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epidemiology of malaria in an area of seasonal transmission in niger and implications for the design of a seasonal malaria chemoprevention strategy.few data are available about malaria epidemiological situation in niger. however, implementation of new strategies such as vaccination or seasonal treatment of a target population requires the knowledge of baseline epidemiological features of malaria. a population-based study was conducted to provide better characterization of malaria seasonal variations and population groups the most at risk in this particular area.201324172107
temporal and micro-spatial heterogeneity in the distribution of anopheles vectors of malaria along the kenyan coast.the distribution of anopheline mosquitoes is determined by temporally dynamic environmental and human-associated variables, operating over a range of spatial scales. macro-spatial short-term trends are driven predominantly by prior (lagged) seasonal changes in climate, which regulate the abundance of suitable aquatic larval habitats. micro-spatial distribution is determined by the location of these habitats, proximity and abundance of available human bloodmeals and prevailing micro-climatic cond ...201324330615
the efficacy of long-lasting nets with declining physical integrity may be compromised in areas with high levels of pyrethroid resistance.long-lasting insecticide-treated mosquito nets (llins) are a primary malaria prevention strategy in sub-saharan africa. however, emergence of insecticide resistance threatens the effectiveness of llins.201324156715
reliability of school surveys in estimating geographic variation in malaria transmission in the western kenyan highlands.school surveys provide an operational approach to assess malaria transmission through parasite prevalence. there is limited evidence on the comparability of prevalence estimates obtained from school and community surveys carried out at the same locality.201324143250
projected impacts of climate change on environmental suitability for malaria transmission in west africa.climate change is expected to affect the distribution of environmental suitability for malaria transmission by altering temperature and rainfall patterns; however, the local and global impacts of climate change on malaria transmission are uncertain.201324043443
the clip-domain serine protease homolog spclip1 regulates complement recruitment to microbial surfaces in the malaria mosquito anopheles gambiae.the complement c3-like protein tep1 of the mosquito anopheles gambiae is required for defense against malaria parasites and bacteria. two forms of tep1 are present in the mosquito hemolymph, the full-length tep1-f and the proteolytically processed tep1(cut) that is part of a complex including the leucine-rich repeat proteins lrim1 and apl1c. here we show that the non-catalytic serine protease spclip1 is a key regulator of the complement-like pathway. spclip1 is required for accumulation of tep1 ...201324039584
community-wide distribution of long-lasting insecticidal nets can halt transmission of lymphatic filariasis in southeastern nigeria.lymphatic filariasis (lf) in rural southeastern nigeria is transmitted mainly by anopheles spp. mosquitoes. potential coinfection with loa loa in this area has prevented use of ivermectin in the mass drug administration (mda) strategy for lf elimination because of potential severe adverse l. loa-related reactions. this study determined if long-lasting insecticidal net (llin) distribution programs for malaria would interrupt lf transmission in such areas, without need for mda. monthly entomologic ...201323939708
insulin receptor-like ectodomain genes and splice variants are found in both arthropods and human brain cdna.truncated receptor ectodomains have been described for several classes of cell surface receptors, including those that bind to growth factors, cytokines, immunoglobulins, and adhesion molecules. soluble receptor isoforms are typically generated by proteolytic cleavage of the cell surface receptor or by alternative splicing of rna transcripts arising from the same gene encoding the full-length receptor. both the epidermal growth factor receptor (egfr) and the insulin receptor (insr) families prod ...201327375681
transcriptome deep-sequencing and clustering of expressed isoforms from favia corals.genomic and transcriptomic sequence data are essential tools for tackling ecological problems. using an approach that combines next-generation sequencing, de novo transcriptome assembly, gene annotation and synthetic gene construction, we identify and cluster the protein families from favia corals from the northern red sea.201323937070
inter-epidemic transmission of rift valley fever in livestock in the kilombero river valley, tanzania: a cross-sectional survey.in recent years, evidence of rift valley fever (rvf) transmission during inter-epidemic periods in parts of africa has increasingly been reported. the inter-epidemic transmissions generally pass undetected where there is no surveillance in the livestock or human populations. we studied the presence of and the determinants for inter-epidemic rvf transmission in an area experiencing annual flooding in southern tanzania.201323951376
a sticky situation: the unexpected stability of malaria elimination.malaria eradication involves eliminating malaria from every country where transmission occurs. current theory suggests that the post-elimination challenges of remaining malaria-free by stopping transmission from imported malaria will have onerous operational and financial requirements. although resurgent malaria has occurred in a majority of countries that tried but failed to eliminate malaria, a review of resurgence in countries that successfully eliminated finds only four such failures out of ...201323798693
preventive chemotherapy as a strategy for elimination of neglected tropical parasitic diseases: endgame challenges.global efforts to address neglected tropical diseases (ntds) were stimulated in january 2012 by the london declaration at which 22 partners, including the bill & melinda gates foundation, world bank, world health organization (who) and major pharmaceutical companies committed to sustaining and expanding ntd programmes to eliminate or eradicate 11 ntds by 2020 to achieve the goals outlined in the recently published who road map. here, we present the current context of preventive chemotherapy for ...201323798692
modest additive effects of integrated vector control measures on malaria prevalence and transmission in western kenya.the effect of integrating vector larval intervention on malaria transmission is unknown when insecticide-treated bed-net (itn) coverage is very high, and the optimal indicator for intervention evaluation needs to be determined when transmission is low.201323870708
identification and expression profile analysis of odorant binding proteins in the oriental fruit fly bactrocera dorsalis.olfaction is crucial in many insects for critical behaviors, including those regulating survival and reproduction. insect odorant-binding proteins (obps) function in the first step of the olfactory system and play an essential role in the perception of odorants, such as pheromones and host chemicals. the oriental fruit fly, bactrocera dorsalis, is a destructive fruit-eating pest, due to its wide host range of up to 250 different types of fruits and vegetables, and this fly causes severe economic ...201323867609
non-ltr retrotransposons and microsatellites: partners in genomic variation.the human genome is laden with both non-ltr (long-terminal repeat) retrotransposons and microsatellite repeats. both types of sequences are able to, either actively or passively, mutagenize the genomes of human individuals and are therefore poised to dynamically alter the human genomic landscape across generations. non-ltr retrotransposons, such as l1 and alu, are a major source of new microsatellites, which are born both concurrently and subsequently to l1 and alu integration into the genome. l ...201324195012
inland valley rice production systems and malaria infection and disease in the forest region of western côte d'ivoire.this study aimed to determine the epidemiological impact of rice cultivation in inland valleys on malaria in the forest region of western côte d'ivoire. the importance of malaria was compared in terms of prevalence and parasite density of infections and also in terms of clinical malaria incidence between three agro-ecosystems: (i) uncultivated inland valleys, (r0), (ii) inland valleys with one annual rice cultivation in the rainy season, (r1) and (iii) developed inland valleys with two annual ri ...201323841911
analysis of whitefly transcriptional responses to beauveria bassiana infection reveals new insights into insect-fungus interactions.the fungal pathogen, beauveria bassiana, is an efficient biocontrol agent against a variety of agricultural pests. a thorough understanding of the basic principles of insect-fungus interactions may enable the genetic modification of beauveria bassiana to enhance its virulence. however, the molecular mechanism of insect response to beauveria bassiana infection is poorly understood, let alone the identification of fungal virulent factors involved in pathogenesis.201323861870
changes in the burden of malaria following scale up of malaria control interventions in mutasa district, zimbabwe.to better understand trends in the burden of malaria and their temporal relationship to control activities, a survey was conducted to assess reported cases of malaria and malaria control activities in mutasa district, zimbabwe.201323815862
evidence for gene duplication in the voltage-gated sodium channel gene of aedes aegypti.mutations in the voltage-gated sodium channel gene (nav), known as kdr mutations, are associated with pyrethroid and ddt insecticide resistance in a number of species. in the mosquito dengue vector aedes aegypti, besides kdr, other polymorphisms allowed grouping aanav sequences as type 'a' or 'b'. here, we point a series of evidences that these polymorphisms are actually involved in a gene duplication event.201324481195
marked biological differences between insecticide resistant and susceptible strains of anopheles funestus infected with the murine parasite plasmodium berghei.anopheles funestus is one of the major malaria vectors in africa but research on this species has been restricted due to the lack of viable laboratory colonies. the vectorial capacity of natural populations of an. funestus is well known but its ability to host plasmodium in the laboratory and the development cycle of the parasite within this mosquito species was, until very recently, unknown. in this study we compared laboratory strains of an. funestus that were resistant and susceptible to pyre ...201323782642
a first report of anopheles funestus sibling species in western kenya highlands.understanding disease vector composition is of priority in designing effective disease control programs. in integrated vector control management, understanding of disease vector species among species complexes simplifies priorities for effective control tools selection. this study identified members of the anopheles funestus complex sampled in western kenya from 2002 to 2011 from different breeding sites. larval sampling was carried out using the standard dipper (350ml) in larval habitats in wes ...201323792011
detection of clade types (clades i and ii) within anopheles funestus sensu stricto by the hydrolysis probe analysis (taqman assay).recent studies presented two clades (clades i and ii) within the major malaria vector, anopheles funestus s.s. on the mitochondrial dna. we describe a hydrolysis probe analysis (taqman assay) method for the rapid identification of these two clades.201323758959
asymptomatic plasmodium infection and cognition among primary schoolchildren in a high malaria transmission setting in uganda.asymptomatic parasitemia is common among schoolchildren living in areas of high malaria transmission, yet little is known about its effect on cognitive function in these settings. to investigate associations between asymptomatic parasitemia, anemia, and cognition among primary schoolchildren living in a high malaria transmission setting, we studied 740 children enrolled in a clinical trial in tororo, uganda. parasitemia, measured by thick blood smears, was present in 30% of the children. infecte ...201323589533
synergist bioassays: a simple method for initial metabolic resistance investigation of field anopheles gambiae s.l. populations.metabolic resistance and the potential role of permeability-glycoprotein (p-gp) efflux pumps were investigated in a pyrethroid-resistant wild anopheles gambiae s.l. tiassalé population, using who susceptibility assays with deltamethrin (0.05%), with and without pre-exposure to synergists. the synergists used included an inhibitor of p-glycoprotein efflux pumps (verapamil), an inhibitor of esterases (en 16-5), and an inhibitor of p450s and esterases (piperonyl butoxide). pre-exposure to verapamil ...201324191946
predicting the current and future potential distributions of lymphatic filariasis in africa using maximum entropy ecological niche modelling.modelling the spatial distributions of human parasite species is crucial to understanding the environmental determinants of infection as well as for guiding the planning of control programmes. here, we use ecological niche modelling to map the current potential distribution of the macroparasitic disease, lymphatic filariasis (lf), in africa, and to estimate how future changes in climate and population could affect its spread and burden across the continent. we used 508 community-specific infecti ...201222359670
spatially explicit analyses of anopheline mosquitoes indoor resting density: implications for malaria control.the question of sampling and spatial aggregation of malaria vectors is central to vector control efforts and estimates of transmission. spatial patterns of anopheline populations are complex because mosquitoes' habitats and behaviors are strongly heterogeneous. analyses of spatially referenced counts provide a powerful approach to delineate complex distribution patterns, and contributions of these methods in the study and control of malaria vectors must be carefully evaluated.201222348131
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
mapping the receptivity of malaria risk to plan the future of control in somalia.to measure the receptive risks of malaria in somalia and compare decisions on intervention scale-up based on this map and the more widely used contemporary risk maps.201222855625
analysis of genes expression of spodoptera exigua larvae upon acmnpv infection.the impact of autographa californica multicapsid nucleopolyhedrovirus (acmnpv) infection on host gene expression in spodoptera exigua 4th instar larvae was investigated through the use of 454 sequencing-based rna-seq of cdna libraries developed from insects challenged with active acmnpv or heat-inactivated acmnpv.201222860129
increased risks of malaria due to limited residual life of insecticide and outdoor biting versus protection by combined use of nets and indoor residual spraying on bioko island, equatorial guinea.malaria is endemic on bioko island, equatorial guinea, with year-round transmission. in 2004 an intensive malaria control strategy primarily based on indoor residual spraying (irs) was launched. the limited residual life of irs poses particular challenges in a setting with year-round transmission, such as bioko. recent reports of outdoor biting by anopheles gambiae are an additional cause for concern. in this study, the effect of the short residual life of bendiocarb insecticide and of children ...201222835049
identification of distant agouti-like sequences and re-evaluation of the evolutionary history of the agouti-related peptide (agrp).the agouti-like peptides including agrp, asip and the teleost-specific a2 (asip2 and agrp2) peptides have potent and diverse functional roles in feeding, pigmentation and background adaptation mechanisms. there are contradictory theories about the evolution of the agouti-like peptide family as well the nomenclature. here we performed comprehensive mining and annotation of vertebrate agouti-like sequences. we identified a2 sequences from salmon, trout, seabass, cod, cichlid, tilapia, gilt-headed ...201222815886
thermal limits of wild and laboratory strains of two african malaria vector species, anopheles arabiensis and anopheles funestus.malaria affects large parts of the developing world and is responsible for almost 800,000 deaths annually. as climates change, concerns have arisen as to how this vector-borne disease will be impacted by changing rainfall patterns and warming temperatures. despite the importance and controversy surrounding the impact of climate change on the potential spread of this disease, little information exists on the tolerances of several of the vector species themselves.201222770378
modeling the role of environmental variables on the population dynamics of the malaria vector anopheles gambiae sensu stricto.the impact of weather and climate on malaria transmission has attracted considerable attention in recent years, yet uncertainties around future disease trends under climate change remain. mathematical models provide powerful tools for addressing such questions and understanding the implications for interventions and eradication strategies, but these require realistic modeling of the vector population dynamics and its response to environmental variables.201222877154
pyrethroid resistance in anopheles gambiae s.s. and anopheles arabiensis in western kenya: phenotypic, metabolic and target site characterizations of three populations.field and laboratory investigations revealed phenotypic, target site and metabolic resistance to permethrin in an anopheles gambiae s.s. (diptera: culicidae) population in bungoma district, a region in western kenya in which malaria is endemic and rates of ownership of insecticide-treated bednets are high. the sensitivity of individual an. gambiae s.l. females as indicated in assays using world health organization (who) test kits demonstrated reduced mortality in response to permethrin, deltamet ...201222861380
malaria in east african highlands during the past 30 years: impact of environmental changes.east african highlands are one of the most populated regions in africa. the population densities in the highlands ranged between 158 persons/km(2) in ethiopia and 410 persons/km(2) in rwanda. according to the united nations population fund, the region has the world's highest population growth rate. these factors are likely behind the high rates of poverty among the populations. as there were no employment opportunities other than agricultural, this demographic pressure of poor populations have i ...201222934065
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
the efficacy of vectron 20 wp, etofenprox, for indoor residual spraying in areas of high vector resistance to pyrethroids and organochlorines in zambia.the selection of insecticide resistance in malaria vectors has the potential to compromise any insecticide-based vector control programme. to ensure that the insecticides used for indoor residual spraying and insecticide-treated nets in zambia remain effective and their choice is evidence based, insecticide resistance surveillance and monitoring are essential. this study assessed and compared the residual efficacy of etofenprox (vectron 20 wp), an ether pyrethroid, at 0.1 g/m(2) with pyrethroids ...201224967135
population genetic structure of the malaria vector anopheles funestus, in a recently re-colonized area of the senegal river basin and human-induced environmental changes.anopheles funestus is one of the major malaria vectors in tropical africa. because of several cycles of drought events that occurred during the 1970s, this species had disappeared from many parts of sahelian africa, including the senegal river basin. however, this zone has been re-colonized during the last decade by an. funestus, following the implementation of two dams on the senegal river. previous studies in that area revealed heterogeneity at the biological and chromosomal level among these ...201222950576
positional cloning of rp2 qtl associates the p450 genes cyp6z1, cyp6z3 and cyp6m7 with pyrethroid resistance in the malaria vector anopheles funestus.pyrethroid resistance in anopheles funestus is threatening malaria control in africa. elucidation of underlying resistance mechanisms is crucial to improve the success of future control programs. a positional cloning approach was used to identify genes conferring resistance in the uncharacterised rp2 quantitative trait locus (qtl) previously detected in this vector using f6 advanced intercross lines (ail). a 113 kb bac clone spanning rp2 was identified and sequenced revealing a cluster of 15 p45 ...201222948188
real-time pcr assay for discrimination of plasmodium ovale curtisi and plasmodium ovale wallikeri in the ivory coast and in the comoros islands.plasmodium ovale is one of the five malaria species infecting humans. recent data have shown that the name of this neglected species masks two distinct genotypes also called curtisi and wallikeri. some authors show that these species could be sympatric. these two subspecies are not differentiated by microscopy techniques and malaria rapid diagnostic tests. this diagnostic defect is the result of low parasitaemia, antigenic polymorphism and absence of antibodies performance and requires the use o ...201222947418
malaria control in south africa 2000-2010: beyond mdg6.malaria is one of the key targets within goal 6 of the millennium development goals (mdgs), whereby the disease needs to be halted and reversed by the year 2015. several other international targets have been set, however the mdgs are universally accepted, hence it is the focus of this manuscript.201222913727
sustainable malaria control: transdisciplinary approaches for translational applications.with the adoption of the global malaria action plan, several countries are moving from malaria control towards elimination and eradication. however, the sustainability of some of the approaches taken may be questionable. here, an overview of malaria control and elimination strategies is provided and the sustainability of each in context of vector- and parasite control is assessed. from this, it can be concluded that transdisciplinary approaches are essential for sustained malaria control and eli ...201223268712
the feasibility of malaria elimination in south africa.following the last major malaria epidemic in 2000, malaria incidence in south africa has declined markedly. the decrease has been so emphatic that south africa now meets the world health organization (who) threshold for malaria elimination. given the millennium development goal of reversing the spread of malaria by 2015, south africa is being urged to adopt an elimination agenda. this study aimed to determine the appropriateness of implementing a malaria elimination programme in present day sout ...201223253091
the fitness of african malaria vectors in the presence and limitation of host behaviour.host responses are important sources of selection upon the host species range of ectoparasites and phytophagous insects. however little is known about the role of host responses in defining the host species range of malaria vectors. this study aimed to estimate the relative importance of host behaviour to the feeding success and fitness of african malaria vectors, and assess its ability to predict their known host species preferences in nature.201223253167
anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. this study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western kenya.201223272215
directionally selected cytochrome p450 alleles are driving the spread of pyrethroid resistance in the major malaria vector anopheles funestus.pyrethroid insecticides are critical for malaria control in africa. however, resistance to this insecticide class in the malaria vector anopheles funestus is spreading rapidly across africa, threatening the success of ongoing and future malaria control programs. the underlying resistance mechanisms driving the spread of this resistance in wild populations remain largely unknown. here, we show that increased expression of two tandemly duplicated p450 genes, cyp6p9a and cyp6p9b, is the main mechan ...201223248325
malaria parasite diversity and transmission intensity affect development of parasitological immunity in a mathematical model.the development of parasitological immunity against malaria affects the ability to detect infection, the efficiency of the local human parasite reservoir at infecting mosquitoes, and the response to reintroduction of parasites to previously cleared areas. observations of similar age-trends in detected prevalence and mean parasitaemia across more than an order-of-magnitude of variation in baseline transmission complicate simple exposure-driven explanations.201223241282
implications of bio-efficacy and persistence of insecticides when indoor residual spraying and long-lasting insecticide nets are combined for malaria prevention.bio-efficacy and residual activity of insecticides used for indoor residual spraying (irs) and long-lasting insecticide nets (llins) were assessed against laboratory-reared and wild populations of the malaria vector, anopheles arabiensis in south eastern tanzania. implications of the findings are examined in the context of potential synergies and redundancies where irs and llins are combined.201223164062
biochemical characterization of anopheles gambiae srpn6, a malaria parasite invasion marker in mosquitoes.serine proteinase inhibitors of the serpin family are well known as negative regulators of hemostasis, thrombolysis and innate immune responses. additionally, non-inhibitory serpins serve functions as chaperones, hormone transporters, or anti-angiogenic factors. in the african malaria mosquito, anopheles gambiae s.s., at least three serpins (srpns) are implicated in the innate immune response against malaria parasites. based on reverse genetic and cell biological analyses, agsrpn6 limits parasit ...201223152794
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
impact of pyrethroid resistance on operational malaria control in malawi.the impact of insecticide resistance on insect-borne disease programs is difficult to quantify. the possibility of eliminating malaria in high-transmission settings is heavily dependent on effective vector control reducing disease transmission rates. pyrethroids are the dominant insecticides used for malaria control, with few options for their replacement. their failure will adversely affect our ability to control malaria. pyrethroid resistance has been selected in malawi over the last 3 y in th ...201223118337
simulation of malaria epidemiology and control in the highlands of western kenya.models of plasmodium falciparum malaria epidemiology that provide realistic quantitative predictions of likely epidemiological outcomes of existing vector control strategies have the potential to assist in planning for the control and elimination of malaria. this work investigates the applicability of mathematical modelling of malaria transmission dynamics in rachuonyo south, a district with low, unstable transmission in the highlands of western kenya.201223107070
characterization of a chitin synthase encoding gene and effect of diflubenzuron in soybean aphid, aphis glycines.chitin synthases are critical enzymes for synthesis of chitin and thus for subsequent growth and development in insects. we identified the cdna of chitin synthase gene (chs) in aphis glycines, the soybean aphid, which is a serious pest of soybean. the full-length cdna of chs in a. glycines (aychs) was 5802 bp long with an open reading frame of 4704 bp that encoded for a 1567 amino acid residues protein. the predicted aychs protein had a molecular mass of 180.05 kda and its amino acid sequence co ...201223139631
the effects of oviposition-site deprivation on anopheles gambiae reproduction.the african malaria mosquito, anopheles gambiae, depends on availability of suitable surface water for oviposition. short and long dry spells occur throughout the year in many parts of its range that limit its access to oviposition sites. although not well understood, oviposition-site deprivation has been found to rapidly reduce egg batch size and hatch rate of several mosquito species. we conducted laboratory experiments to assess these effects of oviposition-site deprivation on an. gambiae and ...201223072301
reconsideration of anopheles rivulorum as a vector of plasmodium falciparum in western kenya: some evidence from biting time, blood preference, sporozoite positive rate, and pyrethroid resistance.anopheles gambiae, an. arabiensis, and an. funestus are widespread malaria vectors in africa. anopheles rivulorum is the next most widespread species in the an. funestus group. the role of an. rivulorum as a malaria vector has not been fully studied, although it has been found to be a minor or opportunistic transmitter of plasmodium falciparum.201223050856
footprints of positive selection associated with a mutation (n1575y) in the voltage-gated sodium channel of anopheles gambiae.insecticide resistance is an ideal model to study the emergence and spread of adaptative variants. in the african malaria mosquito, anopheles gambiae, this is complemented by a strong public health rationale. in this insect, resistance to pyrethroid and ddt insecticides is strongly associated with the mutations l1014f and l1014s within the para voltage-gated sodium channel (vgsc). across much of west africa, 1014f frequency approaches fixation. here, we document the emergence of a mutation, n157 ...201222493253
selection of mosquito life-histories: a hidden weapon against malaria?there has recently been a substantial decline in malaria incidence in much of africa. while the decline can clearly be linked to increasing coverage of mosquito vector control interventions and effective drug treatment in most settings, the ubiquity of reduction raises the possibility that additional ecological and associated evolutionary changes may be reinforcing the effectiveness of current vector control strategies in previously unanticipated ways.201222471997
a refined estimate of the malaria burden in niger.the health authorities of niger have implemented several malaria prevention and control programmes in recent years. these interventions broadly follow who guidelines and international recommendations and are based on interventions that have proved successful in other parts of africa. most performance indicators are satisfactory but, paradoxically, despite the mobilization of considerable human and financial resources, the malaria-fighting programme in niger seems to have stalled, as it has not y ...201222453027
exploiting the behaviour of wild malaria vectors to achieve high infection with fungal biocontrol agents.control of mosquitoes that transmit malaria has been the mainstay in the fight against the disease, but alternative methods are required in view of emerging insecticide resistance. entomopathogenic fungi are candidate alternatives, but to date, few trials have translated the use of these agents to field-based evaluations of their actual impact on mosquito survival and malaria risk. mineral oil-formulations of the entomopathogenic fungi metarhizium anisopliae and beauveria bassiana were applied u ...201222449130
utilization of combined remote sensing techniques to detect environmental variables influencing malaria vector densities in rural west africa.the use of remote sensing has found its way into the field of epidemiology within the last decades. with the increased sensor resolution of recent and future satellites new possibilities emerge for high resolution risk modeling and risk mapping.201222443452
antibodies to malaria vaccine candidates are associated with chloroquine or sulphadoxine/pyrimethamine treatment efficacy in children in an endemic area of burkina faso.patient immune status is thought to affect the efficacy of anti-malarial chemotherapy. this is a subject of some importance, since evidence of immunity-related interactions may influence our use of chemotherapy in populations with drug resistance, as well as assessment of the value of suboptimal vaccines. the study aim was to investigate relationship between antibodies and anti-malarial drug treatment outcomes.201222439695
first malaria infections in a cohort of infants in benin: biological, environmental and genetic determinants. description of the study site, population methods and preliminary results.malaria infection of the placenta during pregnancy was found to be associated with infant susceptibility to malaria. other factors such as the intensity of malaria transmission and the nutritional status of the child might also play a role, which has not been adequately taken into account in previous studies. the aim of this study was to assess precisely the parts played by environmental, nutritional and biological determinants in first malaria infections, with a special interest in the role of ...201222403339
identification and characterization of two chitin synthase genes in african malaria mosquito, anopheles gambiae.chitin synthase (chs) represents an attractive target site for combating insect pests as insect growth and development are strictly dependent on precisely tuned chitin biosynthesis and this pathway is absent in humans and other vertebrates. current knowledge on chs in insects, especially their structures, functions, and regulations is still very limited. we report the identification and characterization of two chitin synthase genes, agchs1 and agchs2, in african malaria mosquito, anopheles gambi ...201222683441
integrated mosquito larval source management reduces larval numbers in two highland villages in western kenya.in western kenya, malaria remains one of the major health problems and its control remains an important public health measure. malaria control is by either use of drugs to treat patients infected with malaria parasites or by controlling the vectors. vector control may target the free living adult or aquatic (larval) stages of mosquito. the most commonly applied control strategies target indoor resting mosquitoes. however, because mosquitoes spend a considerable time in water, targeting the aquat ...201222607227
dry season reproductive depression of anopheles gambiae in the sahel.the african malaria mosquito, anopheles gambiae, is widespread south of the sahara including in dry savannahs and semi-arid environments where no surface water exists for several months a year. adults of the m form of an. gambiae persist through the long dry season, when no surface waters are available, by increasing their maximal survival from 4 weeks to 7 months. dry season diapause (aestivation) presumably underlies this extended survival. diapause in adult insects is intrinsically linked to ...201222609421
identification and classification of detoxification enzymes from culex quinquefasciatus (diptera: culicidae).molecular characterization of the insecticide resistance has become a hot research topic ever since the first disease transmitting arthropod (anopheles gambiae) genome sequence has unveiled in 2002. a recent publication of the culex quinquefasciatus genome sequence has opened up new opportunities for molecular and comparative genomic analysis of multiple mosquito genomes to characterize the insecticide resistance. here, we utilized a whole genome sequence of cx. quinquefasciatus to identify puta ...201222715314
haemoglobin variants and plasmodium falciparum malaria in children under five years of age living in a high and seasonal malaria transmission area of burkina faso.genetic factors play a key role in determining resistance/susceptibility to infectious disease. susceptibility of the human host to malaria infection has been reported to be influenced by genetic factors, which could be confounders if not taken into account in the assessment of the efficacy of interventions against malaria. this study aimed to assess the relationship between haemoglobin genotypes and malaria in children under five years in a site being characterized for future malaria vaccine tr ...201222559271
cholinergic and non-cholinergic functions of two acetylcholinesterase genes revealed by gene-silencing in tribolium castaneum.we compared biological functions of two acetylcholinesterase genes (tcace1 and tcace2) in tribolium castaneum, a globally distributed major pest of stored grain products and an emerging model organism, by using rna interference. although both genes expressed at all developmental stages and mainly in the brain, the transcript level of tcace1 was 1.2- to 8.7-fold higher than that of tcace2, depending on developmental stages. silencing tcace1 in 20-day larvae led to 100% mortality within two weeks ...201222371826
intermittent preventive treatment with sulfadoxine-pyrimethamine does not modify plasma cytokines and chemokines or intracellular cytokine responses to plasmodium falciparum in mozambican children.cytokines and chemokines are key mediators of anti-malarial immunity. we evaluated whether intermittent preventive treatment in infants with sulfadoxine-pyrimethamine (ipti-sp) had an effect on the acquisition of these cellular immune responses in mozambican children. multiple cytokines and chemokines were quantified in plasma by luminex, and antigen-specific cytokine production in whole blood was determined by intracellular cytokine staining and flow cytometry, at ages 5, 9, 12 and 24 months.201222280502
dry season determinants of malaria disease and net use in benin, west africa.to achieve malaria eradication, control efforts have to be sustained even when the incidence of malaria cases becomes low during the dry season. in this work, malaria incidence and its determinants including bed net use were investigated in children of under 5 years of age in 28 villages in southern benin during the dry season.201222291987
changes in malaria morbidity and mortality in mpumalanga province, south africa (2001-2009): a retrospective study.malaria remains a serious epidemic threat in mpumalanga province. in order to appropriately target interventions to achieve substantial reduction in the burden of malaria and ultimately eliminate the disease, there is a need to track progress of malaria control efforts by assessing the time trends and evaluating the impact of current control interventions. this study aimed to assess the changes in the burden of malaria in mpumalanga province during the past eight malaria seasons (2001/02 to 2008 ...201222239855
importance of factors determining the effective lifetime of a mass, long-lasting, insecticidal net distribution: a sensitivity analysis.long-lasting insecticidal nets (llins) reduce malaria transmission by protecting individuals from infectious bites, and by reducing mosquito survival. in recent years, millions of llins have been distributed across sub-saharan africa (ssa). over time, llins decay physically and chemically and are destroyed, making repeated interventions necessary to prevent a resurgence of malaria. because its effects on transmission are important (more so than the effects of individual protection), estimates of ...201222244509
population genetic structure of the major malaria vector anopheles funestus s.s. and allied species in southern africa.anopheles funestus s.s., one of the major malaria vectors in sub-saharan africa, belongs to a group of eleven african species that are morphologically similar at the adult stage, most of which do not transmit malaria. the population structure of an. funestus based on mitochondrial dna data led to the description of two cryptic subdivisions, clade i widespread throughout africa and clade ii known only from mozambique and madagascar. in this study, we investigated five common members of the anophe ...201223216696
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
human antibody response to anopheles saliva for comparing the efficacy of three malaria vector control methods in balombo, angola.human antibody (ab) response to anopheles whole saliva, used as biomarker of anopheles exposure, was investigated over a period of two years (2008-2009), in children between 2 to 9 years old, before and after the introduction of three different malaria vector control methods; deltamethrin treated long lasting impregnated nets (llin) and insecticide treated plastic sheeting (itps)--zero fly®) (itps-zf), deltamethrin impregnated durable (wall) lining (itps-dl--zerovector®) alone, and indoor residu ...201223028499
use of a mixture statistical model in studying malaria vectors density.vector control is a major step in the process of malaria control and elimination. this requires vector counts and appropriate statistical analyses of these counts. however, vector counts are often overdispersed. a non-parametric mixture of poisson model (npmp) is proposed to allow for overdispersion and better describe vector distribution. mosquito collections using the human landing catches as well as collection of environmental and climatic data were carried out from january to december 2009 i ...201223185626
biochemical characterization of chitin synthase activity and inhibition in the african malaria mosquito, anopheles gambiae.chitin synthase (chs) is an important enzyme catalyzing the formation of chitin polymers in all chitin containing organisms and a potential target site for insect pest control. however, our understanding of biochemical properties of insect chss has been very limited. we here report enzymatic and inhibitory properties of chs prepared from the african malaria mosquito, anopheles gambiae. our study, which represents the first time to use a nonradioactive method to assay chs activity in an insect sp ...201223955856
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
the development of insecticide-treated durable wall lining for malaria control: insights from rural and urban populations in angola and nigeria.durable lining (dl) is a deltamethrin-impregnated polyethylene material, which is designed to cover domestic walls that would normally be sprayed with residual insecticide. the operational success of dl as a long-lasting insecticidal substrate will be dependent on a high level of user acceptability as households must maintain correctly installed linings on their walls for several years. preliminary trials were undertaken to identify a material to develop into a marketable wall lining and to asse ...201222989007
megabase-scale inversion polymorphism in the wild ancestor of maize.chromosomal inversions are thought to play a special role in local adaptation, through dramatic suppression of recombination, which favors the maintenance of locally adapted alleles. however, relatively few inversions have been characterized in population genomic data. on the basis of single-nucleotide polymorphism (snp) genotyping across a large panel of zea mays, we have identified an ∼50-mb region on the short arm of chromosome 1 where patterns of polymorphism are highly consistent with a pol ...201222542971
the complete mitochondrial genomes of two ghost moths, thitarodes renzhiensis and thitarodes yunnanensis: the ancestral gene arrangement in lepidoptera.lepidoptera encompasses more than 160,000 described species that have been classified into 45-48 superfamilies. the previously determined lepidoptera mitochondrial genomes (mitogenomes) are limited to six superfamilies of the lineage ditrysia. compared with the ancestral insect gene order, these mitogenomes all contain a trna rearrangement. to gain new insights into lepidoptera mitogenome evolution, we sequenced the mitogenomes of two ghost moths that belong to the non-ditrysian lineage hepialoi ...201222726496
reliability of rapid diagnostic tests in diagnosing pregnancy-associated malaria in north-eastern tanzania.accurate diagnosis and prompt treatment of pregnancy-associated malaria (pam) are key aspects in averting adverse pregnancy outcomes. microscopy is the gold standard in malaria diagnosis, but it has limited detection and availability. when used appropriately, rapid diagnostic tests (rdts) could be an ideal diagnostic complement to microscopy, due to their ease of use and adequate sensitivity in detecting even sub-microscopic infections. polymerase chain reaction (pcr) is even more sensitive, but ...201222720788
airflow attenuation and bed net utilization: observations from africa and asia.qualitative studies suggest that bed nets affect the thermal comfort of users. to understand and reduce this discomfort the effect of bed nets on temperature, humidity, and airflow was measured in rural homes in asia and africa, as well as in an experimental wind tunnel. two investigators with architectural training selected 60 houses in the gambia, tanzania, philippines, and thailand. data-loggers were used to measure indoor temperatures in hourly intervals over a 12 months period. in a subgrou ...201222704585
functional organization and its implication in evolution of the human protein-protein interaction network.based on the distinguishing properties of protein-protein interaction networks such as power-law degree distribution and modularity structure, several stochastic models for the evolution of these networks have been purposed, motivated by the idea that a validated model should reproduce similar topological properties of the empirical network. however, being able to capture topological properties does not necessarily mean it correctly reproduces how networks emerge and evolve. more importantly, th ...201222530615
artemisinin-based combination therapy does not measurably reduce human infectiousness to vectors in a setting of intense malaria transmission.artemisinin-based combination therapy (act) for treating malaria has activity against immature gametocytes. in theory, this property may complement the effect of terminating otherwise lengthy malaria infections and reducing the parasite reservoir in the human population that can infect vector mosquitoes. however, this has never been verified at a population level in a setting with intense transmission, where chronically infectious asymptomatic carriers are common and cured patients are rapidly a ...201222513162
anticholinesterase insecticide retrospective.the anticholinesterase (antiche) organophosphorus (op) and methylcarbamate (mc) insecticides have been used very effectively as contact and systemic plant protectants for seven decades. about 90 of these compounds are still in use - the largest number for any insecticide chemotype or mode of action. in both insects and mammals, ache inhibition and acetylcholine accumulation leads to excitation and death. the cholinergic system of insects is located centrally (where it is protected from ionized o ...201222926007
candidate chemosensory genes in female antennae of the noctuid moth spodoptera littoralis.chemical senses are crucial for all organisms to detect various environmental information. different protein families, expressed in chemosensory organs, are involved in the detection of this information, such as odorant-binding proteins, olfactory and gustatory receptors, and ionotropic receptors. we recently reported an expressed sequence tag (est) approach on male antennae of the noctuid moth, spodoptera littoralis, with which we could identify a large array of chemosensory genes in a species ...201222904672
spatial and temporal dynamics of malaria transmission in rural western kenya.understanding the relationship between plasmodium falciparum malaria transmission and health outcomes requires accurate estimates of exposure to infectious mosquitoes. however, measures of exposure such as mosquito density and entomological inoculation rate (eir) are generally aggregated over large areas and time periods, biasing the outcome-exposure relationship. there are few studies examining the extent and drivers of local variation in malaria exposure in endemic areas.201222541138
characterization of the transcriptome of an ecologically important avian species, the vinous-throated parrotbill paradoxornis webbianus bulomachus (paradoxornithidae; aves).adaptive divergence driven by environmental heterogeneity has long been a fascinating topic in ecology and evolutionary biology. the study of the genetic basis of adaptive divergence has, however, been greatly hampered by a lack of genomic information. the recent development of transcriptome sequencing provides an unprecedented opportunity to generate large amounts of genomic data for detailed investigations of the genetics of adaptive divergence in non-model organisms. herein, we used the illum ...201222530590
assessment of anopheles salivary antigens as individual exposure biomarkers to species-specific malaria vector bites.malaria transmission occurs during the blood feeding of infected anopheline mosquitoes concomitant with a saliva injection into the vertebrate host. in sub-saharan africa, most malaria transmission is due to anopheles funestus s.s and to anopheles gambiae s.l. (mainly anopheles gambiae s.s. and anopheles arabiensis). several studies have demonstrated that the immune response against salivary antigens could be used to evaluate individual exposure to mosquito bites. the aim of this study was to as ...201223276246
igg responses to the gsg6-p1 salivary peptide for evaluating human exposure to anopheles bites in urban areas of dakar region, sénégal.urban malaria can be a serious public health problem in africa. human-landing catches of mosquitoes, a standard entomological method to assess human exposure to malaria vector bites, can lack sensitivity in areas where exposure is low. a simple and highly sensitive tool could be a complementary indicator for evaluating malaria exposure in such epidemiological contexts. the human antibody response to the specific anopheles gsg6-p1 salivary peptide have been described as an adequate tool biomarker ...201222424570
low and seasonal malaria transmission in the middle senegal river basin: identification and characteristics of anopheles vectors.during the last decades two dams were constructed along the senegal river. these intensified the practice of agriculture along the river valley basin. we conducted a study to assess malaria vector diversity, dynamics and malaria transmission in the area.201222269038
evidence for population-specific positive selection on immune genes of anopheles gambiae.host-pathogen interactions can be powerful drivers of adaptive evolution, shaping the patterns of molecular variation at the genes involved. in this study, we sequenced alleles from 28 immune-related loci in wild samples of multiple genetic subpopulations of the african malaria mosquito anopheles gambiae, obtaining unprecedented sample sizes and providing the first opportunity to contrast patterns of molecular evolution at immune-related loci in the recently discovered goundry population to thos ...201223275874
entomological indices of malaria transmission in chikhwawa district, southern malawi.although malaria is highly prevalent throughout malawi, little is known of its transmission dynamics. this paper describes the seasonal activity of the different vectors, human biting indices, sporozoite rates and the entomological inoculation rate in a low-lying rural area in southern malawi.201223171123
a new chromosomal phylogeny supports the repeated origin of vectorial capacity in malaria mosquitoes of the anopheles gambiae complex.understanding phylogenetic relationships within species complexes of disease vectors is crucial for identifying genomic changes associated with the evolution of epidemiologically important traits. however, the high degree of genetic similarity among sibling species confounds the ability to determine phylogenetic relationships using molecular markers. the goal of this study was to infer the ancestral-descendant relationships among malaria vectors and nonvectors of the anopheles gambiae species co ...201223055932
severe and uncomplicated falciparum malaria in children from three regions and three ethnic groups in cameroon: prospective study.to identify the factors that account for differences in clinical outcomes of malaria as well as its relationship with ethnicity, transmission intensity and parasite density.201222727184
prevalence of malaria infection in butajira area, south-central ethiopia.in 2005, the ethiopian government launched a massive expansion of the malaria prevention and control programme. the programme was aimed mainly at the reduction of malaria in populations living below 2,000 m above sea level. global warming has been implicated in the increase in the prevalence of malaria in the highlands. however, there is still a paucity of information on the occurrence of malaria at higher altitudes. the objective of this study was to estimate malaria prevalence in highland area ...201222443307
wind direction and proximity to larval sites determines malaria risk in kilifi district in kenya.studies of the fine-scale spatial epidemiology of malaria consistently identify malaria hotspots, comprising clusters of homesteads at high transmission intensity. these hotspots sustain transmission, and may be targeted by malaria-control programmes. here we describe the spatial relationship between the location of anopheles larval sites and human malaria infection in a cohort study of 642 children, aged 1-10-years-old. our data suggest that proximity to larval sites predict human malaria infec ...201222334077
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