| effects of combining the fungi beauveria bassiana and metarhizium anisopliae on the mortality of the tick amblyomma variegatum (ixodidae) in relation to seasonal changes. | the effect of formulation, fungal concentration, type and seasonal changes on the mortality of the tick amblyomma variegatum was investigated. a previous study demonstrated high pathogenicity of strains of the fungi beauveria bassiana and metarhizium anisopliae against the ticks rhipicephalus appendiculatus and amblyomma variegatum (kaaya et al. j invertebr pathol 1996; 67: 15-20). the present study was undertaken to explore possible additive or synergistic effects of the two fungi on a. variega ... | 2005 | 15983739 |
| transcription analysis of the major antigenic protein 1 multigene family of three in vitro-cultured ehrlichia ruminantium isolates. | ehrlichia ruminantium, an obligate intracellular bacterium transmitted by ticks of the genus amblyomma, causes heartwater disease in ruminants. the gene coding for the major antigenic protein map1 is part of a multigene family consisting of a cluster containing 16 paralogs. in the search for differentially regulated genes between e. ruminantium grown in endothelial and tick cell lines that could be used in vaccine development and to determine if differences in the map1 gene cluster exist between ... | 2005 | 15995193 |
| identification of candidate sialome components expressed in ixodid tick salivary glands using secretion signal complementation in mammalian cells. | ixodid ticks manipulate mammalian host pathways by secreting molecules from salivary glands. novel cdnas containing functional secretion signals were isolated from ixodid tick salivary glands using a signal sequence trap. only 15/61 rhipicephalus appendiculatus and 1/7 amblyomma variegatum cdnas had significant identity (< 1e-15) to previously identified sequences. polypeptides that may interact with host pathways included a kinase inhibitor. two proteins encoded homologues of the yolk protein v ... | 2005 | 16033433 |
| tick-borne rickettsioses around the world: emerging diseases challenging old concepts. | during most of the 20th century, the epidemiology of tick-borne rickettsioses could be summarized as the occurrence of a single pathogenic rickettsia on each continent. an element of this paradigm suggested that the many other characterized and noncharacterized rickettsiae isolated from ticks were not pathogenic to humans. in this context, it was considered that relatively few tick-borne rickettsiae caused human disease. this concept was modified extensively from 1984 through 2005 by the identif ... | 2005 | 16223955 |
| rodent malaria parasites plasmodium chabaudi and p. vinckei do not increase their rates of gametocytogenesis in response to mosquito probing. | several vector-borne infectious agents facultatively alter their life history strategies in response to local vector densities. some evidence suggests that malaria parasites invest more heavily in transmission stage production (gametocytogenesis) when vectors are present. such a strategy could rapidly increase malaria transmission rates, particularly when adult mosquitoes begin to appear after dry seasons. however, in contrast to a recent experiment with a rodent malaria (plasmodium chabaudi), w ... | 2005 | 16243686 |
| detection of babesia caballi in amblyomma variegatum ticks (acari: ixodidae) collected from cattle in the republic of guinea. | a reverse line blot hybridisation (rlb) assay was applied to screen amblyomma variegatum adult ticks (n = 504) collected from n'dama cattle in the republic of guinea. in a pcr, the v1 hypervariable region of the 16s ribosomal rna (rrna) gene was amplified with a set of primers unique for species of the genera anaplasma and ehrlichia, and the v4 hypervariable region of the 18s rrna gene was amplified with primers specific for members of the genera theileria and babesia. amplified pcr products fro ... | 2005 | 16252481 |
| human skin lesions in east central state, nigeria due to the larvae of amblyomma variegatum (fabricius, 1794). | | 1973 | 16366347 |
| ehrlichia ruminantium, sudan. | | 2005 | 16422005 |
| rickettsia africae in the west indies. | rickettsia africae is the agent of african tick-bite fever, a mild but common disease of local persons and tourists in africa. the major vector of this spotted fever group rickettsia is most likely amblyomma variegatum, the tropical bont tick, which has become widely distributed through the west indies in the last 30 years. this report reviews all available information on r. africae in the west indies. | 2006 | 16494746 |
| comparative genomic analysis of three strains of ehrlichia ruminantium reveals an active process of genome size plasticity. | ehrlichia ruminantium is the causative agent of heartwater, a major tick-borne disease of livestock in africa that has been introduced in the caribbean and is threatening to emerge and spread on the american mainland. we sequenced the complete genomes of two strains of e. ruminantium of differing phenotypes, strains gardel (erga; 1,499,920 bp), from the island of guadeloupe, and welgevonden (erwe; 1,512,977 bp), originating in south africa and maintained in guadeloupe in a different cell environ ... | 2006 | 16547041 |
| performance of a prototype baited-trap in attracting and infecting the tick amblyomma variegatum (acari: ixodidae) in field experiments. | investigations were commenced to study the potential use of the fungi, beauveria bassiana, metarhizium anisopliae, and the attraction-aggregation-attachment pheromone (aaap) for the control of ambloyomma variegatum as an environmentally friendly technology. the objective of the study was to develop and test a device, which could be used for pheromone and carbon dioxide delivery and infection of ticks with the fungi in an attempt to control the tick populations in the vegetation. using a pheromon ... | 2006 | 16596354 |
| successful and currently ongoing parasite eradication programs. | the eradication of parasitic diseases is not a new concept. the most successful programs of parasite eradication have occurred with species of veterinary importance. the first such program, the eradication of texas cattle fever from the united states, is one of the great success stories of disease eradication. the american screwworm eradication program is ongoing and is serving as a guiding impetus for many of the ongoing or proposed vector eradication schemes around the world. the success of th ... | 2006 | 16730411 |
| tickborne arbovirus surveillance in market livestock, nairobi, kenya. | to identify tickborne viruses circulating in kenya and the surrounding region, we conducted surveillance at abattoirs in nairobi, kenya. species of ticks collected included rhipicephalus pulchellus (56%), amblyomma gemma (14%), r. appendiculatus (8%), a. variegatum (6%), and others. a total of 56 virus isolates were obtained, 26 from a. gemma, 17 from r. pulchellus, 6 from a. variegatum, and 7 from other species. virus isolates included dugbe virus (dugv), an unknown virus related to dugv, thogo ... | 2006 | 16836823 |
| genetic structure and evolution of the vps25 family, a yeast escrt-ii component. | vps25p is the product of yeast gene vps25 and is found in an endosomal sorting complex required for transport (escrt)-ii, along with vps22p and vps36p. this complex is essential for sorting of ubiquitinated biosynthetic and endosomal cargoes into endosomes. | 2006 | 16889659 |
| attachment kinetics of the adult tick amblyomma variegatum to cattle. | at the beginning of the 1999 rainy season, three traditional cattle herds were monitored for 48 days while grazing in the bushy savannah of southwestern burkina faso. cattle in each herd were caught on several occasions each day and the attached ticks were counted. this confirmed that amblyomma variegatum fabricius (acari: ixodidae) adults picked up in the pastures mainly attach to the interdigital areas (87% of the 791 ticks captured), and reach the predilection sites later (chest and udder/ing ... | 2006 | 17044883 |
| new member of the protein disulfide isomerase (pdi) family identified in amblyomma variegatum tick. | ticks belonging to arthropoda are blood feeding, geographically widespread ectoparasites of mammals, reptiles and birds. their saliva contains active substances that protect them from host immune attack and allow for transmission of various pathogens during the feeding process. characterization of tick saliva components can therefore contribute to the development of effective methods for the control of tick-borne diseases. here we describe the identification and basic characterization of a gene ... | 2006 | 17098169 |
| catalytic advantages provided by selenocysteine in methionine-s-sulfoxide reductases. | methionine sulfoxide reductases are key enzymes that repair oxidatively damaged proteins. two distinct stereospecific enzyme families are responsible for this function: msra (methionine-s-sulfoxide reductase) and msrb (methionine-r-sulfoxide reductase). in the present study, we identified multiple selenoprotein msra sequences in organisms from bacteria to animals. we characterized the selenocysteine (sec)-containing chlamydomonas msra and found that this protein exhibited 10-50-fold higher activ ... | 2006 | 17105189 |
| malaria parasite growth is stimulated by mosquito probing. | the ability of malaria parasites to respond positively to the presence of feeding mosquito vectors would clearly be advantageous to transmission. in this study, anopheles stephensi mosquitoes probed mice infected with the rodent malaria parasite, plasmodium chabaudi. growth of asexual stages was accelerated and gametocytes appeared 1-2 days earlier than in controls. this first study, to our knowledge, of the effects of mosquitoes on 'in-host' growth and development of plasmodium has profound imp ... | 2005 | 17148162 |
| gene silencing of the tick protective antigens, bm86, bm91 and subolesin, in the one-host tick boophilus microplus by rna interference. | the use of rna interference (rnai) to assess gene function has been demonstrated in several three-host tick species but adaptation of rnai to the one-host tick, boophilus microplus, has not been reported. we evaluated the application of rnai in b. microplus and the effect of gene silencing on three tick-protective antigens: bm86, bm91 and subolesin. gene-specific double-stranded (dsrna) was injected into two tick stages, freshly molted unfed and engorged females, and specific gene silencing was ... | 2007 | 17196597 |
| footbath acaricide treatment to control cattle infestation by the tick amblyomma variegatum. | previous studies have shown that about 90% of adult amblyomma variegatum fabricius (acari: ixodidae) picked up daily by grazing cattle are still attached to the interdigital areas in the evening, when the animals return from pasture. it was therefore postulated that a targeted treatment, designed to kill the ticks attached to the feet, would limit infestation of the predilection sites. footbaths filled with various pyrethroid formulations were used over 3 years, at the beginning of the rainy sea ... | 2006 | 17199752 |
| [insects know no border.]. | one of the major consequences of the joined action of demographic pressure and evolution of human activities lies in enormous increase of transportation, both in frequence and speed; taking advantage of these facilities, some arthropods could increase their geographical distribution and create new health threats. several demonstrative examples are exposed in order to illustrate this anthropic dissemination of the vectors : the introduction of anopheles gambiae s.l. in mauritius island between 18 ... | 1996 | 17292311 |
| differential transcription of the major antigenic protein 1 multigene family of ehrlichia ruminantium in amblyomma variegatum ticks. | the rickettsial pathogen ehrlichia ruminantium causes heartwater in ruminants and is transmitted by ticks of the genus amblyomma. the map1 gene, encoding the major surface protein map1, is a member of a multigene family containing 16 paralogs. in order to investigate differential transcription of genes of the map1 multigene family in vivo in unfed and feeding ticks, rna was extracted from midguts and salivary glands of e. ruminantium-infected adult female amblyomma variegatum ticks and analysed ... | 2007 | 17321077 |
| using invaded range data to model the climate suitability for amblyomma variegatum (acari: ixodidae) in the new world. | climate matching models are in increasing use to predict distributions of living organisms, using records of the known distribution of a species to map its expected range of habitat suitability. here, we modelled the known distribution of the tick amblyomma variegatum in africa as a preliminary step to delineate the most probable range of climatically suitable habitat for the tick in the new world. we used two presence-only methods (one based in the gower distance, the other based on the maximum ... | 2007 | 17347921 |
| differential anti-chemokine activity of amblyomma variegatum adult ticks during blood-feeding. | ticks secrete a cocktail of immunomodulatory molecules in their saliva during blood-feeding, including chemokine-binding factors that help control the activity of host immunocompetent cells. here we demonstrate differential dynamics of anti il-8 (cxcl8), mcp-1 (ccl2), mip-1 (ccl3), rantes (ccl5) and eotaxin (ccl11) activities in salivary gland extracts of adult amblyomma variegatum. unfed male and female ticks showed activity against all the chemokines except ccl5; anti-ccl11 activity was partic ... | 2007 | 17371454 |
| olfactory receptors on the maxillary palps of small ermine moth larvae: evolutionary history of benzaldehyde sensitivity. | in lepidopterous larvae the maxillary palps contain a large portion of the sensory equipment of the insect. yet, knowledge about the sensitivity of these cells is limited. in this paper a morphological, behavioral, and electrophysiological investigation of the maxillary palps of yponomeuta cagnagellus (lepidoptera: yponomeutidae) is presented. in addition to thermoreceptors, co(2) receptors, and gustatory receptors, evidence is reported for the existence of two groups of receptor cells sensitive ... | 2007 | 17372741 |
| poor inheritance of low attractiveness for amblyomma variegatum in cattle. | because of the high variability of cattle infestation, selective breeding has been proposed to control three-host ticks in africa in the same way as it has been implemented to control the one-host tick boophilus microplus in australia. interbreeding (divergent selection experiment) between gudali zebu cattle was performed at the wakwa research centre, adamawa, cameroon to assess the feasibility and impact of such a selective breeding programme. fifty cows (chosen out of 129) and 2 bulls (chosen ... | 2007 | 17418491 |
| molecular detection of ehrlichia ruminantium infection in amblyomma variegatum ticks in the gambia. | in west africa, losses due to heartwater disease are not known because the incidence/prevalence has not been well studied or documented. to develop a diagnostic tool for molecular epidemiology, three pcr-based diagnostic assays, a nested pcs20 pcr, a nested map1 pcr and a nested reverse line blot (rlb) hybridization assay, were evaluated to determine their ability to detect infection in vector ticks, by applying them simultaneously to a. variegatum field ticks to detect ehrlichia ruminantium, th ... | 2007 | 17476576 |
| tick-borne flavivirus infection in ixodes scapularis larvae: development of a novel method for synchronous viral infection of ticks. | following a bite from an infected tick, tick-borne flaviviruses cause encephalitis, meningitis and hemorrhagic fever in humans. although these viruses spend most of their time in the tick, little is known regarding the virus-vector interactions. we developed a simple method for synchronously infecting ixodes scapularis larvae with langat virus (lgtv) by immersion in media containing the virus. this technique resulted in approximately 96% of ticks becoming infected. lgtv infection and replication ... | 2007 | 17490700 |
| genetic diversity of ehrlichia ruminantium in amblyomma variegatum ticks and small ruminants in the gambia determined by restriction fragment profile analysis. | understanding genetic diversity of ehrlichia ruminantium in host and vector populations is an important prerequisite to controlling heartwater by vaccination in traditional livestock systems in sub-saharan africa. we carried out a study in two phases: (i) evaluating the usefulness of the pcr-rflp assay based on the map1 coding sequence of e. ruminantium as a discriminatory tool to characterise genetic diversity, (ii) applying the technique to field samples from amblyomma variegatum ticks and sma ... | 2008 | 17646061 |
| longitudinal monitoring of ehrlichia ruminantium infection in gambian lambs and kids by pcs20 pcr and map1-b elisa. | the epidemiology of e. ruminantium infection in extensively managed young animals is not adequately understood. thus in this study, we monitored the onset (age at first infection) and kinetics of e. ruminantium infection and antibody response in extensively managed newborn lambs and kids at three sites in the gambia. | 2007 | 17662144 |
| variegin, a novel fast and tight binding thrombin inhibitor from the tropical bont tick. | tick saliva contains potent antihemostatic molecules that help ticks obtain their enormous blood meal during prolonged feeding. we isolated thrombin inhibitors present in the salivary gland extract from partially fed female amblyomma variegatum, the tropical bont tick, and characterized the most potent, variegin, one of the smallest (32 residues) thrombin inhibitors found in nature. full-length variegin and two truncated variants were chemically synthesized. despite its small size and flexible s ... | 2007 | 17684009 |
| geographical distribution of ticks in turkey. | turkey's tick fauna is composed of about 32 species in two families and ten genera in mammals, reptiles, and birds. the ticks of veterinary significance in the family ixodidae comprise seven genera with 28 different species. ixodes spp. are mostly seen in northern turkey. it is likely that the high rainfall and the intensive forest in this area may contribute to this observation. to date, the following species have been found to be sporadically present: amblyomma variegatum in hatay province (bo ... | 2007 | 17823820 |
| global comparative analysis of ests from the southern cattle tick, rhipicephalus (boophilus) microplus. | the southern cattle tick, rhipicephalus (boophilus) microplus, is an economically important parasite of cattle and can transmit several pathogenic microorganisms to its cattle host during the feeding process. understanding the biology and genomics of r. microplus is critical to developing novel methods for controlling these ticks. | 2007 | 17935616 |
| cattle ticks of the genera rhipicephalus and amblyomma of economic importance in tanzania: distribution assessed with gis based on an extensive field survey. | in order to implement a robust integrated tick and tick-borne disease control programme in tanzania, based on ecological and epidemiological knowledge of ticks and their associated diseases, a national tick and sero-surveillance study was carried out in all 21 regions of the mainland, as well as on mafia island, between 1998 and 2001. the current distributions of rhipicephalus appendiculatus, r. pravus, amblyomma variegatum, a. gemma, and a. lepidum are illustrated and discussed. tick distributi ... | 2007 | 18044004 |
| identification and enzymatic activities of four protein disulfide isomerase (pdi) isoforms of leishmania amazonensis. | leishmania parasites primarily infect cells of macrophage lineage and can cause leishmaniasis in the skin, mucosal, and visceral organs, depending on both host- and parasite-derived factors. the protein disulfide isomerases (pdis) are thiol-disulfide oxidoreductases that catalyze the formation, reduction, and isomerization of disulfide bonds of proteins in cells. although four leishmania pdi genes are functionally inferred from homology in the genome sequences, only two of them have been express ... | 2008 | 18058133 |
| comparative sialomics between hard and soft ticks: implications for the evolution of blood-feeding behavior. | ticks evolved various mechanisms to modulate their host's hemostatic and immune defenses. differences in the anti-hemostatic repertoires suggest that hard and soft ticks evolved anti-hemostatic mechanisms independently, but raise questions on the conservation of salivary gland proteins in the ancestral tick lineage. to address this issue, the sialome (salivary gland secretory proteome) from the soft tick, argas monolakensis, was determined by proteomic analysis and cdna library construction of s ... | 2008 | 18070664 |
| climate changes and suitability for the ticks amblyomma hebraeum and amblyomma variegatum (ixodidae) in zimbabwe (1974-1999). | the spread of amblyomma hebraeum has been reported in zimbabwe. at the same time there was little or no spread in the distribution of amblyomma variegatum. this paper examines the climatic cycles and their trends in the period 1974-1999 with a view to explaining the abiotic causes of this spread, and of forecasting the likely tendency in climate suitability for both tick species. an annual data-set of rainfall and air temperature was used as a source for climate, together with a habitat-modeling ... | 2008 | 18083309 |
| variability and action mechanism of a family of anticomplement proteins in ixodes ricinus. | ticks are blood feeding arachnids that characteristically take a long blood meal. they must therefore counteract host defence mechanisms such as hemostasis, inflammation and the immune response. this is achieved by expressing batteries of salivary proteins coded by multigene families. | 2008 | 18167559 |
| an immunoglobulin binding protein (antigen 5) of the stable fly (diptera: muscidae) salivary gland stimulates bovine immune responses. | the stable fly, stomoxys calcitrans (l.) (diptera: muscidae), is an economically important pest of livestock. previous studies demonstrated lymphocyte suppression by crude salivary gland extract (sge) of the stable fly. a dominant 27-kda protein identified in the sge was reported to stimulate immunodominant antibody responses in exposed cattle. the purpose of this study was to determine whether this protein, now identified as ahomolog of insect proteins named antigen 5 (ag5), was responsible for ... | 2008 | 18283948 |
| a critical analysis of disease-associated dna polymorphisms in the genes of cattle, goat, sheep, and pig. | genetic variations through their effects on gene expression and protein function underlie disease susceptibility in farm animal species. the variations are in the form of single nucleotide polymorphisms, deletions/insertions of nucleotides or whole genes, gene or whole chromosomal rearrangements, gene duplications, and copy number polymorphisms or variants. they exert varying degrees of effects on gene action, such as substitution of an amino acid for another, shift in reading frame and prematur ... | 2008 | 18350334 |
| a novel sine family occurs frequently in both genomic dna and transcribed sequences in ixodid ticks of the arthropod sub-phylum chelicerata. | reassociation kinetics and flow cytometry data indicate that ixodid tick genomes are large, relative to most arthropods, containing>or=10(9) base pairs. the molecular basis for this is unknown. we have identified a novel small interspersed element with features of a trna-derived sine, designated ruka, in genomic sequences of rhipicephalus appendiculatus and boophilus (rhipicephalus) microplus ticks. the sine was also identified in expressed sequence tag (est) databases derived from several tissu ... | 2008 | 18394826 |
| amblyomma variegatum in cattle in marie galante, french antilles: prevalence, control measures, and infection by ehrlichia ruminantium. | we report marie galante as one of the caribbean islands most heavily infested by the tropical bont tick (tbt) amblyomma variegatum which is associated with two major diseases of ruminants: heartwater and dermatophilosis. in 2005, a survey was undertaken to assess the prevalence of tbt infestation in cattle, the prevalence of ehrlichia ruminantium infection in tbts, and the tick control measures implemented by livestock owners. a random sample of 195 cattle herds out of 1885 recorded on the islan ... | 2008 | 18406061 |
| insight into the sialome of the castor bean tick, ixodes ricinus. | in recent years, there have been several sialome projects revealing transcripts expressed in the salivary glands of ticks, which are important vectors of several human diseases. here, we focused on the sialome of the european vector of lyme disease, ixodes ricinus. | 2008 | 18489795 |
| immunomodulatory arsenal of nymphal ticks. | ticks have developed their own immunomodulatory mechanisms to inhibit the host inflammatory response. one of them involves the ability to subvert the cytokine network at the site of tick feeding by secreting cytokine binding molecules. most studies have focused on the immunomodulatory prowess of adult female ticks. here we describe anti-cytokine activity in salivary gland extracts (sges) prepared from 2-day-fed nymphs of dermacentor reticulatus fabricius, ixodes ricinus l., rhipicephalus appendi ... | 2008 | 18498617 |
| reliminary survey of ticks (acari: ixodidae) on cattle in central equatoria state, southern sudan. | in a preliminary survey conducted in 2005, the species composition and seasonality of ticks infesting cattle in central equatoria state, southern sudan was determined. three locations were selected (gumbo, khor rumla and nyaing) and surveyed every 3 months. two cattle herds in each of the three locations were visited four times during the study period. total body collections of ticks were made from each of five cattle (nilotic zebu breed) kept in six different herds. four tick genera and ten spe ... | 2008 | 18575063 |
| suppression of cell proliferation and cytokine expression by hl-p36, a tick salivary gland-derived protein of haemaphysalis longicornis. | previously, a putative immunosuppressant-coding gene was identified from a complementary dna library derived from the salivary glands of partially-fed haemaphysalis longicornis. using real-time polymerase chain reaction, the gene was shown to be predominantly expressed during blood feeding with the site of expression being mainly in the salivary glands; this was confirmed by western blotting analysis. to investigate the function of this novel protein, in this study, we examined the proliferative ... | 2009 | 18624730 |
| acute dermatitis caused by amblyomma variegatum larvae on chickens. | acute dermatitis caused by amblyomma variegatum larvae infestation was observed in adult local nigerian chickens. skin lesions containing numerous a. variegatum larvae were observed on gross examination. histopathology showed skin haemorrhages, larvae, necrosis and infiltration of eosinophils. it was suspected that the free range life of the birds could have predisposed them to the infestation. | 1990 | 18679988 |
| an insight into the salivary transcriptome and proteome of the soft tick and vector of epizootic bovine abortion, ornithodoros coriaceus. | the salivary glands of blood-sucking arthropods contain a redundant 'magic potion' that counteracts their vertebrate host's hemostasis, inflammation, and immunity. we here describe the salivary transcriptome and proteomics (sialome) of the soft tick ornithodoros coriaceus. the resulting analysis helps to consolidate the classification of common proteins found in both soft and hard ticks, such as the lipocalins, kunitz, cystatin, basic tail, hebraein, defensin, til domain, metalloprotease, 5'-nuc ... | 2008 | 18725333 |
| host surveys, ixodid tick biology and transmission scenarios as related to the tick-borne pathogen, ehrlichia canis. | the ehrlichioses have been subject to increasing interest from veterinary and public health perspectives, but experimental studies of these diseases and their etiologic agents can be challenging. ehrlichia canis, the primary etiologic agent of canine monocytic ehrlichiosis, is relatively well characterized and offers unique advantages and opportunities to study interactions between a monocytotropic pathogen and both its vertebrate and invertebrate hosts. historically, advances in tick-borne dise ... | 2008 | 18963493 |
| warmer weather linked to tick attack and emergence of severe rickettsioses. | the impact of climate on the vector behaviour of the worldwide dog tick rhipicephalus sanguineus is a cause of concern. this tick is a vector for life-threatening organisms including rickettsia rickettsii, the agent of rocky mountain spotted fever, r. conorii, the agent of mediterranean spotted fever, and the ubiquitous emerging pathogen r. massiliae. a focus of spotted fever was investigated in france in may 2007. blood and tissue samples from two patients were tested. an entomological survey w ... | 2008 | 19015724 |
| molecular detection of ehrlichia chaffeensis in amblyomma parvum ticks, argentina. | | 2008 | 19046533 |
| the use of a semiochemical bait to enhance exposure of amblyomma variegatum (acari: ixodidae) to metarhizium anisopliae (ascomycota: hypocreales). | experiments were conducted to explore the use of a semiochemical bait to enhance exposure of amblyomma variegatum fabricius (acari: ixodidae) to different formulations of the entomopathogenic fungus metarhizium anisopliae (metsch.) sorok. (ascomycota: hypocreales). initially, the relative efficacies of attraction-aggregation-attachment pheromone (aaap), made up of o-nitrophenol, methyl salicylate and nonanoic acid in the ratio 2:1:8, 1-octen-3-ol and butyric acid, were evaluated in an olfactomet ... | 2009 | 19091474 |
| ir-lbp, an ixodes ricinus tick salivary ltb4-binding lipocalin, interferes with host neutrophil function. | during their blood meal, ticks secrete a wide variety of proteins that can interfere with their host's defense mechanisms. among these proteins, lipocalins play a major role in the modulation of the inflammatory response. | 2008 | 19096526 |
| amblyomma variegatum ticks and heartwater on three caribbean islands. | amblyomma variegatum tick infestation, tick infection by ehrlichia ruminantium (er), and er genetic diversity were studied in the caribbean islands of guadeloupe, marie-galante, and antigua between 2003 and 2005. nested pcr for pcs20 was used to detect er, while er strains were characterized by sequencing or by restriction fragment length polymorphism (rflp) profiles of map-1 pcr products. in 2003 in guadeloupe, the prevalence of tick-infested herds was 35.6%. in marie-galante 79.1% of herds in ... | 2008 | 19120208 |
| bovine dermatophilosis, a re-emerging pandemic disease in zimbabwe. | to determine the current distribution of bovine dermatophilosis in zimbabwe, participatory rural appraisals were held at 36 locations in six districts. results showed that bovine dermatophilosis is no longer confined to hwange-lupane area, but is now endemic in gokwe, sanyati, kwekwe, and kadoma. virgin outbreaks of the disease were preceded by the appearance of amblyomma variegatum ticks within an area. spreading to new geographical areas (cited above) occurred during the liberation struggle (1 ... | 2009 | 19212820 |
| ixodid ticks infesting domestic goats in communal land areas of zimbabwe. | the purpose of this study was to determine the species spectrum of ticks infesting goats owned by resource-limited farmers in the state-owned communal land areas of zimbabwe. ticks were collected from goats at a single locality within each of 5 communal land areas, and a total of 14 ixodid tick species was recovered. the most numerous tick was rhipicephalus evertsi evertsi, which was present in all areas at each sampling, and a rhipicephalus sp. (near r. punctatus), which was most abundant on go ... | 2008 | 19244819 |
| the relationship between spotted fever group rickettsiae and ixodid ticks. | spotted fever group rickettsiae are predominantly transmitted by ticks. rickettsiae have developed many strategies to adapt to different environmental conditions, including those within their arthropod vectors and vertebrate hosts. the tick-rickettsiae relationship has been a point of interest for many researchers, with most studies concentrating on the role of ticks as vectors. unfortunately, less attention has been directed towards the relationship of rickettsiae with tick cells, tissues, and ... | 2009 | 19358804 |
| analysis of the rickettsia africae genome reveals that virulence acquisition in rickettsia species may be explained by genome reduction. | the rickettsia genus includes 25 validated species, 17 of which are proven human pathogens. among these, the pathogenicity varies greatly, from the highly virulent r. prowazekii, which causes epidemic typhus and kills its arthropod host, to the mild pathogen r. africae, the agent of african tick-bite fever, which does not affect the fitness of its tick vector. | 2009 | 19379498 |
| a resting box for outdoor sampling of adult anopheles arabiensis in rice irrigation schemes of lower moshi, northern tanzania. | malaria vector sampling is the best method for understanding the vector dynamics and infectivity; thus, disease transmission seasonality can be established. there is a need to protecting humans involved in the sampling of disease vectors during surveillance or in control programmes. in this study, human landing catch, two cow odour baited resting boxes and an unbaited resting box were evaluated as vector sampling tools in an area with a high proportion of anopheles arabiensis, as the major malar ... | 2009 | 19393098 |
| transovarial and trans-stadial transmission of rickettsiae africae in amblyomma variegatum ticks. | | 2009 | 19456811 |
| noncompetitive inhibitor of thrombin. | | 2009 | 19644995 |
| new approaches to detection and identification of rickettsia africae and ehrlichia ruminantium in amblyomma variegatum (acari: ixodidae) ticks from the caribbean. | imported from africa in the 1700s and despite frequent modern eradication efforts, amblyomma variegatum (f.) spread through the caribbean by cattle transport, small ruminants, and migrating birds. a. variegatum is a vector for rickettsia africae, the causative agent of african tick bite fever, and ehrlichia ruminantium, the causative agent of heartwater. we examined 95 a. variegatum and six rhipicephalus (boophilus) microplus (canestrini) collected from cattle at an abattoir in antigua. engorged ... | 2009 | 19645301 |
| detection of theileria parva antibodies in the african buffalo (syncerus caffer) in the livestock-wildlife interface areas of zambia. | a serolocigical survey was conducted for the detection of theileria parva antibodies in 176 african buffaloes (syncerus caffer) sampled between 1996 and 2005 in livestock-wildlife interface areas of zambia. rhipicephalus appendiculatus, rhipicephalus species, and amblyomma variegatum were the most abundant tick species identified on buffaloes. t. parva sero-positives were reported in buffaloes sampled from game management areas at mlanga and nanzhila bordering the kafue national parks and in the ... | 2009 | 19733007 |
| stone lakes virus (family togaviridae, genus alphavirus), a variant of fort morgan virus isolated from swallow bugs (hemiptera: cimicidae) west of the continental divide. | multiple isolates of an alphaviruses within the western equine encephalomyelitis-serocomplex that were related closely to ft. morgan and its variant buggy creek virus were made from swallow bugs, oeciacus vicarius horvath (hemiptera: cimicidae), collected from cliff swallow (petrochelidon pyrrhonota) nests at the stone lakes national wildlife refuge, sacramento county, ca, during the summers of 2005 and 2006. this virus (hereafter stone lakes virus, family togaviridae, genus alphavirus, stlv) wa ... | 2009 | 19769055 |
| analysis of amblyomma surveillance data in the caribbean: lessons for future control programmes. | amblyomma variegatum, the tropical bont tick (tbt), is the principal vector of heartwater and is associated with dermatophilosis, major causes of losses in animal production and mortality in caribbean livestock. from 1995 to 2007, the caribbean amblyomma programme (cap) supported treatment and surveillance activities in 11 islands of the eastern caribbean with an initial objective of eradicating tbt. in addition to control activities, surveillance data were collected between 1997 and 2006 in a u ... | 2010 | 19833441 |
| anti-chemokine activities of ixodid ticks depend on tick species, developmental stage, and duration of feeding. | ixodid ticks require comparatively large bloodmeals for their development and survival. blood-feeding elicits signaling events in the host leading to wound healing responses (hemostasis, inflammation, and tissue repair) and immunity. bioactive molecules present in tick saliva sabotage these host responses at several levels. one of them is neutralization of cellular communication by binding of specific saliva molecules to cytokines that have important roles in innate and adaptive immunity. chemok ... | 2010 | 19836889 |
| ectoparasites (sucking lice, fleas and ticks) of small mammals in southeastern kenya. | during 1998-2000, at least 14 species (n = 309) of small mammals were live-trapped and examined for ectoparasites in moist forests of the taita and shimba hills and drier savannah habitats of nguruman, southeastern kenya. ectoparasites were recorded from 11 species of mammals. five species of sucking lice [hoplopleura inexpectans johnson, h. intermedia kellogg & ferris, polyplax reclinata (nitzsch), p. waterstoni bedford and schizophthirus graphiuri ferris], six species of fleas (ctenophthalmus ... | 2009 | 19941604 |
| whartonacarus floridensis sp. nov. (acari: trombiculidae), with a taxonomic review and the first record of whartonacarus chiggers in the continental united states. | among several unusual species collected during surveillance of ectoparasites on wildlife hosts in the southeastern united states and caribbean region, the larvae of a new species of whartonacarus were encountered in 2003 on a cattle egret, bubulcus ibis (l.), in the florida keys. this is the first record for a member of whartonacarus in the continental united states. the mite is described and named as whartonacarus floridensis mertins, and the possible significance of this discovery with respect ... | 2009 | 19960669 |
| surveys for ectoparasites on wildlife associated with amblyomma variegatum (acari: ixodidae)-infested livestock in st. croix, u.s. virgin islands. | surveys in 2001, 2005, and 2006 attempted to determine the role of wildlife in maintenance and dissemination of the tropical bont tick, amblyomma variegatum (f.) (acari: ixodidae), in st. croix, u.s. virgin islands. small mammals; birds; white-tailed deer, odocoileus virginianus (zimmermann); and feral cattle, bos taurus l., were examined at nine premises, in mountainous rain forest, and in surrounding areas in western st. croix, an area including and central to all known bont tick-infested prem ... | 2009 | 19960701 |
| innovative approach for transcriptomic analysis of obligate intracellular pathogen: selective capture of transcribed sequences of ehrlichia ruminantium. | whole genome transcriptomic analysis is a powerful approach to elucidate the molecular mechanisms controlling the pathogenesis of obligate intracellular bacteria. however, the major hurdle resides in the low quantity of prokaryotic mrnas extracted from host cells. our model ehrlichia ruminantium (er), the causative agent of heartwater, is transmitted by tick amblyomma variegatum. this bacterium affects wild and domestic ruminants and is present in sub-saharan africa and the caribbean islands. be ... | 2009 | 20034374 |
| rhipicephalus (boophilus) microplus: clotting time in tick-infested skin varies according to local inflammation and gene expression patterns in tick salivary glands. | ticks deposit saliva at the site of their attachment to a host in order to inhibit haemostasis, inflammation and innate and adaptive immune responses. the anti-haemostatic properties of tick saliva have been described by many studies, but few show that tick infestations or its anti-haemostatic components exert systemic effects in vivo. in the present study, we extended these observations and show that, compared with normal skin, bovine hosts that are genetically susceptible to tick infestations ... | 2010 | 20045690 |
| performance of a metarhizium anisopliae-treated semiochemical-baited trap in reducing amblyomma variegatum populations in the field. | experiments were carried out to evaluate the efficacy of metarhizium anisopliae (metsch.) sorok. (ascomycota: hypocreales)-treated semiochemical-baited traps for control of amblyomma variegatum fabriscius (acari: ixodidae) under field conditions. unfed a. variegatum adults (118) were seeded in each 100-m plot and allowed to acclimatise for 3 days. on the fourth day (day 4), an emulsifiable formulation of m. anisopliae (consisting of 49.5% sterile distilled water, fungal conidia, 49.5% corn oil a ... | 2010 | 20153931 |
| biogeography of tick-borne bhanja virus (bunyaviridae) in europe. | bhanja virus (bhav) is pathogenic for young domestic ruminants and also for humans, causing fever and affections of the central nervous system. this generally neglected arbovirus of the family bunyaviridae is transmitted by metastriate ticks of the genera haemaphysalis, dermacentor, hyalomma, rhipicephalus, boophilus, and amblyomma. geographic distribution of bhav covers southern and central asia, africa, and southern (partially also central) europe. comparative biogeographic study of eight know ... | 2010 | 20182535 |
| ectoparasites are the major causes of various types of skin lesions in small ruminants in ethiopia. | ectoparasites are the major causes of skin lesions in animals. clinical, skin scraping examination, and histopathological studies were conducted to identify and characterize skin lesions in small ruminants caused by ectoparasites. mange mites, lice, sheep keds, and ticks were collected from the skin of affected animals for species identification. skin biopsies were collected from affected part of the skin and fixed in 10% neutral buffered formalin for histopathology. of 1,000 sheep and 600 goats ... | 2010 | 20195754 |
| rickettsia africae, western africa. | | 2010 | 20202453 |
| use of geographic information systems to identify areas at risk of introducing amblyomma variegatum and a. hebraeum to italy. | tick-borne diseases are one of the most important obstacles to the development of livestock breeding in africa. among these diseases, heartwater is of significant importance, second in rank to east coast fever. heartwater affects wild and domestic ruminants and is caused by a micro-organism belonging to the order rickettsiales, previously called cowdria ruminantium and recently renamed ehrlichia ruminantium. the disease is transmitted solely by ticks. although the aetiology and the clinical sign ... | 2007 | 20422545 |
| exploiting the heterogeneous drop-off rhythm of amblyomma variegatum nymphs to reduce pasture infestation by adult ticks. | tick distribution depends on the drop-off rhythm of the previous stage and on the suitability for tick survival of the environment where they are disseminated. studies were implemented in burkina faso to assess detachment pattern of engorged amblyomma variegatum nymphs. experiments were carried out with naturally infested cattle kept in a paddock or monitored when grazing community pasture. in the pasture, 80% of the nymphs detached between 14.00 h and 17.00 h while less than 25% did so in the p ... | 2010 | 20441678 |
| evasin-3-like anti-chemokine activity in salivary gland extracts of ixodid ticks during blood-feeding: a new target for tick control. | ticks exploit many evasion mechanisms to circumvent the immune control of their hosts including subversion of the communication language between cells of the immune system provided by chemokines and other cytokines. one subversive molecule secreted in the saliva of rhipicephalus sanguineus is evasin-3, a structurally unique 7 kda protein that selectively binds the neutrophil chemoattractants, cxcl8 and (with lower affinity) cxcl1. we compared anti-human cxcl8 and anti-mouse cxcl1/kc activities i ... | 2010 | 20500677 |
| toxicity of neem seed oil against the larvae of boophilus decoloratus, a one-host tick in cattle. | the in vitro toxicity of neem seed oil (azadirachta indica a. juss, family: meliaceae, dogon yaro in hausa language in nigeria) was tested against the larvae of a one-host tick, boophilus decoloratus (family: ixodidae or hard tick, commonly known as blue tick) parasitic mainly to cattle generally found in savannas of tropical equatorial africa. the 20, 40, 60, 80 and 100% concentrations of neem seed oil were found to kill all (100% mortality) the larvae after 27, 27, 27, 27 and 24 h respectively ... | 2009 | 20502579 |
| human ehrlichiosis and anaplasmosis. | human ehrlichiosis and anaplasmosis are acute febrile tick-borne diseases caused by various members of the genera ehrlichia and anaplasma (anaplasmataceae). human monocytotropic ehrlichiosis has become one of the most prevalent life-threatening tick-borne disease in the united states. ehrlichiosis and anaplasmosis are becoming more frequently diagnosed as the cause of human infections, as animal reservoirs and tick vectors have increased in number and humans have inhabited areas where reservoir ... | 2010 | 20513551 |
| survey of ixodid ticks in domestic ruminants in bedelle district, southwestern ethiopia. | a survey aimed at determining the status of ticks in cattle, sheep and goats in bedelle district (southwestern ethiopia) was carried out from november 2007 to april 2008. out of the total 330 animals examined, 314 (95.2%) were found to be infested (harbouring of at least a single tick). high rates of infestations were recorded across all three host species. factors like month of collection, age and sex of host species did not show significant association with infestation rates. a total of 5,507 ... | 2010 | 20563884 |
| moulting and survival of amblyomma variegatum (acari: ixodidae) nymphs in quasi-natural conditions in burkina faso; tick predators as an important limiting factor. | the survival rate of amblyomma variegatum engorged nymphs was studied in 9 cohorts released during the first part of the dry season (i.e. the nymph infestation period in the region) and placed on a natural savannah, either in plastic containers or in cages driven into the soil and open at the bottom. all nymphs put in the containers placed in the sun died rapidly, while a high moulting rate (94%) was observed in containers placed in the shade. this rate reached 63% for the ticks released in the ... | 2010 | 20593224 |
| comparative microarray analysis of rhipicephalus (boophilus) microplus expression profiles of larvae pre-attachment and feeding adult female stages on bos indicus and bos taurus cattle. | rhipicephalus (boophilus) microplus is an obligate blood feeder which is host specific to cattle. existing knowledge pertaining to the host or host breed effects on tick transcript expression profiles during the tick - host interaction is poor. | 2010 | 20637126 |
| an insight into the sialotranscriptome of the brown dog tick, rhipicephalus sanguineus. | rhipicephalus sanguineus, known as the brown dog tick, is a common ectoparasite of domestic dogs and can be found worldwide. r.sanguineus is recognized as the primary vector of the etiological agent of canine monocytic ehrlichiosis and canine babesiosis. here we present the first description of a r. sanguineus salivary gland transcriptome by the production and analysis of 2,034 expressed sequence tags (est) from two cdna libraries, one consctructed using mrna from dissected salivary glands from ... | 2010 | 20650005 |
| progress and obstacles in vaccine development for the ehrlichioses. | ehrlichia are tick-borne obligately intracellular bacteria that cause significant diseases in veterinary natural hosts, including livestock and companion animals, and are now considered important zoonotic pathogens in humans. vaccines are needed for these veterinary and zoonotic human pathogens, but many obstacles exist that have impeded their development. these obstacles include understanding genetic and antigenic variability, influence of the host on the pathogen phenotype and immunogenicity, ... | 2010 | 20822349 |
| tick-borne rickettsioses, neglected emerging diseases in rural senegal. | rickettsioses are one of the most important causes of systemic febrile illness among travelers from developed countries, but little is known about their incidence in indigenous populations, especially in west africa. | 2010 | 20856858 |
| identification of chelicerate neuropeptides using bioinformatics of publicly accessible expressed sequence tags. | while numerous investigations have focused on the identification of neuropeptides in arthropods, most have been conducted on members of the hexapoda or crustacea, and little is currently known about those in the chelicerata. here, publicly accessible expressed sequence tags (ests) were mined for putative chelicerate neuropeptide-encoding transcripts; the peptides encoded by the ests were deduced using on-line peptide prediction programs and homology to known isoforms. fifty-eight ests representi ... | 2010 | 20888826 |
| selection of reference genes for quantitative rt-pcr studies in rhipicephalus (boophilus) microplus and rhipicephalus appendiculatus ticks and determination of the expression profile of bm86. | for accurate and reliable gene expression analysis, normalization of gene expression data against reference genes is essential. in most studies on ticks where (semi-)quantitative rt-pcr is employed, normalization occurs with a single reference gene, usually beta-actin, without validation of its presumed expression stability. the first goal of this study was to evaluate the expression stability of commonly used reference genes in rhipicephalus appendiculatus and rhipicephalus (boophilus) microplu ... | 2009 | 20040102 |
| coxiella burnetii in humans and ticks in rural senegal. | q fever is a worldwide zoonotic disease caused by coxiella burnetii. epidemiologically, animals are considered reservoirs and humans incidental hosts. | 2010 | 20386603 |
| spread of parasites transported with their hosts: case study of two species of cattle tick. | like all parasites, ticks can be spread easily along with their hosts. ticks are obligate parasites of vertebrates, to which they attach themselves for varying periods of time, and are well-adapted to this mode of transport. once the transport stage is complete and they have detached at destination, they are also able to wait several months for the arrival of a new host on which they will continue their life cycle. this leads to the establishment of a secondary tick population. two tropical catt ... | 2010 | 20617654 |
| bm86 homologues and novel ataq proteins with multiple epidermal growth factor (egf)-like domains from hard and soft ticks. | tick control on livestock relies principally on the use of acaricides but the development of acaricide resistance and concerns for environmental pollution underscore the need for alternative control methods, for instance through the use of anti-tick vaccines. two commercial vaccines based on the recombinant bm86 protein from rhipicephalus (boophilus) microplus ticks were developed. partial protection of the bm86 vaccine against other rhipicephalus (boophilus) and hyalomma tick species suggests t ... | 2010 | 20647015 |
| efficacy of a doxycycline treatment regimen initiated during three different phases of experimental ehrlichiosis. | doxycycline is the treatment of choice for canine monocytic ehrlichiosis (cme), a well-characterized disease and valuable model for tick-borne zoonoses. conflicting reports of clearance of ehrlichia canis after treatment with doxycycline suggested that the disease phase during which treatment is initiated influences outcomes of these treatments. the purpose of this study was to evaluate the efficacy of a 28-day doxycycline regimen for clearance of experimental e. canis infections from dogs treat ... | 2010 | 20921310 |
| development of loop-mediated isothermal amplification (lamp) assays for rapid detection of ehrlichia ruminantium. | the rickettsial bacterium ehrlichia ruminantium is the causative agent of heartwater, a potential zoonotic disease of ruminants transmitted by ticks of the genus amblyomma. the disease is distributed in nearly all of sub-saharan africa and some islands of the caribbean, from where it threatens the american mainland. this report describes the development of two different loop-mediated isothermal amplification (lamp) assays for sensitive and specific detection of e. ruminantium. | 2010 | 21087521 |
| rickettsia africae in amblyomma variegatum and domestic ruminants on eight caribbean islands. | we used pcrs with omp a primers to determine if spotted fever group rickettsiae occurred in amblyomma variegatum from 6 caribbean islands. positive amplicons were obtained from ticks from the u.s. virgin islands (9/18; 50%), dominica (39/171; 30%), montserrat (2/5; 40%), nevis (17/34; 50%), st. kitts (46/227; 20%), and st. lucia (1/14; 7%). sequences for a convenience sample of reaction products obtained from a. variegatum on st. kitts (7), american virgin islands (4), montserrat (2), and st. lu ... | 2010 | 21158615 |
| rift valley fever virus(bunyaviridae: phlebovirus): an update on pathogenesis, molecular epidemiology, vectors, diagnostics and prevention. | rift valley fever(rvf) virus is an arbovirus in the bunyaviridae family that, from phylogenetic analysis, appears to have first emerged in the mid-19th century and was only identified at the beginning of the 1930's in the rift valley region of kenya. despite being an arbovirus with a relatively simple but temporally and geographically stable genome, this zoonotic virus has already demonstrated a real capacity for emerging in new territories, as exemplified by the outbreaks in egypt (1977), weste ... | 2010 | 21188836 |
| response of nkedi zebu and ankole cattle to tick infestation and natural tick-borne, helminth and trypanosome infections in uganda. | a cross-sectional study was conducted in soroti district of uganda to establish important traits of nkedi zebu and ankole cattle regarding their production performance responses to natural infections of trypanosomes, gastrointestinal nematodes, theileria parva, babesia bigemina, anaplasma marginale and tick infestations. over four visits between october 2006 to august 2007, tick counts were performed and blood, faecal samples and sera were collected from the nkedi zebu (295) and ankole (165) cat ... | 2011 | 21350849 |
| a further insight into the sialome of the tropical bont tick, amblyomma variegatum. | ticks--vectors of medical and veterinary importance--are themselves also significant pests. tick salivary proteins are the result of adaptation to blood feeding and contain inhibitors of blood clotting, platelet aggregation, and angiogenesis, as well as vasodilators and immunomodulators. a previous analysis of the sialotranscriptome (from the greek sialo, saliva) of amblyomma variegatum is revisited in light of recent advances in tick sialomes and provides a database to perform a proteomic study ... | 2011 | 21362191 |
| colonization of grande comore island by a lineage of rhipicephalus appendiculatus ticks. | union of the comoros suffered a severe east coast fever epidemic in 2004. rhipicephalus appendiculatus was probably involved in pathogen transmission as this competent tick species, although previously absent from comoros, was sampled on 4 animals on one geographical site during the epidemic. we carried out an entomological survey on all three islands of union of the comoros to establish cattle tick species distribution with a special emphasis on r. appendiculatus. we investigated r. appendicula ... | 2011 | 21414194 |
| risk factors for african tick-bite fever in rural central africa. | african tick-bite fever is an emerging infectious disease caused by the spotted fever group rickettsia, rickettsia africae, and is transmitted by ticks of the genus amblyomma. to determine the seroprevalence of exposure to r. africae and risk factors associated with infection, we conducted a cross-sectional study of persons in seven rural villages in distinct ecological habitats of cameroon. we examined 903 plasma samples by using an indirect immunofluorescence assay for antibodies to r. africae ... | 2011 | 21460018 |
| ehrlichia ruminantium in amblyomma variegatum and domestic ruminants in the caribbean. | the highly sensitive nested pcs20 polymerase chain reaction assay for ehrlichia ruminantium was negative on 506 amblyomma variegatum from caribbean islands where clinical heartwater has not been reported, mainly the united states virgin islands (18), dominica (170), montserrat (5), nevis (34), st. kitts (262), and st. lucia (17). positive results were obtained with positive controls (crystal springs strain) and a. variegatum from countries in africa where infections are endemic, mainly tanzania ... | 2011 | 21485394 |