Unit, National Malaria Control Programme, Ministry of Health, Lilongwe, Malawi;Division of Parasitic Diseases and Malaria, Centers for Diseases Control and Prevention, Atlanta, GA, USA;Malaria Alert Centre, Malawi College of Medicine, P/Bag 360, Chichiri, Blantyre 3, Malawi;President’s Malaria Initiative, Centers for Disease Control and Prevention, Lilongwe, Malawi;President’s Malaria Initiative, United States Agency for International Development, Lilongwe, Malawi;WHO Country-office, Lilongwe, Malawi;

关键词: Anopheles funestus;    Anopheles gambiae;    Insecticide resistance;    Pyrethroid resistance;    Malawi;   

DOI  :  10.1186/s12936-016-1610-1

 received in 2016-07-26, accepted in 2016-11-09,  发布年份 2016

来源: Springer

【 摘 要 】

BackgroundSusceptibility of principal Anopheles malaria vectors to common insecticides was monitored over a 5-year period across Malawi to inform and guide the national malaria control programme.MethodsAdult blood-fed Anopheles spp. and larvae were collected from multiple sites in sixteen districts across the country between 2011 and 2015. First generation (F1) progeny aged 2–5 days old were tested for susceptibility, using standard WHO procedures, against pyrethroids (permethrin and deltamethrin), carbamates (bendiocarb and propoxur), organophosphates (malathion and pirimiphos-methyl) and an organochlorine (DDT).ResultsMortality of Anopheles funestus to deltamethrin, permethrin, bendiocarb and propoxur declined significantly over the 5-year (2011–2015) monitoring period. There was wide variation in susceptibility to DDT but it was not associated with time. In contrast, An. funestus exhibited 100% mortality to the organophosphates (malathion and pirimiphos-methyl) at all sites tested. There was reduced mortality of Anopheles arabiensis to deltamethrin over time though this was not statistically significant. However, mortality of An. arabiensis exposed to permethrin declined significantly over time. Anopheles arabiensis exposed to DDT were more likely to be killed if there was high ITN coverage in the mosquito collection area the previous year. There were no other associations between mosquito mortality in a bioassay and ITN coverage or IRS implementation. Mortality of An. funestus from four sites exposed to deltamethrin alone ranged from 2 to 31% and from 41 to 94% when pre-exposed to the synergist piperonyl butoxide followed by deltamethrin. For permethrin alone, mortality ranged from 2 to 13% while mortality ranged from 63 to 100% when pre-exposed to PBO.ConclusionPyrethroid resistance was detected in An. funestus and An. arabiensis populations across Malawi and has worsened over the last 5 years. New insecticides and control strategies are urgently needed to reduce the burden of malaria in Malawi.

【 授权许可】

CC BY   
© The Author(s) 2016