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tsetse and trypanosomosis in africa: the challenges, the opportunities.tsetse-fly and the disease it transmits, trypanosomosis, remain an enormous disease challenge in the 37 countries of sub-saharan africa where the impact continues to be manifest in disease burden, increased level of poverty and decreased agricultural productivity. the impact also extends over an estimated 10 million km2 (a third of the african continent) of land area, a third of which contains some well-watered part of the continent, thus denying humans and livestock of potentially rich arable a ...200919967926
characterisations of odorant-binding proteins in the tsetse fly glossina morsitans morsitans.odorant-binding proteins (obps) play an important role in insect olfaction by mediating interactions between odorants and odorant receptors. we report for the first time 20 obp genes in the tsetse fly glossina morsitans morsitans. qrt-pcr revealed that 8 of these genes were highly transcribed in the antennae. the transcription of these genes in the antennae was significantly lower in males than in females and there was a clear correlation between obp gene transcription and feeding status. starva ...201020012146
population structure of glossina palpalis gambiensis (diptera: glossinidae) between river basins in burkina faso: consequences for area-wide integrated pest management.african animal trypanosomosis is a major obstacle to the development of more efficient and sustainable livestock production systems in west africa. riverine tsetse species such as glossina palpalis gambiensis vanderplank are their major vectors. a wide variety of control tactics is available to manage these vectors, but their elimination will only be sustainable if control is exercised following area-wide integrated pest management (aw-ipm) principles, i.e. the control effort is targeting an ent ...201020060501
evaluation of deltamethrin applications in the control of tsetse and trypanosomosis in the southern rift valley areas of ethiopia.a study aimed at evaluating the efficacy of deltamethrin (0.4% impregnated targets and 1% pour-on formulation) in controlling tsetse and trypanosomosis was carried out in two selected 10km x 10km universal transverse mercator grids of the southern tsetse eradication project (step) area in the southern rift valley of ethiopia. the grids selected were h3 (site i) and g5 (site ii) in two districts of the wolaita zone. the trial was underway from september 2003 to april 2004. the strategy followed t ...201020060647
diversity and spatial distribution of vectors and hosts of t. brucei gambiense in forest zones of, southern cameroon: epidemiological implications.host and vector distribution of trypanosoma brucei gambiense was studied in relation to habitat types and seasons. six (19.35%) of the 31 mammal species recorded in bipindi were reservoir hosts. cercopithecus nictitans was confined to the undisturbed forest and the low intensive shifting cultivation zones, while cephalophus monticola, cephalophus dorsalis, cricetomys gambianus, atherurus africanus and nandinia binotata occurred in all the habitat types. as for vectors of human african trypanosom ...201020067756
[eco-distribution and trypanosoma infection of glossina palpalis palpalis in the banco forest of and its relics, abidjan (côte d'ivoire)].in order to implement an anti-vector programme in the suburb of abidjan (côte d'ivoire), investigations were conducted to assess the tsetse fly densities as well as infection with trypanosomes. catches were carried out during the rainy season and dry season with vavoua traps laid during four consecutive days in different sites (banco forest, abidjan zoological park, area of the university of abobo-adjamé). one species of tsetse fly (glossina polpalis palpalis) and two species of trypanosomes (tr ...200920092060
epidemiological study of canine trypanosomosis in an urban area of ivory coast.following confirmed cases of trypanosomosis in military working dogs, a cross-sectional study was undertaken to evaluate the source of infection and determine the prevalence of canine infection with trypanosoma congolense in the urban focus of abidjan, ivory coast. blood from 123 dogs were collected and subjected to pcr using specific primers for trypanosoma congolense "forest type". in addition, an entomological study was conducted in an urban area near the forest surronding the military camp. ...200920092062
trypanosoma brucei: reduction of gpi-phospholipase c protein during differentiation is dependent on replication of newly transformed cells.the protozoan parasite trypanosoma brucei lives in the bloodstream of vertebrates or in a tsetse fly. expression of a gpi-phospholipase c polypeptide (gpi-plcp) in the parasite is restricted to the bloodstream form. events controlling the amount of gpi-plcp expressed during differentiation are not completely understood. our metabolic "pulse-chase" analysis reveals that gpi-plcp is stable in bloodstream form. however, during differentiation of bloodstream to insect stage (procyclic) t. brucei, tr ...201020109448
molecular characterization of two novel milk proteins in the tsetse fly (glossina morsitans morsitans).milk proteins are an essential component of viviparous reproduction in the tsetse fly. milk proteins are synthesized in and secreted from the milk gland tissue and constitute 50% of the secretions from which the intrauterine larva derives its nourishment. to understand milk protein function and regulation during viviparous reproduction, milk proteins need to be identified and characterized.201020136662
the protease resistant surface (prs) glycoconjugate from trypanosoma congolense has an inositol-acylated glycosylphosphatidylinositol anchor, containing a significant proportion of myristate at the sn-2 position.in the tsetse fly, the surface of trypanosoma congolense parasites is covered by a dense layer of glycosylphosphatidylinositol (gpi)-anchored molecules. these include epgengt procyclin and protease resistant surface molecule (prs), as well as congolense epimastigote-specific protein, cesp, and glutamic acid- and alanine-rich protein (garp). the gpi structures of epgengt and garp have been partially elucidated, but very little is known about prs. we now purified prs and analyzed its gpi lipid str ...201020138924
population structuring of the tsetse glossina tachinoides resulting from landscape fragmentation in the mouhoun river basin, burkina faso.the impact of landscape fragmentation resulting from human- and climate-mediated factors on the structure of a population of glossina tachinoides westwood (diptera: glossinidae) in the mouhoun river basin, burkina faso, was investigated. allele frequencies at five microsatellite loci were compared in four populations. the average distance between samples was 72 km. the sampling points traversed an ecological cline in terms of rainfall and riverine forest ecotype, along a river loop that enlarged ...201020141594
a trk/hkt-type k+ transporter from trypanosoma brucei.the molecular mechanisms of k(+) homeostasis are only poorly understood for protozoan parasites. trypanosoma brucei subsp. parasites, the causative agents of human sleeping sickness and nagana, are strictly extracellular and need to actively concentrate k(+) from their hosts' body fluids. the t. brucei genome contains two putative k(+) channel genes, yet the trypanosomes are insensitive to k(+) antagonists and k(+) channel-blocking agents, and they do not spontaneously depolarize in response to ...201020190075
evidence that low endocytic activity is not directly responsible for human serum resistance in the insect form of african trypanosomes.abstract:201020205710
transcriptome analysis of reproductive tissue and intrauterine developmental stages of the tsetse fly (glossina morsitans morsitans).tsetse flies, vectors of african trypanosomes, undergo viviparous reproduction (the deposition of live offspring). this reproductive strategy results in a large maternal investment and the deposition of a small number of progeny during a female's lifespan. the reproductive biology of tsetse has been studied on a physiological level; however the molecular analysis of tsetse reproduction requires deeper investigation. to build a foundation from which to base molecular studies of tsetse reproductio ...201020214793
tsetse ep protein protects the fly midgut from trypanosome establishment.african trypanosomes undergo a complex developmental process in their tsetse fly vector before transmission back to a vertebrate host. typically, 90% of fly infections fail, most during initial establishment of the parasite in the fly midgut. the specific mechanism(s) underpinning this failure are unknown. we have previously shown that a glossina-specific, immunoresponsive molecule, tsetse ep protein, is up regulated by the fly in response to gram-negative microbial challenge. here we show by kn ...201020221444
d.d.t. and the aeroplane in the control of the tsetse fly and trypanosomiasis in south africa. 194720267547
nutrition of the african in tsetse-fly areas. 194720271152
the maintenance of cattle under conditions of tsetse fly infestation in the field. 194720273229
tsetse fly repellents. 194620286131
tsetse fly control and sleeping sickness in the sudan. 194520293978
repellent properties of delta-octalactone against the tsetse fly, glossina morsitans morsitans.delta-octalactone, produced by several bovidae, has been suggested as a potential repellant of tsetse fly attack. racemic delta-octalactone was synthesized via an abbreviated route. the product was assayed against 3-day old starved teneral female tsetse flies, glossina morsitans morsitans wiedemann (diptera: glossinidae), in a choice wind tunnel and found to be a potent tsetse repellent at doses >or=0.05 mg in 200 microl of paraffin oil (0.05 >p >0.01).200820298116
prospects for the development of odour baits to control the tsetse flies glossina tachinoides and g. palpalis s.l.field studies were done of the responses of glossina palpalis palpalis in côte d'ivoire, and g. p. gambiensis and g. tachinoides in burkina faso, to odours from humans, cattle and pigs. responses were measured either by baiting (1.) biconical traps or (2.) electrocuting black targets with natural host odours. the catch of g. tachinoides from traps was significantly enhanced ( approximately 5x) by odour from cattle but not humans. in contrast, catches from electric targets showed inconsistent res ...201020300513
evaluation of the cost-effectiveness of pyramidal, modified pyramidal and monoscreen traps for the control of the tsetse fly, glossina fuscipes fuscipes, in uganda.several trap designs have been used for sampling and control of the tsetse fly, glossina fuscipes fuscipes, newstead (diptera: glossinidae) based on preferences of individual researchers and program managers with little understanding of the comparative efficiency and cost-effectiveness of trap designs. this study was carried out to evaluate the cost-effectiveness of four commonly used trap designs: monoscreen, modified pyramidal and pyramidal, relative to the standard biconical trap. the study w ...200720345292
identification of a tsetse fly salivary protein with dual inhibitory action on human platelet aggregation.tsetse flies (glossina sp.), the african trypanosome vectors, rely on anti-hemostatic compounds for efficient blood feeding. despite their medical importance, very few salivary proteins have been characterized and functionally annotated.201020351782
nutrient provisioning facilitates homeostasis between tsetse fly (diptera: glossinidae) symbionts.host-associated microbial interactions may involve genome complementation, driving-enhanced communal efficiency and stability. the tsetse fly (diptera: glossinidae), the obligate vector of african trypanosomes (trypanosoma brucei subspp.), harbours two enteric gammaproteobacteria symbionts: wigglesworthia glossinidia and sodalis glossinidius. host coevolution has streamlined the wigglesworthia genome to complement the exclusively sanguivorous tsetse lifestyle. comparative genomics reveal that th ...201020356887
the trypanosoma brucei life cycle switch tbptp1 is structurally conserved and dephosphorylates the nucleolar protein nopp44/46.trypanosoma brucei adapts to changing environments as it cycles through arrested and proliferating stages in the human and tsetse fly hosts. changes in protein tyrosine phosphorylation of several proteins, including nopp44/46, accompany t. brucei development. moreover, inactivation of t. brucei protein-tyrosine phosphatase 1 (tbptp1) triggers differentiation of bloodstream stumpy forms into tsetse procyclic forms through unknown downstream effects. here, we link these events by showing that nopp ...201020444707
sleeping sickness in southeastern uganda: a spatio-temporal analysis of disease risk, 1970-2003.sleeping sickness is a major threat to human health in sub-saharan africa. southeastern uganda has experienced a number of significant epidemics in the past 100 years, most recently from 1976 to 1989. recent and continued spread of the disease has highlighted gaps in the ability of current research to explain and predict the distribution of infection. vegetation cover and changes in vegetation may be important determinants of transmission and disease risk because of the habitat preferences of th ...201020482341
regulation of high-affinity iron acquisition homologues in the tsetse fly symbiont sodalis glossinidius.sodalis glossinidius is a facultative intracellular bacterium that is a secondary symbiont of the tsetse fly (diptera: glossinidae). since studies with other facultative intracellular bacteria have shown that high-affinity iron acquisition genes are upregulated in vivo, we investigated the regulation of several sodalis genes that encode putative iron acquisition systems. these genes, sg1538 (hemt) and sg1516 (sita), are homologous to genes encoding periplasmic heme and iron/manganese transporter ...201020494987
amplified fragment length polymorphism (aflp) analysis of closely related wild and captive tsetse fly (glossina morsitans morsitans) populations.abstract:201020504326
population genetics as a tool to select tsetse control strategies: suppression or eradication of glossina palpalis gambiensis in the niayes of senegal.the government of senegal has initiated the "projet de lutte contre les glossines dans les niayes" to remove the trypanosomosis problem from this area in a sustainable way. due to past failures to sustainably eradicate glossina palpalis gambiensis from the niayes area, controversies remain as to the best strategy implement, i.e. "eradication" versus "suppression." to inform this debate, we used population genetics to measure genetic differentiation between g. palpalis gambiensis from the niayes ...201020520795
tsetse fly blood meal modification and trypanosome identification in two sleeping sickness foci in the forest of southern cameroon.the blood meal origins of 222 tsetse flies (213 glossina palpalis palpalis, 7 glossina pallicera pallicera, one glossina nigrofusca and one glossina caliginea) caught in 2008 in two human african trypanosomiasis foci (bipindi and campo) of south cameroon were investigated. 88.7% of tsetse flies blood meals were identified using the heteroduplex method and the origin of the remaining blood meals (11.3%) was identified by sequencing the cytochrome b gene. most of the meals were from humans (45.9%) ...201020541513
landmarks in the evolution of technologies for identifying trypanosomes in tsetse flies.understanding what the trypanosome pathogens are, their vectors and mode of transmission underpin efforts to control the disease they cause in both humans and livestock. the risk of transmission is estimated by determining what proportion of the vector population is carrying the infectious pathogens. this risk also depends on the infectivity of the trypanosomes to humans and livestock. most livestock pathogens are not infective to humans, whereas the two sub-species that infect humans also infec ...201020542733
a novel phosphatase cascade regulates differentiation in trypanosoma brucei via a glycosomal signaling pathway.in the mammalian bloodstream, the sleeping sickness parasite trypanosoma brucei is held poised for transmission by the activity of a tyrosine phosphatase, tbptp1. this prevents differentiation of the transmissible "stumpy forms" until entry into the tsetse fly, whereupon tbptp1 is inactivated and major changes in parasite physiology are initiated to allow colonization of the arthropod vector. using a substrate-trapping approach, we identified the downstream step in this developmental signaling p ...201020551176
bovine trypanosomosis and its vectors in two districts of bench maji zone, south western ethiopia.a cross-sectional study was carried out from november 2008 to february 2009 in guraferda and sheko districts of bench maji zone, south western ethiopia. the objective of the study was to determine the prevalence of bovine trypanosomosis and the density of its vectors. an overall prevalence of trypanosome infection in the study area was 4.4%. trypanosoma congolense (36.36%) was the dominant trypanosome species followed by trypanosoma vivax (18.18%) and trypanosoma brucei (9.09%). mean packed cell ...201020577803
mobile genetic element proliferation and gene inactivation impact over the genome structure and metabolic capabilities of sodalis glossinidius, the secondary endosymbiont of tsetse flies.genome reduction is a common evolutionary process in symbiotic and pathogenic bacteria. this process has been extensively characterized in bacterial endosymbionts of insects, where primary mutualistic bacteria represent the most extreme cases of genome reduction consequence of a massive process of gene inactivation and loss during their evolution from free-living ancestors. sodalis glossinidius, the secondary endosymbiont of tsetse flies, contains one of the few complete genomes of bacteria at t ...201020649993
a landscape and climate data logistic model of tsetse distribution in kenya.trypanosoma spp, biologically transmitted by the tsetse fly in africa, are a major cause of illness resulting in both high morbidity and mortality among humans, cattle, wild ungulates, and other species. however, tsetse fly distributions change rapidly due to environmental changes, and fine-scale distribution maps are few. due to data scarcity, most presence/absence estimates in kenya prior to 2000 are a combination of local reports, entomological knowledge, and topographic information. the avai ...201020676406
bottlenecks and the maintenance of minor genotypes during the life cycle of trypanosoma brucei.african trypanosomes are digenetic parasites that undergo part of their developmental cycle in mammals and part in tsetse flies. we established a novel technique to monitor the population dynamics of trypanosoma brucei throughout its life cycle while minimising the confounding factors of strain differences or variation in fitness. clones derived from a single trypanosome were tagged with short synthetic dna sequences in a non-transcribed region of the genome. infections were initiated with mixtu ...201020686656
stratified entomological sampling in preparation for an area-wide integrated pest management program: the example of glossina palpalis gambiensis (diptera: glossinidae) in the niayes of senegal.the riverine tsetse species glossina palpalis gambiensis vanderplank 1949 (diptera: glossinidae) inhabits riparian forests along river systems in west africa. the government of senegal has embarked on a project to eliminate this tsetse species, and african animal trypanosomoses, from the niayes area using an area-wide integrated pest management approach. a stratified entomological sampling strategy was therefore developed using spatial analytical tools and mathematical modeling. a preliminary ph ...201020695269
proteomic analysis of glossina pallidipes salivary gland hypertrophy virus virions for immune intervention in tsetse fly colonies.many species of tsetse flies (diptera: glossinidae) can be infected by a virus that causes salivary gland hypertrophy (sgh). the genomes of viruses isolated from glossina pallidipes (gpsghv) and musca domestica (mdsghv) have recently been sequenced. tsetse flies with sgh have reduced fecundity and fertility which cause a serious problem for mass rearing in the frame of sterile insect technique (sit) programmes to control and eradicate tsetse populations in the wild. a potential intervention stra ...201020719992
discovery and verification of osteopontin and beta-2-microglobulin as promising markers for staging human african trypanosomiasis.human african trypanosomiasis, or sleeping sickness, is a parasitic disease endemic in sub-saharan africa, transmitted to humans through the bite of a tsetse fly. the first or hemolymphatic stage of the disease is associated with presence of parasites in the bloodstream, lymphatic system, and body tissues. if patients are left untreated, parasites cross the blood-brain barrier and invade the cerebrospinal fluid and the brain parenchyma, giving rise to the second or meningoencephalitic stage. sta ...201020724469
trypanosomiasis and tsetse fly control. 193320777391
[glossina feeding habits and diversity of species of trypanosomes in an active focus of human african trypanosomiasis in gabon].feeding host is an important factor upon which depend the glossina infection rate and the proportion of different species of trypanosome. glossina feed both upon animals and humans. in order to identify species of trypanosomes present in the komo-mondah focus and to verify whether there is any relationship between the prevalence of sleeping sickness and the feeding habits of glossina, we have carried out an entomological survey in this focus of gabon. flies were dissected and organs were analyse ...201020821180
universal primers for rapid detection of hytrosaviruses.hytrosaviridae is a proposed virus family encompassing viruses that cause salivary gland hypertrophy (sgh) syndrome in infected insects and reduce the fertility in their dipteran insect hosts. they contain a large, double stranded dna genome of 120-190 kbp. to date, these viruses have been detected only in adult diptera. these include hytrosaviruses detected in various tsetse fly species (glossina spp.), the narcissus bulb fly merodon equestris and the house fly musca domestica. the limited numb ...201020923688
incubation of tsetse pupae: increased transmission-rate of trypanosoma rhodesiense in glossina morsitans. 194620984390
the sex ratio of infected flies found in transmission-experiments with glossina morsitans and trypanosoma rhodesiense. 194620984394
salivation by glossina morsitans on to glass slides; a technique for isolating infected flies. 194620997896
an artificially isolated generation of tsetse flies (diptera). 194621000966
human trypanosomiasis and tsetse-flies in liberia. 194621003282
human trypanosomiasis in liberia, 1941-1944. 194621003283
tsetse-flies in liberia; distribution and ecology; possibilities of control. 194621003284
a note on the noise-making ability of the tsetse-fly, glossina palpalis rob.-desv. (diptera, glossinidae), while in flight. 194621022159
the prevalence of african animal trypanosomoses and tsetse presence in western senegal.in 2005, the government of senegal initiated a tsetse eradication campaign in the niayes and la petite côte aiming at the removal of african animal trypanosomosis (aat), which is one of the main constraints to the development of more effective cattle production systems. the target area has particular meteorological and ecological characteristics that provide great potential for animal production, but it is unfortunately still infested by the riverine tsetse species glossina palpalis gambiensis v ...201021073148
theoretical levels of control as a function of mean temperature and spray efficacy in the aerial spraying of tsetse fly.the hypothetical impact of aerial spraying on tsetse fly populations is investigated. spray cycles are scheduled at intervals two days short of the first interlarval period and halted once the last of the female flies that originated from pre-spray-deposited pupae have been sprayed twice. the effect of temperature on the aerial spraying of tsetse, through its reproductive cycle and general population dynamics, is of particular interest, given that cooler weather is preferred for the settling of ...201021087595
fine structure of the female reproductive system in a viviparous insect, glossina morsitans morsitans (diptera, glossinidae).the female reproductive system of the tsetse fly glossina morsitans morsitans is analysed by scanning electron microscopy (sem). the study focuses in particular on the choriothete, a peculiar uterine structure involved in the viviparous mode of reproduction of glossina morsitans morsitans. under light microscopy, the choriothete appears formed by numerous tongue-like folds projecting towards the uterine lumen and lined by a thin cuticle. sem analysis highlights for the first time a distinctive n ...201021094964
tsetse fly control and trypanosomiasis in africa, quo vadis?national and international efforts to eradicate tsetse fly-borne human and animal trypanosomiasis are critically evaluated, and possible reasons for their failure in many cases are discussed. some formerly performed campaigns in specific areas with positive results cannot be taken as examples to solve the main problems. in future, a significant reduction of trypanosomiasis cases will be possible to achieve only if a concerted long-term pan-african approach, based on financial security, the conti ...201021104211
effect of host pregnancy on pupal production by the tsetse fly. 196621108521
functional analysis of the twin-arginine translocation pathway in sodalis glossinidius, a bacterial symbiont of the tsetse fly.this study demonstrates a functional twin-arginine (tat) translocation pathway present in the tsetse fly symbiont sodalis glossinidius and its potential to export active heterologous proteins to the periplasm. functionality was demonstrated using green fluorescent protein (gfp) fused to the tat signal peptide of escherichia coli trimethylamine n-oxide reductase (tora).201021148698
molecular bases of cytoskeleton plasticity during the trypanosoma brucei parasite cycle.african trypanosomes are flagellated protozoan parasites responsible for sleeping sickness and transmitted by tsetse flies. the accomplishment of their parasite cycle requires adaptation to highly diverse environments. these transitions take place in a strictly defined order and are accompanied by spectacular morphological modifications in cell size, shape and positioning of organelles. to understand the molecular bases of these processes, parasites isolated from different tissues of the tsetse ...201121159115
a new transmission risk index for human african trypanosomiasis and its application in the identification of sites of high transmission of sleeping sickness in the fontem focus of southwest cameroon.a new index for the risk for transmission of human african trypanosomiasis was developed from an earlier index by adding terms for the proportion of tsetse infected with trypanosoma brucei gambiense group 1 and the contribution of animals to tsetse diet. the validity of the new index was then assessed in the fontem focus of southwest cameroon. averages of 0.66 and 4.85 glossina palpalis palpalis (diptera: glossinidae) were caught per trap/day at the end of one rainy season (november) and the sta ...201021198712
spatio-temporal distribution of tsetse and other biting flies in the mouhoun river basin, burkina faso.in the mouhoun river basin, burkina faso, the main vectors of african animal trypanosomoses are glossina palpalis gambiensis vanderplank and glossina tachinoides westwood (diptera: glossinidae), both of which are riverine tsetse species. the aim of our study was to understand the impact of landscape anthropogenic changes on the seasonal dynamics of vectors and associated trypanosomosis risk. three sites were selected on the basis of the level of disturbance of tsetse habitats and predominant tse ...201021198714
tbunc119 and its binding protein complex are essential for propagation, motility, and morphogenesis of trypanosoma brucei procyclic form cells.flagellum-mediated motility of trypanosoma brucei is considered to be essential for the parasite to complete stage development in the tsetse fly vector, while the mechanism by which flagellum-mediated motility is controlled are not fully understood. we thus compared t. brucei whole gene products (amino acid sequence) with caenorhabditis elegans unc (uncoordinated) proteins, in order to find uncharacterized motility-related t. brucei genes. through in silico analysis, we found 88 gene products wh ...201021203515
the tsetse fly glossina fuscipes fuscipes (diptera: glossina) harbours a surprising diversity of bacteria other than symbionts.three different bacterial species are regularly described from tsetse flies. however, no broad screens have been performed to investigate the existence of other bacteria in this medically and agriculturally important vector insect. utilising both culture dependent and independent methods we show that kenyan populations of glossina fuscipes fuscipes harbour a surprising diversity of bacteria. bacteria were isolated from 72% of flies with 23 different bacterial species identified. the firmicutes p ...201121203841
disappearance of some human african trypanosomiasis transmission foci in zambia in the absence of a tsetse fly and trypanosomiasis control program over a period of forty years.we conducted a situation analysis of human african trypanosomiasis (hat) in zambia from january 2000 to april 2007. the aim of this survey was to identify districts in zambia that were still recording cases of hat. three districts namely, mpika, chama, and chipata were found to be still reporting cases of hat and thus lay in hat transmission foci in north eastern zambia. during the period under review, 24 cases of hat were reported from these three districts. we thereafter reviewed literature on ...201121276598
progress towards the eradication of tsetse from the loos islands, guinea.the tsetse fly glossina palpalis gambiensis is the main vector of sleeping sickness (human african trypanosomiasis - hat) in west africa, in particular in littoral guinea where this disease is currently very active. the loos islands constitute a small archipelago some 5 km from mainland guinea, where g. p. gambiensis is well known as a nuisance and potential disease vector by inhabitants of the three main islands, fotoba, room, and kassa. the national control program against hat of guinea has de ...201121310074
identification of the meiotic life cycle stage of trypanosoma brucei in the tsetse fly.elucidating the mechanism of genetic exchange is fundamental for understanding how genes for such traits as virulence, disease phenotype, and drug resistance are transferred between pathogen strains. genetic exchange occurs in the parasitic protists trypanosoma brucei, t. cruzi, and leishmania major, but the precise cellular mechanisms are unknown, because the process has not been observed directly. here we exploit the identification of homologs of meiotic genes in the t. brucei genome and demon ...201121321215
microsatellite genotyping reveals diversity within populations of sodalis glossinidius, the secondary symbiont of tsetse flies.the aim of this study was to develop a pcr-based microsatellite genotyping method for identifying genetic diversity in sodalis glossinidius, a symbiont associated with tsetse fly infection by trypanosomes causing human and animal trypanosomiasis. allelic polymorphism at three loci, investigated on 40 fly gut extracts, evidenced eight alleles and the existence of five genotypes. this novel approach was shown to be efficient and suitable for routine large-scale genotyping of s. glossinidius presen ...201121334833
population vulnerability and disability in kenya's tsetse fly habitats.human african trypanosomiasis (hat), also referred to as sleeping sickness, and african animal trypanosomaisis (aat), known as nagana, are highly prevalent parasitic vector-borne diseases in sub-saharan africa. humans acquire trypanosomiasis following the bite of a tsetse fly infected with the protozoa trypanosoma brucei (t.b.) spp. -i.e., t.b. gambiense in west and central africa and t.b. rhodesiense in east and southern africa. over the last decade hat diagnostic capacity to estimate hat preva ...201121347453
the trypanosoma brucei zinc finger protein zc3h18 is involved in differentiation.in mammalian cells, the degradation of mrnas that have au-rich elements in their 3'-untranslated regions is accelerated by the binding of proteins that contain two ccch-zinc-finger-domains. three ccch zinc-finger proteins, tbzfp1, tbzfp2, and tbzfp3, have been shown to have roles in trypanosome differentiation. we here studied another protein, zc3h18, which has two ccch zinc finger domains. the zc3h18 gene is not essential in bloodstream forms, but in an in vitro model of differentiation, deplet ...201121354218
trypanosoma brucei s.l.: microsatellite markers revealed high level of multiple genotypes in the mid-guts of wild tsetse flies of the fontem sleeping sickness focus of cameroon.to identify trypanosoma brucei genotypes which are potentially transmitted in a sleeping sickness focus, microsatellite markers were used to characterize t. brucei found in the mid-guts of wild tsetse flies of the fontem sleeping sickness focus in cameroon. for this study, two entomological surveys were performed during which 2685 tsetse flies were collected and 1596 (59.2%) were dissected. microscopic examination revealed 1.19% (19/1596) mid-gut infections with trypanosomes; the pcr method iden ...201121376044
tracking the feeding patterns of tsetse flies (glossina genus) by analysis of bloodmeals using mitochondrial cytochromes genes.tsetse flies are notoriously difficult to observe in nature, particularly when populations densities are low. it is therefore difficult to observe them on their hosts in nature; hence their vertebrate species can very often only be determined indirectly by analysis of their gut contents. this knowledge is a critical component of the information on which control tactics can be developed. the objective of this study was to determine the sources of tsetse bloodmeals, hence investigate their feeding ...201121386971
bacterial diversity associated with populations of glossina spp. from cameroon and distribution within the campo sleeping sickness focus.tsetse flies were sampled in three villages of the campo sleeping sickness focus in south cameroon. the aim of this study was to investigate the flies' gut bacterial composition using culture-dependent techniques. out of the 32 flies analyzed (27 glossina palpalis palpalis, two glossina pallicera, one glossina nigrofusca, and two glossina caliginea), 17 were shown to be inhabited by diverse bacteria belonging to the proteobacteria, the firmicutes, or the bacteroidetes phyla. phylogenetic analysi ...201121387098
a general model for mortality in adult tsetse (glossina spp.).tsetse exhibit a u-shaped age-mortality curve, with high losses after eclosion and a well-marked ageing process, which is particularly dramatic in males. a three-parameter (k(1) -k(3) ) model for age-dependent adult instantaneous mortality rates was constructed using mark-recapture data for the tsetse fly glossina morsitans morsitans westwood (diptera: glossinidae). mortality changed linearly with k(1) over all ages; k(2) affected only losses in roughly the first week of adult life, and k(3) con ...201121414021
antimicrobial peptide killing of african trypanosomes.the diseases caused by trypanosomes are medically and economically devastating to the population of sub-saharan africa. parasites of the genus trypanosoma, infect both humans, causing african sleeping sickness, and livestock, causing nagana. the development of effective treatment strategies has suffered from the severe side effects of approved drugs, resistance and major difficulties in delivering drugs. antimicrobial peptides are ubiquitous components of immune defense and are being rigorously ...201121517904
[ivory coast uprising and returning burkinabe immigrants: evaluation of the risk for reemergence of sleeping sickness in burkina faso].following the sociopolitical unrest that occurred in ivory coast in 2002, 360,000 burkinabe immigrants returned to burkina faso that was the epicenter of sleeping sickness last century and is now thought to be free of autochthonous transmission. the purpose of this study was to determine if the massive return of immigrants from human african trypanosomiasis (hat) endemic areas of ivory coast to areas in burkina faso where the vector (tsetse fly) is currently present could lead to re-emergence of ...201021520653
have tsetse flies disappeared from brazzaville town?from 1980 to 1985, the zoological park of brazzaville was the only tsetse resting site located in downtown which supplied others temporary sites. the last trapping survey carried out in this area in 1987 showed that there were no more tsetse flies. knowing that areas free of tsetse used to be reinvaded many years later, we have carried out an entomological survey in the area with the aim to verify what has happened more than twenty years later; given that suitable environmental conditions for gl ...200921532712
bovine trypanosomosis in the upper west region of ghana: entomological, parasitological and serological cross-sectional surveys.baseline surveys were conducted in the upper west region of ghana to assess the distribution and densities of tsetse species, as well as the prevalence of bovine trypanosomosis. the entomological survey was designed to cover the suitable tsetse habitats along the three main rivers in the study area (i.e. black volta, kulpawn and sissili). results indicated the presence of glossina tachinoides in all three river basins, whilst glossina palpalis gambiensis was only found close to the southern limi ...201121550616
polymorphic microsatellite markers for the tsetse fly glossina fuscipes fuscipes (diptera: glossinidae), a vector of human african trypanosomiasis.our understanding of glossina fuscipes fuscipes, a major vector of sleeping sickness, has been severely constrained by a lack of genetic markers for mapping and population genetic studies. here we present 10 newly developed microsatellite loci for this tsetse species. heterozygosity levels in moyo, an ugandan population, averaged 0.57, with only two loci showing very low heterozygosity. five loci carried more than six alleles. together with five recently published microsatellite loci, this bring ...200821586090
tsetse immune system maturation requires the presence of obligate symbionts in larvae.beneficial microbial symbionts serve important functions within their hosts, including dietary supplementation and maintenance of immune system homeostasis. little is known about the mechanisms that enable these bacteria to induce specific host phenotypes during development and into adulthood. here we used the tsetse fly, glossina morsitans, and its obligate mutualist, wigglesworthia glossinidia, to investigate the co-evolutionary adaptations that influence the development of host physiological ...201121655301
polyandry is a common event in wild populations of the tsetse fly glossina fuscipes fuscipes and may impact population reduction measures.glossina fuscipes fuscipes is the main vector of human and animal trypanosomiasis in africa, particularly in uganda. attempts to control/eradicate this species using biological methods require knowledge of its reproductive biology. an important aspect is the number of times a female mates in the wild as this influences the effective population size and may constitute a critical factor in determining the success of control methods. to date, polyandry in g.f. fuscipes has not been investigated in ...201121666797
population genetics of trypanosoma evansi from camel in the sudan.genetic variation of microsatellite loci is a widely used method for the analysis of population genetic structure of microorganisms. we have investigated genetic variation at 15 microsatellite loci of t. evansi isolated from camels in sudan and kenya to evaluate the genetic information partitioned within and between individuals and between sites. we detected a strong signal of isolation by distance across the area sampled. the results also indicate that either, and as expected, t. evansi is pure ...201121666799
trapping tsetse flies on water.riverine tsetse flies such as glossina palpalis gambiensis and g. tachinoides are the vectors of human and animal trypanosomoses in west africa. despite intimate links between tsetse and water, to our knowledge there has never been any attempt to design trapping devices that would catch tsetse on water. in mangrove (guinea) one challenging issue is the tide, because height above the ground for a trap is a key factor affecting tsetse catches. the trap was mounted on the remains of an old wooden d ...201121678789
impact of microscopic motility on the swimming behavior of parasites: straighter trypanosomes are more directional.microorganisms, particularly parasites, have developed sophisticated swimming mechanisms to cope with a varied range of environments. african trypanosomes, causative agents of fatal illness in humans and animals, use an insect vector (the tsetse fly) to infect mammals, involving many developmental changes in which cell motility is of prime importance. our studies reveal that differences in cell body shape are correlated with a diverse range of cell behaviors contributing to the directional motio ...201121698122
sleeping sickness.human african trypanosomiasis (hat), or sleeping sickness, is a vector-borne disease that flourishes in impoverished, rural parts of sub-saharan africa. it is caused by infection with the protozoan parasite trypanosoma brucei and is transmitted by tsetse flies of the genus glossina. the majority of cases are caused by t. b. gambiense, which gives rise to the chronic, anthroponotic endemic disease in western and central africa. infection with t. b. rhodesiense leads to the acute, zoonotic form of ...201121722252
Contrasting population structures of two vectors of African trypanosomoses in Burkina Faso: consequences for control.African animal trypanosomosis is a major obstacle to the development of more efficient and sustainable livestock production systems in West Africa. Riverine tsetse species such as Glossina palpalis gambiensis Vanderplank and Glossina tachinoides Westwood are the major vectors. A wide variety of control tactics is available to manage these vectors, but their removal will in most cases only be sustainable if the control effort is targeting an entire tsetse population within a circumscribed area.201121738812
population genetics of glossina palpalis palpalis from central african sleeping sickness foci.abstract: background: glossina palpalis palpalis (diptera: glossinidae) is widespread in west africa, and is the main vector of sleeping sickness in cameroon as well as in the bas congo province of the democratic republic of congo. however, little is known on the structure of its populations. we investigated g. p. palpalis population genetic structure in five sleeping sickness foci (four in cameroon, one in democratic republic of congo) using eight microsatellite dna markers. results: a strong i ...201121767402
how do tsetse recognise their hosts? the role of shape in the responses of tsetse (glossina fuscipes and g. palpalis) to artificial hosts.palpalis-group tsetse, particularly the subspecies of glossina palpalis and g. fuscipes, are the most important transmitters of human african trypanomiasis (hat), transmitting >95% of cases. traps and insecticide-treated targets are used to control tsetse but more cost-effective baits might be developed through a better understanding of the fly's host-seeking behaviour. electrocuting grids were used to assess the numbers of g. palpalis palpalis and g. fuscipes quanzensis attracted to and landing ...201121829734
Cryptic diversity within the major trypanosomiasis vector Glossina fuscipes revealed by molecular markers.The tsetse fly Glossina fuscipes s.l. is responsible for the transmission of approximately 90% of cases of human African trypanosomiasis (HAT) or sleeping sickness. Three G. fuscipes subspecies have been described, primarily based upon subtle differences in the morphology of their genitalia. Here we describe a study conducted across the range of this important vector to determine whether molecular evidence generated from nuclear DNA (microsatellites and gene sequence information), mitochondrial ...201121858237
lipophorin acts as a shuttle of lipids to the milk gland during tsetse fly pregnancy.during pregnancy in the viviparous tsetse fly, lipid mobilization is essential for the production of milk to feed the developing intrauterine larva. lipophorin (lp) functions as the major lipid transport protein in insects and closely-related arthropods. in this study, we assessed the role of lp and the lipophorin receptor (lpr) in the lipid mobilization process during tsetse reproduction. we identified single gene sequences for gmmlp and gmmlpr from the genome of glossinamorsitansmorsitans, and ...201121875592
genetic diversity and population structure of the secondary symbiont of tsetse flies, sodalis glossinidius, in sleeping sickness foci in cameroon.previous studies have shown substantial differences in sodalis glossinidius and trypanosome infection rates between glossina palpalis palpalis populations from two cameroonian foci of human african trypanosomiasis (hat), bipindi and campo. we hypothesized that the geographical isolation of the two foci may have induced independent evolution in the two areas, resulting in the diversification of symbiont genotypes.201121886849
Human African trypanosomiasis in endemic populations and travellers.Human African trypanosomiasis (HAT) or sleeping sickness is caused by the protozoan parasites Trypanosoma brucei (T.b.) gambiense (West African form) and T.b. rhodesiense (East African form) that are transmitted by the bite of the tsetse fly, Glossina spp.. Whereas most patients in endemic populations are infected with T.b. gambiense, most tourists are infected with T.b. rhodesiense. In endemic populations, T.b. gambiense HAT is characterized by chronic and intermittent fever, headache, pruritus ...201121901632
towards an optimal design of target for tsetse control: comparisons of novel targets for the control of palpalis group tsetse in west africa.tsetse flies of the palpalis group are the main vectors of sleeping sickness in africa. insecticide impregnated targets are one of the most effective tools for control. however, the cost of these devices still represents a constraint to their wider use. the objective was therefore to improve the cost effectiveness of currently used devices.201121949896
the chemistry and biology of trypanosomal trans-sialidases: virulence factors in chagas disease and sleeping sickness.trans-sialidases constitute a special group of the sialidase family. they occur in some trypanosome species and, in a unique reversible reaction, transfer sialic acids from one glycosidic linkage with galactose (donor) to another galactose (acceptor), to form (α2-3)-sialyl linkages. trypanosomes cause such devastating human diseases as chagas disease in south america (trypanosoma cruzi) or sleeping sickness in africa (trypanosoma brucei). the trans-sialidases strongly contribute to the pathogeni ...201121956798
alba proteins are stage regulated during trypanosome development in the tsetse fly and participate in differentiation.the protozoan parasite trypanosoma brucei is responsible for sleeping sickness and alternates between mammal and tsetse fly hosts, where it has to adapt to different environments. we investigated the role of two members of the alba family, which encodes hypothetical rna-binding proteins conserved in most eukaryotes. we show that alba3/4 proteins colocalize with the dhh1 rna-binding protein and with a subset of poly(a+) rna in stress granules upon starvation. depletion of alba3/4 proteins by rna ...201121965287
native microbiota shape insect vector competence for human pathogens.the resident microbiota of insect vectors can impede transmission of human pathogens. recent studies have highlighted the capacity of endogenous bacteria to decrease viral and parasitic infections in mosquito and tsetse fly vectors by activating their immune responses or directly inhibiting pathogen development. these microbes may prove effective agents for manipulating the vector competence of malaria and other important human pathogens.201122018231
attenuation of the sensing capabilities of phoq in transition to obligate insect-bacterial association.sodalis glossinidius, a maternally inherited endosymbiont of the tsetse fly, maintains genes encoding homologues of the phop-phoq two-component regulatory system. this two-component system has been extensively studied in facultative bacterial pathogens and is known to serve as an environmental magnesium sensor and a regulator of key virulence determinants. in the current study, we show that the inactivation of the response regulator, phop, renders s. glossinidius sensitive to insect derived cati ...201122072980
expression of chemosensory proteins in the tsetse fly glossina morsitans morsitans is related to female host-seeking behaviour.chemosensory proteins (csps) are a class of soluble proteins present in high concentrations in the sensilla of insect antennae. it has been proposed that they play an important role in insect olfaction by mediating interactions between odorants and odorant receptors. here we report, for the first time, the presence of five csp genes in the tsetse fly glossina morsitans morsitans, a major vector transmitting nagana in livestock. real-time quantitative reverse transcription pcr showed that three o ...201122074189
post eclosion age predicts the prevalence of midgut trypanosome infections in glossina.the teneral phenomenon, as observed in glossina sp., refers to the increased susceptibility of the fly to trypanosome infection when the first bloodmeal taken is trypanosome-infected. in recent years, the term teneral has gradually become synonymous with unfed, and thus fails to consider the age of the newly emerged fly at the time the first bloodmeal is taken. furthermore, conflicting evidence exists of the effect of the age of the teneral fly post eclosion when it is given the infected first b ...201122087240
Glycolysis in the african trypanosome: targeting enzymes and their subcellular compartments for therapeutic development.Subspecies of the African trypanosome, Trypanosoma brucei, which cause human African trypanosomiasis, are transmitted by the tsetse fly, with transmission-essential lifecycle stages occurring in both the insect vector and human host. During infection of the human host, the parasite is limited to using glycolysis of host sugar for ATP production. This dependence on glucose breakdown presents a series of targets for potential therapeutic development, many of which have been explored and validated ...201122091393
[Entomological survey in the historical sleeping sickness focus of Bendje (Gabon)].The situation of human African trypanosomiasis (sleeping sickness) is poorly known in Gabon. Most of the historical foci have not been investigated for more than 15 years. Few cases are passively recorded from the historical focus of Bendjé; they involved mainly fishermen but determining their contamination site is difficult because of their mobility due to their activity. The presence of these cases in that focus could favour its reactivation if the vector is still there. In order to assess a p ...201122091460
Multiple Trypanosoma infections are common amongst Glossina species in the new farming areas of Rufiji district, Tanzania.ABSTRACT: BACKGROUND: Tsetse flies and trypanosomiasis are among several factors that constrain livestock development in Tanzania. Over the years Rufiji District was excluded from livestock production owing to tsetse fly infestation, however, a few years ago there was an influx of livestock following evictions aimed at conserving the Usangu wetlands. METHODS: A study was conducted to determine the efficiency of available traps for catching tsetse flies, Glossina species infesting the area, thei ...201122093363
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