Search results for "Anopheles gambiae"
showing 10 items of 11 documents
The Population Genomics of Anopheles gambiae Species Complex: Progress and Prospects
2021
Anopheles gambiae sensu lato is a species complex containing principal malaria vectors such as An. gambiae sensu stricto, An. coluzzii, and An. arabiensis. Numerous studies have shown dynamic species hybridization among member of this complex makes them an ideal model for studying evolution and speciation as well as for applied vector biology. Applying a population genomics approach to the An. gambiae and An. coluzzii species group has led to a number of important and epidemiologically relevant insights including: (1) organization of genomic divergence into “islands of speciation”; (2) competing models of population origin of An. gambiae and An. Coluzzii; (3) description of asymmetric intro…
Risk estimation for air travel-induced malaria transmission in central Europe – A mathematical modelling study
2019
Abstract Background Aim of our study was to identify conditions under which malaria transmission caused by imported infectious mosquitoes or travellers could occur at large central European airports, and if such transmission could be sustained by indigenous mosquitoes. Methods We developed a deterministic and a stochastic compartmental Susceptible-Exposed-Infectious-Recovered-Susceptible (humans)/Susceptible-Exposed-Infectious (mosquitoes) model with two mosquito (imported Anopheles gambiae, indigenous A. plumbeus) and three human (travellers, airport personnel exposed/not exposed to imported A. gambiae) populations. We assessed various scenarios to identify combinations of model parameters…
Vertical transmission of naturally occurring Bunyamwera and insect-specific flavivirus infections in mosquitoes from islands and mainland shores of L…
2018
Background Many arboviruses transmitted by mosquitoes have been implicated as causative agents of both human and animal illnesses in East Africa. Although epidemics of arboviral emerging infectious diseases have risen in frequency in recent years, the extent to which mosquitoes maintain pathogens in circulation during inter-epidemic periods is still poorly understood. This study aimed to investigate whether arboviruses may be maintained by vertical transmission via immature life stages of different mosquito vector species. Methodology We collected immature mosquitoes (egg, larva, pupa) on the shores and islands of Lake Baringo and Lake Victoria in western Kenya and reared them to adults. Mo…
Efficacy of an insecticide paint against malaria vectors and nuisance in West Africa--part 2: field evaluation.
2010
Abstract Background Widespread resistance of the main malaria vector Anopheles gambiae to pyrethroids reported in many African countries and operational drawbacks to current IRS methods suggest the convenience of exploring new products and approaches for vector control. Insecticide paint Inesfly 5A IGR™, containing two organophosphates (OPs), chlorpyrifos and diazinon, and one insect growth regulator (IGR), pyriproxyfen, was tested in Benin, West Africa, for 12 months. Methods Field trials were conducted in six experimental huts that were randomly allocated to one or two layers of insecticide at 1 Kg/6 m2 or control. Evaluations included: (i) early mosquito collection, (ii) mosquito release…
Efficacy of an insecticide paint against insecticide-susceptible and resistant mosquitoes - Part 1: Laboratory evaluation
2010
Abstract Background The main malaria vector Anopheles gambiae and the urban pest nuisance Culex quinquefasciatus are increasingly resistant to pyrethroids in many African countries. There is a need for new products and strategies. Insecticide paint Inesfly 5A IGR™, containing two organophosphates (OPs), chlorpyrifos and diazinon, and insect growth regulator (IGR), pyriproxyfen, was tested under laboratory conditions for 12 months following WHOPES Phase I procedures. Methods Mosquitoes used were laboratory strains of Cx. quinquefasciatus susceptible and resistant to OPs. The paint was applied at two different doses (1 kg/6 m2 and 1 kg/12 m2) on different commonly used surfaces: porous (cemen…
Characterization of two globin genes from the malaria mosquito Anopheles gambiae: Divergent origin of nematoceran haemoglobins
2007
The chironomid midges are the only insects that harbour true haemoglobin in their haemolymph. Here we report the identification of haemoglobin genes in two other nematoceran species. Two paralogous haemoglobin genes (glob1 and glob2) from the malaria mosquito Anopheles gambiae were cloned and sequenced. Furthermore, we identified two orthologous haemoglobin genes in the yellow fever mosquito Aedes aegypti. All four haemoglobins were predicted to be intracellular proteins, with the amino acids required for heme- and oxygen-binding being conserved. In situ-hybridization studies showed that glob1 and glob2 expression in An. gambiae is mainly associated with the tracheal system. This pattern re…
Identification and characterisation of the dopamine receptor II from the cat flea Ctenocephalides felis (CfDopRII)
2006
International audience; G protein-coupled receptors (GPCRs) represent a protein family with a wide range of functions. Approximately 30% of human drug targets are GPCRs, illustrating their pharmaceutical relevance. In contrast, the knowledge about invertebrate GPCRs is limited and is mainly restricted to model organisms like Drosophila melanogaster and Caenorhabditis elegans. Especially in ectoparasites like ticks and fleas, only few GPCRs are characterised. From the cat flea Ctenocephalides felis, a relevant parasite of cats and dogs, no GPCRs are known so far. Thus, we performed a bioinformatic analysis of available insect GPCR sequences from the honeybee Apis mellifera, the mosquito Anop…
Targeted application of an organophosphate-based paint applied on windows and doors against Anopheles coluzzii resistant to pyrethroids under real li…
2017
Abstract Background A novel strategy applying an organophosphate-based insecticide paint on doors and windows in combination with long-lasting insecticide-treated nets (LLINs) was tested for the control of pyrethroid-resistant malaria vectors in a village setting in Vallée du Kou, a rice-growing area west of Burkina Faso. Methods Insecticide Paint Inesfly 5A IGR™, comprised of two organophosphates and an insect growth regulator, was applied to doors and windows and tested in combination with pyrethroid-treated LLINs. The killing effect was monitored for 5 months by early morning collections of anophelines and other culicids. The residual efficacy was evaluated monthly by WHO bioassays using…
Evaluation of the efficacy of a new insecticide paint against malaria vectors
2015
La malaria continúa siendo un problema de salud pública global. Se calcula que en el mundo hay 3.300 millones de personas en 97 países y territorios que corren el riesgo de padecer el paludismo, y que para 1.200 millones ese riesgo es elevado (WHO, 2014). El control de la malaria a gran escala está altamente basado en al control del vector, principalmente mediante el uso de mosquiteras tratadas con insecticidas de larga duración (LLINs), y en menor medida, el Rociamiento Residual Intradomiciliario. Todos los tratamientos recomendados de LLINs y la mayoría del Rociamiento Residual Intradomiciliario se basan en el uso de piretroides. La creciente resistencia de los vectores de malaria a los p…
Chemical parameters and bacterial communities associated with larval habitats of Anopheles, Culex and Aedes mosquitoes (Diptera: Culicidae) in wester…
2016
AbstractAquatic larval habitat conditions influence the development, fitness and vectorial capacity of mosquitoes. In turn, human activities can influence these conditions and shape mosquito vector distribution, thus affecting pathogen circulation and transmission. We measured environmental factors (chemical and microbial) in mosquito larval habitats and evaluated their potential as predictors for the occurrence of different mosquito species in an arbovirus and malaria endemic region of western Kenya. We found significantly greater proportions ofAedes aegyptimosquito larvae in ammonium and phosphate rich habitats, suggesting that fertilizer usage could potentially increase aquatic habitat s…