title: Using a near-infrared spectrometer to estimate the age of anopheles mosquitoes exposed to pyrethroids.
abstract: We report on the accuracy of using near-infrared spectroscopy (NIRS) to predict the age of Anopheles mosquitoes reared from wild larvae and a mixed age-wild adult population collected from pit traps after exposure to pyrethroids. The mosquitoes reared from wild larvae were estimated as <7 or ≥7 d old with an overall accuracy of 79%. The age categories of Anopheles mosquitoes that were not exposed to the insecticide papers were predicted with 78% accuracy whereas the age categories of resistant, susceptible and mosquitoes exposed to control papers were predicted with 82%, 78% and 79% accuracy, respectively. The ages of 85% of the wild-collected mixed-age Anopheles were predicted by NIRS as ≤8 d for both susceptible and resistant groups. The age structure of wild-collected mosquitoes was not significantly different for the pyrethroid-susceptible and pyrethroid-resistant mosquitoes (P = 0.210). Based on these findings, NIRS chronological age estimation technique for Anopheles mosquitoes may be independent of insecticide exposure and the environmental conditions to which the mosquitoes are exposed.
authors.affiliation: Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia; Environmental Futures Centre, Griffith University, Brisbane, Queensland, Australia; Environmental Health and Ecological Sciences Thematic Group, Ifakara Health Institute, Ifakara, United Republic of Tanzania.
authors.forename: Maggy T
authors.initials: MT
authors.lastname: Sikulu
authors.affiliation: Vector Group, Liverpool School of Tropical Medicine, Liverpool, United Kingdom; Zanzibar Malaria Control Programme, Ministry of Health and Social Welfare, Zanzibar, United Republic of Tanzania.
authors.forename: Silas
authors.initials: S
authors.lastname: Majambere
authors.affiliation: Zanzibar Malaria Control Programme, Ministry of Health and Social Welfare, Zanzibar, United Republic of Tanzania.
authors.forename: Bakar O
authors.initials: BO
authors.lastname: Khatib
authors.affiliation: Zanzibar Malaria Control Programme, Ministry of Health and Social Welfare, Zanzibar, United Republic of Tanzania.
authors.forename: Abdullah S
authors.initials: AS
authors.lastname: Ali
authors.affiliation: Mosquito Control Laboratory, QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia.
authors.forename: Leon E
authors.initials: LE
authors.lastname: Hugo
authors.affiliation: Engineering and Wind Erosion Research Unit, United States Department of Agriculture/Agricultural Research Services, Center for Grain and Animal Health Research, Manhattan, Kansas, United States of America.
authors.forename: Floyd E
authors.initials: FE
authors.lastname: Dowell
mesh_terms: D000375:Aging; D000818:Animals; D000852:Anopheles / Q000737:chemistry / Q000187:drug effects* / Q000502:physiology; D005260:Female; D007305:Insecticide Resistance; D007306:Insecticides / Q000378:metabolism*; D011722:Pyrethrins / Q000378:metabolism*; D019265:Spectroscopy, Near-Infrared / Q000379:methods
chemical_list: D007306:Insecticides; D011722:Pyrethrins