Phase II: Feasibility assessment of a novel tool for mosquito vector control: Auto-Dissemination Augmented by Males (ADAM)

Project summary abstractMosquito control remains the primary tool for combating many mosquito vectored diseasessuch as DengueChikungunyaZikaand West Nilebecause no approved vaccinetherapeutant or prophylaxis is currently available for useKey deficiencies of existing vector control methods include resistance to existing insecticides and the inability to find and treat cryptic breeding siteswhich provide refuge to immature mosquitoes and allow for the rapid recovery of mosquito populations following conventional control effortsThe self delivering method known as `auto disseminationaddresses this deficiency by using mosquitoes as the vehicle to deliver a potent mosquito growth regulator to cryptic breeding sitesThe Phaseresults have included pilot laboratory and field workas a proof of principle against both Aedes aegypti and Aedes albopictusThe epidemiology of Zika has led to an urgent need for preemptive vector control approachesSpecificallya majority of Zika virus infections in humans are not detected quicklyDelayed detection can undermine a public health protection plan that is based on reactive approachesi ea strategy of initiating intensive vector control only after the detection of an epidemicbecause by the time of detectiona large proportion of the human population can be infected alreadyThe approach being developed in the proposed work is ideal as a preemptive approachbecauseit requires small amounts of chemicali eless environmental impact andthe artificially reared mosquito carriers can be delivered at any timee gbefore an indigenous vector population reaches dangerous levelsTheAuto Dissemination Augmented by MalesADAMis based on mass producing male mosquitoeswhich do not bite or transmit pathogensThe ADAM method can utilize wild type mosquitoesWolbachiainfected mosquitoes or Genetically Modified mosquitoesIntegration with existing mosquito mass rearing programs can speed the uptake of the ADAM technologyAdult ADAM males are treated with an Insect Growth RegulatorIGRand then released to deliver lethal doses of the IGR to oviposition sitesPhase I work includedlaboratory developmentregulatory worke gapproval of a Research Authorization from the California Department of Pesticide Regulationfield trials in KY against Aealbopictusandfield trials in collaboration with the Consolidated Mosquito Abatement DistrictCMADto test the ADAM approach against AeaegyptiThe laboratory results show that AealbopictusAeaegyptiand Culex pipiens males cantolerate the IGR with negligible cost to the male carriersdirectly deliver larvicide to breeding sitesandcross contaminate females with IGR doses that are subsequently lethal to larvaeField trials with both Aeaegypti and Aealbopictus show the ADAM method to cause significant larval mortality and significant reductions in the adult populationwhen compared to the non treated sitesPhasework also included an improvement of methods for the mass manufacturing of adult male mosquitoesIn the proposed Phase II workwe will conduct work to replicate and expand field trials against Aeaegypti and Aealbopictusfrom proof of principle trials to a scale that is adequate for operational use by mosquito abatement districtsBy performing field trials with multiple abatement districts from different statesour proposed Phase II work will satisfy an EPA requirement for commercial registrationi ethat efficacy and safety be demonstrated in multiple ecological contextsIn addition to the EPAthe data will be submitted to the World Health OrganizationWHOVector Control Advisory GroupVCAGwhich serves as an advisory body on new forms of vector controlWHO approval is anticipated to increase international uptake of the ADAM technologyAdditional Phase II work will extend Phase I work with Cxpipiensan important vector of West Nile VirusSpecificallyone or more field trials will provide efficacy data for use against this additionalimportant mosquito specieswhich is another focus of abatement districtsvector control efforts