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an affordable, quality-assured community-based system for high-resolution entomological surveillance of vector mosquitoes that reflects human malaria infection risk patterns.more sensitive and scalable entomological surveillance tools are required to monitor low levels of transmission that are increasingly common across the tropics, particularly where vector control has been successful. a large-scale larviciding programme in urban dar es salaam, tanzania is supported by a community-based (cb) system for trapping adult mosquito densities to monitor programme performance.201222624853
human exposure to anopheline mosquitoes occurs primarily indoors, even for users of insecticide-treated nets in luangwa valley, south-east zambia.current front line malaria vector control methods such as indoor residual spraying (irs) and long-lasting insecticidal nets (llins), rely upon the preference of many primary vectors to feed and/or rest inside human habitations where they can be targeted with domestically-applied insecticidal products. we studied the human biting behaviour of the malaria vector anopheles funestus giles and the potential malaria vector anopheles quadriannulatus theobald in luangwa valley, south-east zambia.201222647493
malaria transmission after five years of vector control on bioko island, equatorial guinea.malaria is endemic with year-round transmission on bioko island. the bioko island malaria control project (bimcp) started in 2004 with the aim to reduce malaria transmission and to ultimately eliminate malaria. while the project has been successful in reducing overall malaria morbidity and mortality, foci of high malaria transmission still persist on the island. results from the 2009 entomological collections are reported here.201223146423
genome organization, phylogenies, expression patterns, and three-dimensional protein models of two acetylcholinesterase genes from the red flour beetle.since the report of a paralogous acetylcholinesterase (ache, ec3.1.1.7) gene in the greenbug (schizaphis graminum) in 2002, two different ache genes (ace1 and ace2) have been identified in each of at least 27 insect species. however, the gene models of ace1 and ace2, and their molecular properties have not yet been comprehensively analyzed in any insect species. in this study, we sequenced the full-length cdnas, computationally predicted the corresponding three-dimensional protein models, and pr ...201222359679
rickettsia species in african anopheles mosquitoes.there is higher rate of r. felis infection among febrile patients than in healthy people in sub-saharan africa, predominantly in the rainy season. mosquitoes possess a high vectorial capacity and, because of their abundance and aggressiveness, likely play a role in rickettsial epidemiology.201223118963
cysteine peptidases and their inhibitors in tetranychus urticae: a comparative genomic approach.cysteine peptidases in the two-spotted spider mite tetranychus urticae are involved in essential physiological processes, including proteolytic digestion. cystatins and thyropins are inhibitors of cysteine peptidases that modulate their activity, although their function in this species has yet to be investigated. comparative genomic analyses are powerful tools to obtain advanced knowledge into the presence and evolution of both, peptidases and their inhibitors, and could aid to elucidate issues ...201222784002
the anopheles gambiae ce5, a tight- and fast-binding thrombin inhibitor with post-transcriptionally regulated salivary-restricted expression.mosquito saliva carries a large number of factors with anti-hemostatic, anti-inflammatory and immuno-modulatory activities. the ce5 protein was initially identified during an anopheles gambiae salivary gland transcriptome study and later shown to share sequence similarity with anophelin, a thrombin inhibitor from the saliva of the new world mosquito anopheles albimanus. the ce5 gene was found to encode different mrna isoforms coexisting in several tissues of both male and female mosquitoes, a hi ...201222617725
combining next-generation sequencing and microarray technology into a transcriptomics approach for the non-model organism chironomus riparius.whole-transcriptome gene-expression analyses are commonly performed in species that have a sequenced genome and for which microarrays are commercially available. to do such analyses in species with no or limited genome data, i.e. non-model organisms, necessary transcriptomics resources, i.e. an annotated transcriptome and a validated gene-expression microarray, must first be developed. the aim of the present study was to establish an advanced approach for developing transcriptomics resources for ...201223133553
variation in exposure to anopheles gambiae salivary gland peptide (gsg6-p1) across different malaria transmission settings in the western kenya highlands.the existing metrics of malaria transmission are limited in sensitivity under low transmission intensity. robust surveillance systems are needed as interventions to monitor reduced transmission and prevention of rapid reintroduction. serological tools based on antibody responses to parasite and vector antigens are potential tools for transmission measurements. the current study sought to evaluate antibody responses to anopheles gambiae salivary gland peptide (gsg6- p1), as a biomarker of human e ...201222963464
species shifts in the anopheles gambiae complex: do llins successfully control anopheles arabiensis?high coverage of conventional and long-lasting insecticide treated nets (itns and llins) in parts of e africa are associated with reductions in local malaria burdens. shifts in malaria vector species ratio have coincided with the scale-up suggesting that some species are being controlled by itns/llins better than others.201222438864
lysophosphatidylcholine: a novel modulator of trypanosoma cruzi transmission.lysophosphatidylcholine is a bioactive lipid that regulates a large number of cellular processes and is especially present during the deposition and infiltration of inflammatory cells and deposition of atheromatous plaque. such molecule is also present in saliva and feces of the hematophagous organism rhodnius prolixus, a triatominae bug vector of chagas disease. we have recently demonstrated that lpc is a modulator of trypanosoma cruzi transmission. it acts as a powerful chemoattractant for inf ...201222132309
reproductive isolation and local adaptation quantified for a chromosome inversion in a malaria mosquito.chromosome inversions have long been thought to be involved in speciation and local adaptation. we have little quantitative information, however, about the effects that inversion polymorphisms have on reproductive isolation and viability. here we provide the first estimates from any organism for the total amount of reproductive isolation associated with an inversion segregating in natural populations. we sampled chromosomes from 751 mosquitoes of the malaria vector anopheles funestus along a 142 ...201223550747
identification of wolbachia strains in mosquito disease vectors.wolbachia bacteria are common endosymbionts of insects, and some strains are known to protect their hosts against rna viruses and other parasites. this has led to the suggestion that releasing wolbachia-infected mosquitoes could prevent the transmission of arboviruses and other human parasites. we have identified wolbachia in kenyan populations of the yellow fever vector aedes bromeliae and its relative aedes metallicus, and in mansonia uniformis and mansonia africana, which are vectors of lymph ...201223185484
malaria vectors in lake victoria and adjacent habitats in western kenya.the prevalence of malaria among the residents of the lake victoria basin remains high. the environment associated with the lake may maintain a high number of malaria vectors. lake habitats including water hyacinths have been suspected to be the source of vectors. this study investigated whether malaria vectors breed in the lake habitats and adjacent backwater pools. anopheline larvae were collected within the littoral zone of the lake and adjacent pools located along approximately 24.3 km of the ...201222412913
optimized pan-species and speciation duplex real-time pcr assays for plasmodium parasites detection in malaria vectors.an accurate method for detecting malaria parasites in the mosquito's vector remains an essential component in the vector control. the enzyme linked immunosorbent assay specific for circumsporozoite protein (elisa-csp) is the gold standard method for the detection of malaria parasites in the vector even if it presents some limitations. here, we optimized multiplex real-time pcr assays to accurately detect minor populations in mixed infection with multiple plasmodium species in the african malaria ...201223285168
multicentre studies of insecticide-treated durable wall lining in africa and south-east asia: entomological efficacy and household acceptability during one year of field use.indoor residual spraying (irs) is a primary method of malaria vector control, but its potential impact is constrained by several inherent limitations: spraying must be repeated when insecticide residues decay, householders can tire of the annual imposition and campaign costs are recurrent. durable lining (dl) can be considered an advanced form of long-lasting irs where insecticide is gradually released from an aesthetically attractive wall lining material to provide vector control for several ye ...201223107112
the effects of urbanization on global plasmodium vivax malaria transmission.many recent studies have examined the impact of urbanization on plasmodium falciparum malaria endemicity and found a general trend of reduced transmission in urban areas. however, none has examined the effect of urbanization on plasmodium vivax malaria, which is the most widely distributed malaria species and can also cause severe clinical syndromes in humans. in this study, a set of 10,003 community-based p. vivax parasite rate (pvpr) surveys are used to explore the relationships between pvpr i ...201223217010
the effect of bacterial challenge on ferritin regulation in the yellow fever mosquito, aedes aegypti.secreted ferritin is the major iron storage and transport protein in insects. here, we characterize the message and protein expression profiles of yellow fever mosquito (aedes aegypti) ferritin heavy chain homologue (hch) and light chain homologue (lch) subunits in response to iron and bacterial challenge. in vivo experiments demonstrated tissue-specific regulation of hch and lch expression over time post-blood meal (pbm). transcriptional regulation of hch and lch was treatment specific, with di ...201223956079
rapid molecular detection methods for arboviruses of livestock of importance to northern europe.arthropod-borne viruses (arboviruses) have been responsible for some of the most explosive epidemics of emerging infectious diseases over the past decade. their impact on both human and livestock populations has been dramatic. the early detection either through surveillance or diagnosis of virus will be a critical feature in responding and resolving the emergence of such epidemics in the future. although some of the most important emerging arboviruses are human pathogens, this paper aims to high ...201222219660
aging partially restores the efficacy of malaria vector control in insecticide-resistant populations of anopheles gambiae s.l. from burkina faso.abstract: background: the operational impact of insecticide resistance on the effectiveness of long-lasting insecticide nets (llins) and indoor residual spraying (irs) is poorly understood. one factor which may prolong the effectiveness of these tools in the field is the increase in insecticide susceptibility with mosquito age. in this study, llins and irs were tested against young (three to five days) and old (17-19 days) pyrethroid resistant anopheles gambiae s.l. from burkina faso. methods: ...201222269002
Transplacental Transmission of Plasmodium falciparum in a Highly Malaria Endemic Area of Burkina Faso.Malaria congenital infection constitutes a major risk in malaria endemic areas. In this study, we report the prevalence of transplacental malaria in Burkina Faso. In labour and delivery units, thick and thin blood films were made from maternal, placental, and umbilical cord blood to determine malaria infection. A total of 1,309 mother/baby pairs were recruited. Eighteen cord blood samples (1.4%) contained malaria parasites (Plasmodium falciparum). Out of the 369 (28.2%) women with peripheral pos ...201222174725
longitudinal follow-up of malaria transmission dynamics in two villages in a sahelian area of niger during a nationwide insecticide-treated bednet distribution programme.malaria transmission was monitored in two villages in the sahel zone of niger over 4 years. during this period, a nationwide vector control programme was carried out in which insecticide-treated bednets were distributed free to mothers of children aged <5 years. anopheles gambiae and anopheles arabiensis (diptera: culicidae) were found to be the major malaria vectors. the dynamics of an. gambiae s.l. did not vary dramatically over the study period although the proportion of female mosquitoes fou ...201222680979
[agricultural activities and epidemiology of malaria in soudano-sahelian zone in cameroon].we have comparatively studied the dynamics of malaria transmission in the villages of mokolo-douvar located in the rural area with traditional agriculture and gounougou irrigated rice area, in 2004 august and november and 2006 may and october, to assess vectors biting habits, and malaria inoculation rate and malaria parasite prevalence in cohort of children from 0 to 15 years. mosquitoes were collected by landing catches on volunteers and by pyrethrum spray collections. a total of 5961 anopheles ...201222294407
the effect of rainstorms on adult anopheles funestus behavior and survival.we describe the effect that the passage of a cold front, with a subsequent heavy rainstorm ten days later, had on a population of anopheles funestus mosquitoes collected exiting houses or in light-traps from a village in southern mozambique. temperature effects explained 40% (r=0.634; p <0.001) of the variation in numbers of males collected and 19% of the variation in gravid females collected (r=0.437; p=0.033). the age structure of mosquitoes varied according to distance from the breeding site ...201222548561
changes in anopheles funestus biting behavior following universal coverage of long-lasting insecticidal nets in benin.behavioral modification of malaria vectors in response to vector control methods is of great concern. we investigated whether full coverage of long-lasting insecticide-treated mosquito nets (llins) may induce a switch in biting behavior in anopheles funestus, a major malaria vector in africa.201222966127
some like it cool: the effect of ambient temperature on the size of anopheles funestus from southern mozambique.the wing lengths of 3,553 unfed, recently emerged, and 13,256 gravid female anopheles funestus giles from exit collections, undertaken between march 2004 and may 2005, were measured. only in the warmest months were mean wing lengths of unfed females significantly smaller than gravid females. mean wing lengths of unfed, females varied from 2.26 mm (bootstrap 95% ci [2.25-2.27]) in january when mean air temperatures were 24.8 degrees c to 2.70 mm (bootstrap 95% ci [2.68-2.72]) in july when mean te ...201223025198
Multimodal pyrethroid resistance in malaria vectors, Anopheles gambiae s.s., Anopheles arabiensis, and Anopheles funestus s.s. in western Kenya.Anopheles gambiae s.s., Anopheles arabiensis, and Anopheles funestus s.s. are the most important species for malaria transmission. Pyrethroid resistance of these vector mosquitoes is one of the main obstacles against effective vector control. The objective of the present study was to monitor the pyrethroid susceptibility in the 3 major malaria vectors in a highly malaria endemic area in western Kenya and to elucidate the mechanisms of pyrethroid resistance in these species. Gembe East and West, ...201121853038
Lymphatic filariasis in the Democratic Republic of Congo; micro-stratification overlap mapping (MOM) as a prerequisite for control and surveillance.The Democratic Republic of Congo (DRC) has a significant burden of lymphatic filariasis (LF) caused by the parasite Wuchereria bancrofti. A major impediment to the expansion of the LF elimination programme is the risk of serious adverse events (SAEs) associated with the use of ivermectin in areas co-endemic for onchocerciasis and loiasis. It is important to analyse these and other factors, such as soil transmitted helminths (STH) and malaria co-endemicity, which will impact on LF elimination.201121923949
large-scale use of mosquito larval source management for malaria control in africa: a cost analysis.at present, large-scale use of two malaria vector control methods, long-lasting insecticidal nets (llins) and indoor residual spraying (irs) is being scaled up in africa with substantial funding from donors. a third vector control method, larval source management (lsm), has been historically very successful and is today widely used for mosquito control globally, except in africa. with increasing risk of insecticide resistance and a shift to more exophilic vectors, lsm is now under re-evaluation ...201122067606
repellent plants provide affordable natural screening to prevent mosquito house entry in tropical rural settings--results from a pilot efficacy study.sustained malaria control is underway using a combination of vector control, prompt diagnosis and treatment of malaria cases. progress is excellent, but for long-term control, low-cost, sustainable tools that supplement existing control programs are needed. conventional vector control tools such as indoor residual spraying and house screening are highly effective, but difficult to deliver in rural areas. therefore, an additional means of reducing mosquito house entry was evaluated: the screening ...201122022471
chromosomal inversions, natural selection and adaptation in the malaria vector anopheles funestus.chromosomal polymorphisms, such as inversions, are presumably involved in the rapid adaptation of populations to local environmental conditions. reduced recombination between alternative arrangements in heterozygotes may protect sets of locally adapted genes, promoting ecological divergence and potentially leading to reproductive isolation and speciation. through a comparative analysis of chromosomal inversions and microsatellite marker polymorphisms, we hereby present biological evidence that s ...201120837604
Comparative genomics of the anopheline glutathione s-transferase epsilon cluster.Enzymes of the glutathione S-transferase (GST) family play critical roles in detoxification of xenobiotics across many taxa. While GSTs are ubiquitous both in animals and plants, the GST epsilon class (GSTE) is insect-specific and has been associated with resistance to chemical insecticides. While both Aedes aegypti and Anopheles gambiae GSTE clusters consist of eight members, only four putative orthologs are identifiable between the species, suggesting independent expansions of the class in eac ...201122206003
reactive oxygen species-dependent cell signaling regulates the mosquito immune response to plasmodium falciparum.reactive oxygen species (ros) have been implicated in direct killing of pathogens, increased tissue damage, and regulation of immune signaling pathways in mammalian cells. available research suggests that analogous phenomena affect the establishment of plasmodium infection in anopheles mosquitoes. we have previously shown that provision of human insulin in a blood meal leads to increased ros levels in anopheles stephensi. here, we demonstrate that provision of human insulin significantly increas ...201121126166
vectorial status and insecticide resistance of anopheles funestus from a sugar estate in southern mozambique.the dual problems of rising insecticide resistance in the malaria vectors and increasing human malaria cases since 2001 in southern mozambique are cause for serious concern. the selection of insecticides for use in indoor residual spraying (irs) programmes is highly dependent on the extent to which local mosquitoes are susceptible to the approved classes of insecticides. the insecticide resistance status and role in malaria transmission of anopheles funestus was evaluated at the maragra sugar es ...201121306631
chromosomal and environmental determinants of morphometric variation in natural populations of the malaria vector anopheles funestus in cameroon.anopheles funestus is one of the most proficient malaria vectors in the world, mainly because of its remarkable ability to populate a wide range of ecological settings across africa. its formidable environmental plasticity has been primarily associated to high amounts of genetic and inversion polymorphisms. however, very little is known about the morphological changes that this ecological adaptation entails. here, we report on wing morphometric variations in karyotyped specimens of this species ...201121414420
Analysis of Transcriptome Differences between Resistant and Susceptible Strains of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae).The citrus red mite is a worldwide citrus pest and a common sensitizing allergen of asthma and rhinitis. It has developed strong resistance to many registered acaricides, However, the molecular mechanisms of resistance remain unknown. we therefore used next generation sequencing technology to investigate the global transcriptomes between resistant strains and susceptible strains.201122162774
monitoring mosquitoes in urban dar es salaam: evaluation of resting boxes, window exit traps, cdc light traps, ifakara tent traps and human landing catches.ifakara tent traps (itt) are currently the only sufficiently sensitive, safe, affordable and practical method for routine monitoring host-seeking mosquito densities in dar es salaam. however, it is not clear whether itt catches represent indoors or outdoors biting densities. itt do not yield samples of resting, fed mosquitoes for blood meal analysis.201121418622
identification and characterization of a novel chitinase-like gene cluster (agcht5) possibly derived from tandem duplications in the african malaria mosquito, anopheles gambiae.insect chitinase 5 (cht5), a well-characterized enzyme found in the molting fluid and/or integument, is classified as a group i chitinase and is usually encoded by a single gene. in this study, a cht5 gene cluster consisting of five different chitinase-like genes (agcht5-1, agcht5-2, agcht5-3, agcht5-4 and agcht5-5) was identified by a bioinformatics search of the genome of anopheles gambiae. the gene models were confirmed by cloning and sequencing of the corresponding cdnas and gene expression ...201121419847
humoral response to the anopheles gambiae salivary protein gsg6: a serological indicator of exposure to afrotropical malaria vectors.salivary proteins injected by blood feeding arthropods into their hosts evoke a saliva-specific humoral response which can be useful to evaluate exposure to bites of disease vectors. however, saliva of hematophagous arthropods is a complex cocktail of bioactive factors and its use in immunoassays can be misleading because of potential cross-reactivity to other antigens. toward the development of a serological marker of exposure to afrotropical malaria vectors we expressed the anopheles gambiae g ...201121437289
crystal structure of native anopheles gambiae serpin-2, a negative regulator of melanization in mosquitoes. 201121465556
plasmodium falciparum transmission and aridity: a kenyan experience from the dry lands of baringo and its implications for anopheles arabiensis control.abstract: background: the ecology of malaria vectors particularly in semi-arid areas of africa is poorly understood. accurate knowledge on this subject will boost current efforts to reduce the burden of malaria in sub-saharan africa. the objective of this study was to describe the dynamics of malaria transmission in two model semi-arid sites (kamarimar and tirion) in baringo in kenya. methods: adult mosquitoes were collected indoors by pyrethrum spray collections (psc) and outdoors by centers fo ...201121569546
comparative genomic analysis of chitinase and chitinase-like genes in the african malaria mosquito (anopheles gambiae).chitinase is an important enzyme responsible for chitin metabolism in a wide range of organisms including bacteria, yeasts and other fungi, nematodes and arthropods. however, current knowledge on chitinolytic enzymes, especially their structures, functions and regulation is very limited. in this study we have identified 20 chitinase and chitinase-like genes in the african malaria mosquito, anopheles gambiae, through genome-wide searching and transcript profiling. we assigned these genes into eig ...201121611131
mosquito species abundance and diversity in malindi, kenya and their potential implication in pathogen transmission.mosquitoes (diptera: culicidae) are important vectors of human disease-causing pathogens. mosquitoes are found both in rural and urban areas. deteriorating infrastructure, poor access to health, water and sanitation services, increasing population density, and widespread poverty contribute to conditions that modify the environment, which directly influences the risk of disease within the urban and peri-urban ecosystem. the objective of this study was to evaluate the mosquito vector abundance and ...201121626425
why are anopheline mosquitoes not present in the seychelles?species of anopheline mosquitoes are largely distributed over emerged lands around the world and, within the tropics, few areas are without these insects, which are vectors of malaria parasites. among the exceptions is the seychelles archipelago in the western indian ocean. however, in the aldabra island group, located in the extreme western portion of the archipelago, anopheles gambiae s.l. was introduced, leading to massive proliferation and then elimination, with the most recent autochthonous ...201121303530
the contribution of aestivating mosquitoes to the persistence of anopheles gambiae in the sahel.abstract: background: persistence of african anophelines throughout the long dry season (4-8 months) when no surface waters are available remains one of the enduring mysteries of medical entomology. recent studies demonstrated that aestivation (summer diapause) is one mechanism that allows the african malaria mosquito, anopheles gambiae, to persist in the sahel. however, migration from distant localities - where reproduction continues year-round - might also be involved. methods: to assess the c ...201121645385
wide cross-reactivity between anopheles gambiae and anopheles funestus sg6 salivary proteins supports exploitation of gsg6 as a marker of human exposure to major malaria vectors in tropical africa.abstract: background: the anopheles gambiae gsg6 is an anopheline-specific salivary protein which helps female mosquitoes to efficiently feed on blood. besides its role in haematophagy, gsg6 is immunogenic and elicits in exposed individuals an igg response, which may be used as indicator of exposure to the main african malaria vector a. gambiae. however, malaria transmission in tropical africa is sustained by three main vectors (a. gambiae, anopheles arabiensis and anopheles funestus) and a gene ...201121794142
surveillance of vector populations and malaria transmission during the 2009/10 el niño event in the western kenya highlands: opportunities for early detection of malaria hyper-transmission.abstract:201121781291
is the current decline in malaria burden in sub-saharan africa due to a decrease in vector population?abstract: background: in sub-saharan africa (ssa), malaria caused by plasmodium falciparum has historically been a major contributor to morbidity and mortality. recent reports indicate a pronounced decline in infection and disease rates which are commonly ascribed to large-scale bed net programmes and improved case management. however, the decline has also occurred in areas with limited or no intervention. the present study assessed temporal changes in anopheline populations in two highly malari ...201121752273
genome-wide profiling of diel and circadian gene expression in the malaria vector anopheles gambiae.anopheles gambiae, the primary african vector of malaria parasites, exhibits numerous rhythmic behaviors including flight activity, swarming, mating, host seeking, egg laying, and sugar feeding. however, little work has been performed to elucidate the molecular basis for these daily rhythms. to study how gene expression is regulated globally by diel and circadian mechanisms, we have undertaken a dna microarray analysis of an. gambiae under light/dark cycle (ld) and constant dark (dd) conditions. ...201121715657
development of environmental tools for anopheline larval control.malaria mosquitoes spend a considerable part of their life in the aquatic stage, rendering them vulnerable to interventions directed to aquatic habitats. recent successes of mosquito larval control have been reported using environmental and biological tools. here, we report the effects of shading by plants and biological control agents on the development and survival of anopheline and culicine mosquito larvae in man-made natural habitats in western kenya. trials consisted of environmental manipu ...201121733150
efficacy of permanet-« 2.0 and permanet-« 3.0 against insecticide-resistant anopheles gambiae in experimental huts in c+¦te d'ivoire.pyrethroid resistance in vectors could limit the efficacy of long-lasting insecticidal nets (llins) because all llins are currently treated with pyrethroids. the goal of this study was to evaluate the efficacy and wash resistance of permanet-« 3.0 compared to permanet-« 2.0 in an area of high pyrethroid in c+¦te d'ivoire. permanet-« 3.0 is impregnated with deltamethrin at 85 mg/m2 on the sides of the net and with deltamethrin and piperonyl butoxide on the roof. permanet-« 2.0 is impregnated with ...201121699703
the influence of mosquito resting behaviour and associated microclimate for malaria risk.abstract:201121736735
evaluating rnalater-« as a preservative for using near-infrared spectroscopy to predict anopheles gambiae age and species.abstract:201121740582
lethal and pre-lethal effects of a fungal biopesticide contribute to substantial and rapid control of malaria vectors.rapidly emerging insecticide resistance is creating an urgent need for new active ingredients to control the adult mosquitoes that vector malaria. biopesticides based on the spores of entomopathogenic fungi have shown considerable promise by causing very substantial mortality within 7-14 days of exposure. this mortality will generate excellent malaria control if there is a high likelihood that mosquitoes contact fungi early in their adult lives. however, where contact rates are lower, as might r ...201121897846
Dynamics of insecticide resistance in malaria vectors in Benin: first evidence of the presence of L1014S kdr mutation in Anopheles gambiae from West Africa.Insecticide resistance monitoring is essential to help national programmers to implement more effective and sustainable malaria control strategies in endemic countries. This study reported the spatial and seasonal variations of insecticide resistance in malaria vectors in Benin, West Africa.201121910856
Impact of insecticide-treated bed nets on malaria transmission indices on the south coast of Kenya.ABSTRACT: BACKGROUND: Besides significantly reducing malaria vector densities, prolonged usage of bed nets has been linked to decline of Anopheles gambiae s.s. relative to Anopheles arabiensis, changes in host feeding preference of malaria vectors, and behavioural shifts to exophagy (outdoor biting) for the two important malaria vectors in Africa, An. gambiae s.l. and Anopheles funestus. In southern coastal Kenya, bed net use was negligible in 1997-1998 when Anopheles funestus and An. gambiae s ...201122165904
Nigeria anopheles vector database: an overview of 100 years' research.Anopheles mosquitoes are important vectors of malaria and lymphatic filariasis (LF), which are major public health diseases in Nigeria. Malaria is caused by infection with a protozoan parasite of the genus Plasmodium and LF by the parasitic worm Wuchereria bancrofti. Updating our knowledge of the Anopheles species is vital in planning and implementing evidence based vector control programs. To present a comprehensive report on the spatial distribution and composition of these vectors, all publis ...201122162764
requirements for effective malaria control with homing endonuclease genes.malaria continues to impose a substantial burden on human health. we have previously proposed that biological approaches to control the mosquito vector of disease could be developed using homing endonuclease genes (hegs), a class of selfish or parasitic gene that exists naturally in many microbes. recent lab studies have demonstrated that hegs can function in mosquitoes. we constructed and analyzed a model of mosquito population genetics and malaria epidemiology to determine how well hegs need t ...201121976487
evaluating the potential of the sterile insect technique for malaria control: relative fitness and mating compatibility between laboratory colonized and a wild population of anopheles arabiensis from the kruger national park, south africa.the successful suppression of a target insect population using the sterile insect technique (sit) partly depends on the premise that the laboratory insects used for mass rearing are genetically compatible with the target population, that the mating competitiveness of laboratory reared males is at least comparable to that of their wild counterparts, and that mass rearing and sterilization processes do not in themselves compromise male fitness to a degree that precludes them from successfully comp ...201122041133
degradation of insecticides used for indoor spraying in malaria control and possible solutions.the insecticide dichloro-diphenyl-trichloroethane (ddt) is widely used in indoor residual spraying (irs) for malaria control owing to its longer residual efficacy in the field compared to other world health organization (who) alternatives. suitable stabilization to render these alternative insecticides longer lasting could provide a less controversial and more acceptable and effective alternative insecticide formulations than ddt.201122008292
variations of insecticide residual bio-efficacy on different types of walls: results from a community-based trial in south cameroon.determination of residual activity of insecticides is essential information for the selection of appropriate indoor spraying operation. the present study was undertaken to evaluate the residual effect of three candidate insecticide formulations on different indoor surfaces in order to guide future interventions, in the context of cameroon and other african countries.201122047173
insecticide resistance and the future of malaria control in zambia.in line with the global trend to improve malaria control efforts a major campaign of insecticide treated net distribution was initiated in 1999 and indoor residual spraying with ddt or pyrethroids was reintroduced in 2000 in zambia. in 2006, these efforts were strengthened by the president's malaria initiative. this manuscript reports on the monitoring and evaluation of these activities and the potential impact of emerging insecticide resistance on disease transmission.201121915314
exploring mechanisms of multiple insecticide resistance in a population of the malaria vector anopheles funestus in benin.the insecticide resistance status of the malaria vector anopheles funestus and the underlying resistance mechanisms remain uncharacterised in many parts of africa, notably in benin, west africa. to fill this gap in our knowledge, we assessed the susceptibility status of a population of this species in pahou, southern benin and investigated the potential resistance mechanisms.201122110757
methods to collect anopheles mosquitoes and evaluate malaria transmission: a comparative study in two villages in senegal.various methods have been studied as replacement of human landing catches (hlc) for mosquito sampling in entomological studies on malaria transmission. conflicting results have been obtained in comparing relative efficiency of alternative methods, according to the area, the species present and their density. the aim of this study was to compare the number and characteristics of mosquitoes sampled in two areas of senegal by three different methods: hlc, light traps adjacent to an occupied bed net ...201121929747
malaria antifolate resistance with contrasting plasmodium falciparum dihydrofolate reductase (dhfr) polymorphisms in humans and anopheles mosquitoes.surveillance for drug-resistant parasites in human blood is a major effort in malaria control. here we report contrasting antifolate resistance polymorphisms in plasmodium falciparum when parasites in human blood were compared with parasites in anopheles vector mosquitoes from sleeping huts in rural zambia. dna encoding p. falciparum dihydrofolate reductase (ec 1.5.1.3) was amplified by pcr with allele-specific restriction enzyme digestions. markedly prevalent pyrimethamine-resistant mutants wer ...201122065788
Prevalence of Malaria among Patients Attending Public Health Facilities in Maputo City, Mozambique.Abstract. We conducted a health facility-based survey to estimate the prevalence of malaria among febrile patients at health facilities (HFs) in Maputo City. Patients answered a questionnaire on malaria risk factors and underwent malaria testing. A malaria case was defined as a positive result for malaria by microscopy in a patient with fever or history of fever in the previous 24 hours. Among 706 patients with complete information, 111 (15.7%) cases were identified: 105 were positive for Plasmo ...201122144434
insight into the salivary transcriptome and proteome of dipetalogaster maxima.dipetalogaster maxima is a blood-sucking hemiptera that inhabits sylvatic areas in mexico. it usually takes its blood meal from lizards, but following human population growth, it invaded suburban areas, feeding also on humans and domestic animals. hematophagous insect salivary glands produce potent pharmacologic compounds that counteract host hemostasis, including anticlotting, antiplatelet, and vasodilatory molecules. to obtain further insight into the salivary biochemical and pharmacologic com ...201121058630
genetic and phenotypic variation of the malaria vector anopheles atroparvus in southern europe.there is a growing concern that global climate change will affect the potential for pathogen transmission by insect species that are vectors of human diseases. one of these species is the former european malaria vector, anopheles atroparvus. levels of population differentiation of an. atroparvus from southern europe were characterized as a first attempt to elucidate patterns of population structure of this former malaria vector. results are discussed in light of a hypothetical situation of re-es ...201121223582
spatial and temporal variation in the kdr allele l1014s in anopheles gambiae s.s. and phenotypic variability in susceptibility to insecticides in western kenya.malaria vector control in africa depends upon effective insecticides in bed nets and indoor residual sprays. this study investigated the extent of insecticide resistance in anopheles gambiae s.l., anopheles gambiae s.s. and anopheles arabiensis in western kenya where ownership of insecticide-treated bed nets has risen steadily from the late 1990s to 2010. temporal and spatial variation in the frequency of a knock down resistance (kdr) allele in a. gambiae s.s. was quantified, as was variation in ...201121235783
analysis of the evolutionary forces shaping mitochondrial genomes of a neotropical malaria vector complex.many vectors of human malaria belong to complexes of morphologically indistinguishable cryptic species. here we report the analysis of the newly sequenced complete mitochondrial dna molecules from six recognized or putative species of one such group, the neotropical anopheles albitarsis complex. the molecular evolution of these genomes had been driven by purifying selection, particularly strongly acting on the rna genes. directional mutation pressure associated with the strand-asynchronous asymm ...201121241811
chlorfenapyr: a new insecticide with novel mode of action can control pyrethroid resistant malaria vectors.malaria vectors have acquired widespread resistance to many of the currently used insecticides, including synthetic pyrethroids. hence, there is an urgent need to develop alternative insecticides for effective management of insecticide resistance in malaria vectors. in the present study, chlorfenapyr was evaluated against anopheles culicifacies and anopheles stephensi for its possible use in vector control.201121266037
development of a new version of the liverpool malaria model. i. refining the parameter settings and mathematical formulation of basic processes based on a literature review.a warm and humid climate triggers several water-associated diseases such as malaria. climate- or weather-driven malaria models, therefore, allow for a better understanding of malaria transmission dynamics. the liverpool malaria model (lmm) is a mathematical-biological model of malaria parasite dynamics using daily temperature and precipitation data. in this study, the parameter settings of the lmm are refined and a new mathematical formulation of key processes related to the growth and size of t ...201121314922
dry season ecology of anopheles gambiae complex mosquitoes at larval habitats in two traditionally semi-arid villages in baringo, kenya.pre-adult stages of malaria vectors in semi-arid areas are confronted with highly variable and challenging climatic conditions. the objective of this study was to determine which larval habitat types are most productive in terms of larval densities in the dry and wet seasons within semi-arid environments, and how vector species productivity is partitioned over time.201121352608
a de novo expression profiling of anopheles funestus, malaria vector in africa, using 454 pyrosequencing.anopheles funestus is one of the major malaria vectors in africa and yet there are few genomic tools available for this species compared to an. gambiae. to start to close this knowledge gap, we sequenced the an. funestus transcriptome using cdna libraries developed from a pyrethroid resistant laboratory strain and a pyrethroid susceptible field strain from mali.201121364769
increased proportions of outdoor feeding among residual malaria vector populations following increased use of insecticide-treated nets in rural tanzania.abstract:201121477321
a longitudinal study on anopheles mosquito larval abundance in distinct geographical and environmental settings in western kenya.abstract:201121477340
identification and distribution of a gaba receptor mutation conferring dieldrin resistance in the malaria vector anopheles funestus in africa.growing problems of pyrethroid resistance in anopheles funestus have intensified efforts to identify alternative insecticides. many agrochemicals target the gaba receptors, but cross-resistance from dieldrin resistance may preclude their introduction. dieldrin resistance was detected in an. funestus populations from west (burkina faso) and central (cameroon) africa, but populations from east (uganda) and southern africa (mozambique and malawi) were fully susceptible to this insecticide. partial ...201121501685
do developing malaria parasites manipulate their mosquito host? evidence from infected anopheles funestus (giles) from mozambique.mosquito survival is linked to the activities performed in each oviposition cycle, whilst development of malaria parasites in them is largely temperature dependent. extending the oviposition cycle of the mosquito, even as a side effect of normal development of the parasite, may enhance malaria transmission. a study was therefore undertaken to compare the time spent before returning to feed among infected and uninfected host seeking anopheles funestus from a village in southern mozambique. the st ...201121511315
divergent transcriptional response to thermal stress by anopheles gambiae larvae carrying alternative arrangements of inversion 2la.the african malaria mosquito anopheles gambiae is polymorphic for chromosomal inversion 2la, whose frequency strongly correlates with degree of aridity across environmental gradients. recent physiological studies have associated 2la with resistance to desiccation in adults and thermal stress in larvae, consistent with its proposed role in aridity tolerance. however, the genetic basis of these traits remains unknown. to identify genes that could be involved in the differential response to thermal ...201121535279
the emergence of insecticide resistance in central mozambique and potential threat to the successful indoor residual spraying malaria control programme.abstract:201121535872
continuing intense malaria transmission in northern uganda.abstract. recent reports of reductions in malaria transmission in several african countries have resulted in optimism that malaria can be eliminated in parts of africa where it is currently endemic. it is not known whether these trends are global or whether they are also present in areas where political instability has hindered effective malaria control. we determined malaria parasite carriage and age-dependent antibody responses to plasmodium falciparum antigens in cross-sectional surveys in ap ...201121540398
age-related pyrethroid resistance is not a function of p450 gene expression in the major african malaria vector, anopheles funestus (diptera: culicidae).anopheles funestus is a major vector of malaria in most of the african region. resistance to pyrethroid and carbamate insecticides has been recorded in populations of this species in south africa and mozambique. the p450 gene, cyp6p9, has been shown to be highly transcribed in a permethrin (pyrethroid)-resistant laboratory strain, fumoz-r, originating from southern mozambique. we examined the relationship between pyrethroid resistance and gene transcription levels of two closely related ge ...201122194179
Insecticide resistance in malaria vector mosquitoes at four localities in Ghana, West Africa.ABSTRACT:201121679391
studies on the bionomics of male anopheles gambiae giles and male anopheles funestus giles from southern mozambique.little is known about the fitness of wild male mosquitoes, the females of which are vectors of malaria. the problem of studying male biology has been exacerbated by difficulties associated with catching them. in southern mozambique, however, almost the entire adult population of an. funestus and an. gambiae s.l. rest inside houses. they leave in a dusk exodus, which makes them easy to collect. in 8,348 exit collections from a village from 2003 to 2009, 567,195 male an. funestus and 34,591 male a ...201122129410
contribution of anopheles funestus, an. gambiae and an. nili (diptera: culicidae) to the perennial malaria transmission in the southern and western forest areas of côte d'ivoire.the involvement of members of the anopheles gambiae complex giles and an. funestus giles and an. nili theobald groups in the transmission of plasmodium falciparum was recently investigated in the villages of gbatta and kpéhiri, which lie, respectively, in forest areas in the west and south of côte d'ivoire. adult female mosquitoes were collected, using human landing catches, inside and outside dwellings. after identification and dissection, the heads and thoraces of all the anopheline mosquitoes ...201121294945
microbiome influences on insect host vector competence.insect symbioses lack the complexity and diversity of those associated with higher eukaryotic hosts. symbiotic microbiomes are beneficial to their insect hosts in many ways, including dietary supplementation, tolerance to environmental perturbations and maintenance and/or enhancement of host immune system homeostasis. recent studies have also highlighted the importance of the microbiome in the context of host pathogen transmission processes. here we provide an overview of the relationship betwee ...201121697014
productivity of malaria vectors from different habitat types in the western kenya highlands.mosquito larval source management (lsm) could be a valuable additional tool for integrated malaria vector control especially in areas with focal transmission like the highlands of western kenya if it were not for the need to target all potential habitats at frequent intervals. the ability to determine the productivity of malaria vectors from identified habitats might be used to target lsm only at productive ones.201121559301
arm-specific dynamics of chromosome evolution in malaria mosquitoes.abstract:201121473772
An insight into the sialome of Simulium guianense (DIPTERA:SIMULIIDAE), the main vector of River Blindness Disease in Brazil.ABSTRACT: BACKGROUND: Little is known about the composition and function of the saliva in black flies such as Simulium guianense, the main vector of river blindness disease in Brazil. The complex salivary potion of hematophagous arthropods counteracts their host's hemostasis, inflammation, and immunity. RESULTS: Transcriptome analysis revealed ubiquitous salivary protein families - such as the Antigen-5, Yellow, Kunitz domain, and serine proteases--in the S. guianense sialotranscriptome. Insec ...201122182526
changing patterns of malaria epidemiology between 2002 and 2010 in western kenya: the fall and rise of malaria.the impact of insecticide treated nets (itns) on reducing malaria incidence is shown mainly through data collection from health facilities. routine evaluation of long-term epidemiological and entomological dynamics is currently unavailable. in kenya, new policies supporting the provision of free itns were implemented nationwide in june 2006. to evaluate the impacts of itns on malaria transmission, we conducted monthly surveys in three sentinel sites with different transmission intensities in wes ...201121629783
calpain chronicle--an enzyme family under multidisciplinary characterization.calpain is an intracellular ca2+-dependent cysteine protease (ec 3.4.22.17; clan ca, family c02) discovered in 1964. it was also called canp (ca2+-activated neutral protease) as well as casf, cdp, kaf, etc. until 1990. calpains are found in almost all eukaryotes and a few bacteria, but not in archaebacteria. calpains have a limited proteolytic activity, and function to transform or modulate their substrates' structures and activities; they are therefore called, "modulator proteases." in the huma ...201121670566
anopheles gambiae odorant binding protein crystal complex with the synthetic repellent deet: implications for structure-based design of novel mosquito repellents.insect odorant binding proteins (obps) are the first components of the olfactory system to encounter and bind attractant and repellent odors emanating from various sources for presentation to olfactory receptors, which trigger relevant signal transduction cascades culminating in specific physiological and behavioral responses. for disease vectors, particularly hematophagous mosquitoes, repellents represent important defenses against parasitic diseases because they effect a reduction in the rate ...201121671117
malaria epidemiology in the ahafo area of ghana.abstract: background: plasmodium falciparum malaria remains endemic in sub-saharan africa including ghana. the epidemiology of malaria in special areas, such as mining areas needs to be monitored and controlled. newmont ghana gold limited is conducting mining activities in the brong ahafo region of ghana that may have an impact on the diseases such as malaria in the mining area. methods: prior to the start of mining activities, a cross-sectional survey was conducted in 2006/2007 to determine mal ...201121801344
outdoor host seeking behaviour of anopheles gambiae mosquitoes following initiation of malaria vector control on bioko island, equatorial guinea.abstract:201121736750
a cryptic subgroup of anopheles gambiae is highly susceptible to human malaria parasites.population subgroups of the african malaria vector anopheles gambiae have not been comprehensively characterized owing to the lack of unbiased sampling methods. in the arid savanna zone of west africa, where potential oviposition sites are scarce, widespread collection from larval pools in the peridomestic human habitat yielded a comprehensive genetic survey of local a. gambiae population subgroups, independent of adult resting behavior and ecological preference. a previously unknown subgroup of ...201121292978
hdv-like self-cleaving ribozymes.hdv ribozymes catalyze their own scission from the transcript during rolling circle replication of the hepatitis delta virus. in vitro selection of self-cleaving ribozymes from a human genomic library revealed an hdv-like ribozyme in the second intron of the human cpeb3 gene and recent results suggest that this rna affects episodic memory performance. bioinformatic searches based on the secondary structure of the hdv/cpeb3 fold yielded numerous functional ribozymes in a wide variety of organisms ...201121734469
evaluation of two methods of estimating larval habitat productivity in western kenya highlands.malaria vector intervention and control programs require reliable and accurate information about vector abundance and their seasonal distribution. the availability of reliable information on the spatial and temporal productivity of larval vector habitats can improve targeting of larval control interventions and our understanding of local malaria transmission and epidemics. the main objective of this study was to evaluate two methods of estimating larval habitat productivity in the western kenyan ...201121682875
localization of two na(+)- or k(+)-h(+) antiporters, agnha1 and agnha2, in anopheles gambiae larval malpighian tubules and the functional expression of agnha2 in yeast.the newly identified metazoan na(+)/h(+) antiporter (nha) family is represented by two paralogues, agnha1 and agnha2, in the genome of the african malaria mosquito, anopheles gambiae. both antiporters are postulated to be electrophoretic i.e. voltage-driven. agnha1 was first cloned from an. gambiae larvae and immunolocalized with respect to the h(+) v-atpase by the harvey laboratory. little is known about the properties of nha1s; attempts to characterize agnha1 in na(+)/h(+) exchanger (nhe)-lack ...201122206887
a review of mixed malaria species infections in anopheline mosquitoes.in patients with malaria mixed species infections are common and under reported. in pcr studies conducted in asia mixed infection rates often exceed 20%. in south-east asia, approximately one third of patients treated for falciparum malaria experience a subsequent plasmodium vivax infection with a time interval suggesting relapse. it is uncertain whether the two infections are acquired simultaneously or separately. to determine whether mixed species infections in humans are derived from mainly f ...201121880138
Bionomics of sympatric chromosomal forms of Anopheles funestus (Diptera: Culicidae).Anopheles funestus is one of the major vectors of malaria in Africa. Cytogenetic studies conducted on populations from West Africa have shown variable degrees of polymorphism with a genetic structure leading to the description of two chromosomal forms called "Folonzo" and "Kiribina" that exhibit limited gene flow. Because studies on allopatric populations showed bionomical heterogeneities, the present study was undertaken during three consecutive years (2006, 2007, and 2008) in an area of sympat ...201122129405
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