evaluation of an enzyme-linked immunosorbent assay to detect specific antibodies in pigs infested with the tick ornithodoros erraticus (argasidae).ornithodoros erraticus is known to transmit the virus that causes the highly contagious disease, african swine fever, in spain. as part of the disease eradication campaign, an elisa test to detect specific antibodies against the tick was developed. the elisa, using salivary gland preparations as an antigen, showed high sensitivity and was able to detect as few as 10 adult ticks. the specific antibodies were detected in the sera 6 weeks after the primary infestation and strongly increased after t ...19902251748
distribution and biology of ornithodoros erraticus in parts of spain affected by african swine fever.ornithodoros erraticus was found in 30.7 per cent, 35.0 per cent and 71.0 per cent of the pig-pens sampled in the provinces of salamanca, badajoz and huelva in which african swine fever is a problem in the rearing of iberian pigs. between 38 and 65 per cent of the pig-pens in these areas are now abandoned and their populations of o erraticus are extinct or becoming so because they can no longer feed on pigs, which in spain are their main hosts. the abandonment of pig-pens has resulted in the eli ...19902301109
an argasid tick, ornithodoros erraticus (lucas) a natural vector of nuttalia meri gunders. preliminary communication. 19734778590
host immune response evasion strategies in ornithodoros erraticus and o. moubata and their relationship to the development of an antiargasid vaccine.we analysed in mice why the salivary gland extract (sge-2) from ornithodoros erraticus and o. moubata induce a protective response with freund's adjuvants (fas) in swine while the saliva, in natural conditions, does not. such protection has been ascribed to the fact that administration of sge-2 plus fas permits the recognition of certain salivary components that under natural conditions are not immunogenic. the present findings confirm this hypothesis since in mice, which are unable to recognize ...19979347516
antigens of interest for the diagnosis of parasitism in pigs by ornithodoros erraticus and ornithodoros moubata.we show by sodium dodecyl sulfate polyacrylamide gel electrophoresis and western blot that the composition of the soluble extracts of salivary glands (sge-2) of ornithodoros erraticus and ornithodoros moubata is similar to that of the saliva (pilocarpine-induced), and that the extracts are a valid source of antigens for the detection of anti-argasid antibodies. it is also shown that the sge-2s do not vary qualitatively with the developmental stage, physiological status, or sex of the ticks. the ...19979379286
babesiosis.babesiosis is an emerging, tick-transmitted, zoonotic disease caused by hematotropic parasites of the genus babesia. babesial parasites (and those of the closely related genus theileria) are some of the most ubiquitous and widespread blood parasites in the world, second only to the trypanosomes, and consequently have considerable worldwide economic, medical, and veterinary impact. the parasites are intraerythrocytic and are commonly called piroplasms due to the pear-shaped forms found within inf ...200010885987
first record of ornithodoros erraticus (lucas) from uganda, with some speculations on the origin of spirochaeta duttoni novy and knapp. 195213010161
[transmission of various relapsing fever causing spirochaetae by a sudanese strain of ornithodoros erraticus lucas (o.e. var. sonrai j. sautet, h. marneffe and m. witkowsky)]. 195513329731
identification of a new borrelia species among small mammals in areas of northern spain where lyme disease is endemic.the role of small mammals as reservoir hosts for borrelia burgdorferi was investigated in several areas where lyme disease is endemic in northern spain. a low rate of infestation by ixodes ricinus nymphs was found in the small mammal populations studied that correlated with the near-absence of b. burgdorferi sensu lato in 184 animals tested and with the lack of transmission of b. burgdorferi sensu lato to i. ricinus larvae that fed on them. in contrast, questing ticks collected at the same time ...200515746336
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 ...200818070664
function, mechanism and evolution of the moubatin-clade of soft tick lipocalins.the "moubatin-clade" of soft tick lipocalins, although monophyletic, shows clear signs of paralogy as indicated by the various functions associated with this protein family. this includes anti-platelet (moubatin), anti-complement (omci) and toxic (tsgp2) activities in the vertebrate host. in order to understand the evolution of function and how it relates to the various paralogs in this clade, we characterized a number of different proteins in regard to undefined function and mechanism. by utili ...200818694828
pathogenicity of endophytic entomopathogenic fungi to ornithodoros erraticus and ornithodoros moubata (acari: argasidae).the argasid ticks o. erraticus and o. moubata are of great medical and veterinary importance because they are vectors of the african swine fever virus and several species of human relapsing fever borreliae. biocontrol of these ticks using entomopathogenic fungi has not been previously reported. we examined the pathogenicity to different developmental stages of these two argasids of six strains of the fungal species beauveria bassiana (strains bb1764 and bb2157), lecanicillium lecanii (strains ll ...200818976863
a novel clade of cysteinyl leukotriene scavengers in soft ticks.inflammation is an important vertebrate defense mechanism against ecto-parasites for which ticks have evolved numerous mechanisms of modulation. am-33 and tsgp4, related lipocalins from the soft ticks argas monolakensis and ornithodoros savignyi bind cysteinyl leukotrienes with high affinity as measured by isothermal titration calorimetry. this was confirmed in a smooth muscle bioassay that measured contraction of guinea pig ileum induced by leukotriene c4 where both proteins inhibited contracti ...200818675910
purification and characterization of a 45-kda concealed antigen from the midgut membranes of ornithodoros erraticus that induces lethal anti-tick immune responses in pigs.ornithodoros erraticus is an argasid tick that can transmit severe diseases such as human relapsing fever and african swine fever. in the search for a vaccine against this parasite, a crude extract of tick midgut membranes (gme) was obtained that in pigs and mice induced a protective response able to kill up to 80% of the nymphs in the first 72 h post-feeding and to reduce the fecundity of females by more than 50%. to identify the protective antigens, the gme was subjected to successive biochemi ...200717337122
kinetics of african swine fever virus infection in ornithodoros erraticus ticks.the kinetics of african swine fever virus (asfv) infection in ornithodoros erraticus ticks were investigated in specimens collected in the field at different times following an outbreak of the disease in portugal in 1999 and in ticks infected experimentally with a virus isolated from a tick collected during this outbreak. in ticks collected from the field, initial screening for asfv was carried out by pcr, followed by attempts to isolate the virus in macrophage cultures. considering total number ...200616760388
borrelia hispanica relapsing fever, morocco.we found that 20.5% of patients with an unexplained fever in northwestern morocco had tick-borne relapsing fever. molecular detection specific for the 16s rrna gene identified borrelia hispanica. the noncoding intergenic spacer sequence domain showed high sensitivity and good resolution for this species.200919861058
glycerol-3-phosphate acquisition in spirochetes: distribution and biological activity of glycerophosphodiester phosphodiesterase (glpq) among borrelia species.relapsing-fever spirochetes achieve high cell densities (>10(8)/ml) in their host's blood, while lyme disease spirochetes do not (<10(5)/ml). this striking contrast in pathogenicity of these two groups of bacteria suggests a fundamental difference in their ability to either exploit or survive in blood. borrelia hermsii, a tick-borne relapsing-fever spirochete, contains orthologs to glpq and glpt, genes that encode glycerophosphodiester phosphodiesterase (glpq) and glycerol-3-phosphate transporte ...200312562805
purification, n-terminal sequencing and diagnostic value of the major antigens of ornithodoros erraticus and o. enhance the specificity and sensitivity of serological detection of swine exposed to ornithodoros erraticus or o. moubata, we purified the 158, 186, 215 and 260 kda antigens from the former species and the designated (owing to their mw and charge) 19c, 17a, 20a1 and 20a2 antigens of the latter by hplc and gel electroelution methods. all the o. erraticus antigens share epitopes and are difficult to purify individually by reverse phase and ion-exchange chromatography due to their molecular simi ...200010622611
a study of the vaccinal value of various extracts of concealed antigens and salivary gland extracts against ornithodoros erraticus and ornithodoros moubata.on pig farms, elimination of the argasid ticks acting as reservoirs and vectors for african swine fever greatly favours the eradication of this disease. the elimination of ornithodoros erraticus involves many problems, most of which could be easily solved by the development of an anti-o. erraticus vaccine. with a view to developing this vaccine, we have tested the protective value of the immune response induced in swine by seven 'concealed' antigens and one soluble salivary gland extract. the la ...19958644449
bloodmeal size and spirochete acquisition of ornithodoros hermsi (acari: argasidae) during feeding.ornithodoros hermsi wheeler (acari: argasidae) is the vector of borrelia hermsii, the primary cause of tick-borne relapsing fever in north america. this tick is one of the smallest ornithodoros species involved with the biological transmission of spirochetes; yet, the amount of blood ingested while feeding is unknown. therefore, we determined the amount of blood o. hermsi ingested during a bloodmeal to establish its potential for spirochete acquisition while feeding on an infected host. ticks at ...201021175068
detection of pig farms with ornithodoros erraticus by pig serology. elimination of non-specific reactions by carbohydrate epitopes of salivary antigens.ornithodoros erraticus is the european vector of african swine fever. it is therefore essential to know on which pig farms the tick is present in order to prevent contact with swine. currently, studies are being made to ascertain this through the detection of anti-o. erraticus antibodies in the sera of swine, using three extracts from the salivary glands of the parasite (sge): a complete extract (sge-1), a soluble antigens extract (sge-2), and a tissue antigens extract (sge-3). the results of th ...19948030193
clearance of african swine fever virus from infected tick (acari) colonies.three laboratory colonies of the argasid tick onithodoros moubata porcinus van der merwe were started from collections made in 1983 at three different sites in zimbabwe. all of the colonies contained ticks infected with african swine fever (asf) virus that was readily transmitted by bite to domestic pigs. although they were maintained on virus-free pig blood, asf virus infections persisted in the colonies for at least 1 yr. despite the fact that asf virus passes transstadially, sexually, and tra ...19892769711
relationships between the defensive systems of iberian-breed swine and the european vector of african swine fever, ornithodoros discover whether the immune system of iberian-breed pigs exerts any adverse action on ornithodoros erraticus, 3 pairs of pigs were subjected to a weekly infestation over 12 wk with 1,000 larvae, 500 nymphs-1, or 200 adults. each pair was bitten by only 1 developmental stage. batches of parasites identical to the foregoing ones were fed weekly on control swine. in none of the 10 parameters studied for each of the batches fed weekly was any significant difference found that could be attributed ...19902254823
analysis of the specificity of the salivary antigens of ornithodoros erraticus for the purpose of serological detection of swine farms harbouring the spain, considerable efforts are currently being devoted to the eradication of ornithodoros erraticus from the swine farms harbouring this parasite, the european vector of african swine fever (asf). however, to do so, a preliminary requirement is to determine on which farms it is present. of all possible methods for discovering this, the only one feasible for large scale application is the serological detection of swine bearing anti-o. erraticus antibodies. to apply serology it was necessary t ...19921373884
[deviation of the life cycle of dipetalonema viteae (filarioidea)].dipetalonema viteae is a filarial that can evoluate among hosts zoologically broadly apart (ixodides and argasides), but always gathered from meriones burrows. its evolution is, on the contrary, blocked among most of the other ticks, particularly among ornithodoros erraticus morphologically very similar to the normal vector. our work concerns the experimental deviation of the cycle of dipetalonema viteae, with its possible adaptability in the bosom of an intermediate of fowl tropism and a perman ...19761037623
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.200818167559
multiplex real-time pcr diagnostic of relapsing fevers in africa, relapsing fever borreliae are neglected arthropod-borne pathogens causing mild to deadly septicemia and miscarriage. the closely related borrelia crocidurae, borrelia duttonii, borrelia recurrentis and borrelia hispanica are rarely diagnosed at the species level, hampering refined epidemiological and clinical knowledge of the relapsing fevers. it would be hugely beneficial to have simultaneous detection and identification of borrelia to species level directly from clinical samples.201323390560
gene cloning, expression and immunogenicity of the protective antigen subolesin in dermacentor silvarum.subolesin (4d8), the ortholog of insect akirins, is a highly conserved protective antigen and thus has the potential for development of a broad-spectrum vaccine against ticks and mosquitoes. to date, no protective antigens have been characterized nor tested as candidate vaccines against dermacentor silvarum bites and transmission of associated pathogens. in this study, we cloned the open reading frame (orf) of d. silvarum 4d8 cdna (ds4d8), which consisted of 498 bp encoding 165 amino acid residu ...201424623890
a proteomic approach to the identification of salivary proteins from the argasid ticks ornithodoros moubata and ornithodoros erraticus.the saliva of ticks contains anti-haemostatic, anti-inflammatory and immunomodulatory molecules that allow these parasites to obtain a blood meal from the host and help tick-borne pathogens to infect the vertebrate host more efficiently. this makes the salivary molecules attractive targets to control ticks and tick-borne pathogens. although ornithodoros moubata and o. erraticus are important argasid ticks that transmit severe diseases, to date only a few of their salivary proteins have been iden ...200717916501
tick-borne infections in human and animal population worldwide.the abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors) presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous) developed during long co-evolving processes. ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. they are obligatory hematop ...201527047089
development of a nested pcr and its internal control for the detection of african swine fever virus (asfv) in ornithodoros erraticus.a nested pcr assay, with an internal control, was developed to detect african swine fever virus (asfv) dna in ornithodoros erraticus. the assay revealed a better analytical sensitivity than virus isolation and the oie pcr protocol. all ticks collected from the field, which were positive by virus isolation, were also positive by pcr. viral dna was detected in a further 19 out of 60 ticks from which no virus was isolated. our results show that this assay is reliable and can easily be used to scree ...200616328146
antigens from the midgut membranes of ornithodoros erraticus induce lethal anti-tick immune responses in pigs and mice.ornithodoros erraticus is an argasid tick that can transmit severe diseases such as human relapsing fever and african swine fever. in southern europe o. erraticus lives in close association with swine on free-range pig farms. application of acaricides for the eradication of o. erraticus from pig farms is inefficient. this is the reason why we tried to develop an anti-o. erraticus vaccine as alternative method of control. accordingly, we were prompted to investigate the protective possibilities o ...200616169153
relationship between the persistence of african swine fever and the distribution of ornithodoros erraticus in the province of salamanca, spain.for some time it has been known that the tick ornithodoros erraticus might be one of the causes of the persistence of african swine fever in the iberian peninsula since its introduction in 1960. in the province of salamanca serological methods have been used to study the relationship between the presence of the tick in different townships and the outbreaks of african swine fever in these townships between 1987 and 1992. the results showed that there was a statistically significant association be ...19947998382
the epidemiology and geographic distribution of relapsing fever borreliosis in west and north africa, with a review of the ornithodoros erraticus complex (acari: ixodida).relapsing fever is the most frequent bacterial disease in africa. four main vector / pathogen complexes are classically recognized, with the louse pediculus humanus acting as vector for b. recurrentis and the soft ticks ornithodoros sonrai, o. erraticus and o. moubata acting as vectors for borrelia crocidurae, b. hispanica and b. duttonii, respectively. our aim was to investigate the epidemiology of the disease in west, north and central africa.201324223812
highly sensitive pcr assay for routine diagnosis of african swine fever virus in clinical samples.this work provides a novel, highly sensitive, hot start pcr method for rapid and specific detection of african swine fever virus (asfv) that can be used as a routine diagnostic test for asfv in surveillance, control, and eradication programs. a confirmatory test of the specificity of this method based on restriction endonuclease analysis was also developed.200312958285
transmission routes of african swine fever virus to domestic pigs: current knowledge and future research directions.african swine fever (asf) is a major threat to the pig industry in europe. since 2007, asf outbreaks have been ongoing in the caucasus, eastern europe and the baltic countries, causing severe economic losses for many pig farmers and pork producers. in addition, the number of asf cases in wild boar populations has dramatically increased over the past few years. evidence supports direct contact with infectious domestic pigs and wild boars, and consumption of contaminated feed, as the main transmis ...026966305
serodiagnosis of louse-borne relapsing fever with glycerophosphodiester phosphodiesterase (glpq) from borrelia recurrentis.human louse-borne relapsing fever occurs in sporadic outbreaks in central and eastern africa that are characterized by significant morbidity and mortality. isolates of the causative agent, borrelia recurrentis, were obtained from the blood of four patients during a recent epidemic of the disease in southern sudan. the glpq gene, encoding glycerophosphodiester phosphodiesterase, from these isolates was sequenced and compared with the glpq sequences obtained from other relapsing-fever spirochetes. ...200011015364
hyperparasitism in ornithodoros erraticus.hyperparasitism is common in laboratory colonies of egyptian ornithodoros erraticus whether the ticks are on or off the rodent host. sex, recent engorgement, and size appear to be major factors in this feeding relationship. males, and nymphs that produced males (n-male), parasitized females and nymphs that produced females (n-female) more frequently than they parasitized males and n-male. females and n-female seldom parasitized females and n-female and did not parasitize males or n-male. engorgi ...19836827441
borrelia crocidurae localization and transmission in ornithodoros erraticus and o. savignyi.borrelia crocidurae infection rates in different organs of adult ornithodoros (pavlovskyella) erraticus and o. (ornithodoros) savignyi were studied at intervals during a 60-day period following an infective meal. the spirochaetes persisted in tick guts for 1 month, were first observed in other organs 1-7 days post-feeding, and persisted for 20-60 days in different organs. the ovaries, gene's organ, testes and male accessory glands of only o. erraticus were infected. the infection rates in adult ...19846739127
the epidemiology of tick-borne relapsing fever in iran during 1997-2006.tick-borne relapsing fever is an acute febrile and endemic disease in iran. for many reasons, the incidence of disease is on decrease, however tick-borne relapsing fever is still a health issue in the rural areas for travelers. this study was carried out during 1997-2006 to investigate the tick-borne relapsing fever in iran.200919411042
interactions between tick and transmitted pathogens evolved to minimise competition through nested and coherent networks.natural foci of ticks, pathogens, and vertebrate reservoirs display complex relationships that are key to the circulation of pathogens and infection dynamics through the landscape. however, knowledge of the interaction networks involved in transmission of tick-borne pathogens are limited because empirical studies are commonly incomplete or performed at small spatial scales. here, we applied the methodology of ecological networks to quantify >14,000 interactions among ticks, vertebrates, and path ...201525993662
the recent evolution of a maternally-inherited endosymbiont of ticks led to the emergence of the q fever pathogen, coxiella burnetii.q fever is a highly infectious disease with a worldwide distribution. its causative agent, the intracellular bacterium coxiella burnetii, infects a variety of vertebrate species, including humans. its evolutionary origin remains almost entirely unknown and uncertainty persists regarding the identity and lifestyle of its ancestors. a few tick species were recently found to harbor maternally-inherited coxiella-like organisms engaged in symbiotic interactions, but their relationships to the q fever ...201525978383
general review of tick species present in present, 24 species are known to occur in portugal: argas vespertilionis, ornithodoros maritimus and ornithodoros erraticus in argasidae; ixodes acuminatus, ixodes bivari, ixodes canisuga, ixodes frontalis, ixodes hexagonus, ixodes ricinus, ixodes simplex simplex, ixodes ventalloi, ixodes vespertilionis, dermacentor marginatus, dermacentor pictus', haemaphysalis hispanica, haemaphysalis inermis, haemaphysalis punctata, rhipicephalus bursa, rhipicephalus pusillus, rhipicephalus sanguineus, rhi ...199911071535
endemic foci of the tick-borne relapsing fever spirochete borrelia crocidurae in mali, west africa, and the potential for human infection.tick-borne relapsing fever spirochetes are maintained in endemic foci that involve a diversity of small mammals and argasid ticks in the genus ornithodoros. most epidemiological studies of tick-borne relapsing fever in west africa caused by borrelia crocidurae have been conducted in senegal. the risk for humans to acquire relapsing fever in mali is uncertain, as only a few human cases have been identified. given the high incidence of malaria in mali, and the potential to confuse the clinical dia ...201223209863
the cd2v protein enhances african swine fever virus replication in the tick vector, ornithodoros erraticus.the nh/p68 non-haemadsorbing (non-had) african swine fever virus (asfv) isolate contains frameshift mutations in the ep402r and adjacent ep153r genes. these encode, respectively, the protein (cd2v) that is required for the haemadsorption (had) of swine erythrocytes to asfv-infected cells and a c-type lectin protein. two recombinant had viruses were constructed in this parental strain. in one of these the intact ep153r gene sequence was restored. although restoration of the had phenotype did not ...200919729182
phylogenetic analysis of a virulent borrelia species isolated from patients with relapsing fever.multilocus sequence analysis (mlsa) was used to clarify the taxonomic status of a virulent borrelia organism previously isolated from patients with relapsing fever and from ticks in spain that is designated the spanish relapsing fever (srf) borrelia. this species has been used extensively in experimental infection models because of its continued virulence. seven genes were amplified to analyze the phylogenetic relationships among several spanish isolates of srf borrelia and other relapsing fever ...201020463158
the persistence of african swine fever virus in field-infected ornithodoros erraticus during the asf endemic period in portugal.african swine fever (asf) is an important disease of pigs and outbreaks of asf have occurred in europe on multiple occasions. to explore the period for which the european soft tick species ornithodoros erraticus (acari: argasidae) is able to act as a reservoir of african swine fever virus (asfv) after infected hosts are removed, we collected specimens from farms in the provinces of alentejo and algarve in portugal during the endemic period and tested them subsequently using cell culture and expe ...201121655242
Scabies mite peritrophins are potential targets of human host innate immunity.Pruritic scabies lesions caused by Sarcoptes scabiei burrowing in the stratum corneum of human skin facilitate opportunistic bacterial infections. Emerging resistance to current therapeutics emphasizes the need to identify novel targets for protective intervention. We have characterized several protein families located in the mite gut as crucial factors for host-parasite interactions. Among these multiple proteins inhibit human complement, presumably to avoid complement-mediated damage of gut ep ...201121980545
the medical and veterinary role of ornithodoros erraticus complex ticks (acari: ixodida) on the iberian peninsula.argasid ticks of the ornithodoros erraticus complex are associated with traditional pig-farming practices on the iberian peninsula and are also found elsewhere in north africa, west africa, and western asia. the ticks associated with pig farming on the iberian peninsula are the only biological vectors of african swine fever virus (asfv) known to occur in europe, and their ecology makes them an extremely effective reservoir of both asfv and the borrelia species which cause tick-borne relapsing fe ...201425424252
protection of european domestic pigs from virulent african isolates of african swine fever virus by experimental immunisation.african swine fever (asf) is an acute haemorrhagic disease of domestic pigs for which there is currently no vaccine. we showed that experimental immunisation of pigs with the non-virulent ourt88/3 genotype i isolate from portugal followed by the closely related virulent ourt88/1 genotype i isolate could confer protection against challenge with virulent isolates from africa including the genotype i benin 97/1 isolate and genotype x uganda 1965 isolate. this immunisation strategy protected most pi ...201121549789
borrelia crocidurae infection of ornithodoros erraticus (lucas, 1849) ticks in tunisia.tick-borne relapsing fever (tbrf) is caused by borrelia species transmitted to humans by infected ornithodoros sp. ticks. the disease has been rarely described in north africa, and in tunisia the local transmission of tbrf seems to have disappeared or is undiagnosed. a longitudinal study was conducted in 14 sites located in four different bioclimatic zones of tunisia to assess both the distribution of ornithodoros sp. and their infection rate with the relapsing fever borrelia sp. three polymeras ...201020420529
borrelia crocidurae: venereal transfer in egyptian ornithodoros erraticus ticks. 19826889976
tick-borne diseases in turkey: a review based on one health perspective.the importance of tick-borne diseases is increasing all over the world, including turkey. global warming, environmental and ecological changes and the existence of suitable habitats increase the impact of ticks and result in frequent emergence or re-emergence of tick-borne diseases (tbds) with zoonotic characteristics. in turkey, almost 19 tbds have been reported in animals and men, involving four protozoa (babesiosis, theileriosis, cytauxzoonosis, hepatozoonosis), one filarial nematode (acantho ...201627977689
relapsing fever borreliae in africa.the study of relapsing fever borreliae in africa has long suffered from the use of non-specific laboratory tools for the direct detection of these spirochetes in clinical and vector specimens. accordingly, borrelia hispanica, borrelia crocidurae, borrelia duttonii, and borrelia recurrentis have traditionally been distinguished on the basis of geography and vector and the unproven hypothesis that each species was exclusive to one vector. the recent sequencing of three relapsing fever borrelia gen ...201323926141
rickettsia felis, an emerging flea-borne rickettsiosis.rickettsia felis is an emerging insect-borne rickettsial pathogen and the causative agent of flea-borne spotted fever. first described as a human pathogen from the usa in 1991, r. felis is now identified throughout the world and considered a common cause of fever in africa. the cosmopolitan distribution of this pathogen is credited to the equally widespread occurrence of cat fleas (ctenocephalides felis), the primary vector and reservoir of r. felis. although r. felis is a relatively new member ...201627340613
typing african relapsing fever spirochetes.relapsing fever borrelia spp. challenge microbiologic typing because they possess segmented genomes that maintain essential genes on large linear plasmids. antigenic variation further complicates typing. intergenic spacer (igs, between 16s-23s genes) heterogeneity provides resolution among lyme disease-associated and some relapsing fever spirochetes. we used an igs fragment for typing east african relapsing fever borrelia spp. borrelia recurrentis and their louse vectors showed 2 sequence types, ...200516318724
processing and localization of the african swine fever virus cd2v transmembrane protein.the african swine fever virus (asfv)-encoded cd2v transmembrane protein is required for the hemadsorption of red blood cells around infected cells and is also required for the inhibition of bystander lymphocyte proliferation in response to mitogens. we studied the expression of cd2v by expressing the gene with a v5 tag downstream from the signal peptide near the n terminus and a hemagglutinin (ha) tag at the c terminus. in asfv-infected cells, a full-length glycosylated form of the cd2v protein, ...201121248037
borrelia hispanica in ornithodoros erraticus, portugal.clin microbiol infect abstract: tick-borne relapsing fever (tbrf) is a spirochetal infection caused by the genus borrelia. the disease is distributed in the old and new world with many different species reported. in europe, tbrf is caused by b. hispanica transmitted to man by ornithodoros erraticus, a soft tick usually found in old premises to shelter pig herds. in portugal, the first human case of tbrf was reported in 1942 but since the beginning of the 1960s, the disease has rarely been descri ...201121883668
genome sequence of the relapsing fever borreliosis species borrelia hispanica.borrelia hispanica is the etiological pathogen of tick-borne relapsing fever, transmitted to humans by infected ornithodoros erraticus ticks. here we present the 1,783,846-bp draft genome sequence, with an average g+c content of 28%. it has 2,140 open reading frames, 3 ribosomal rnas, and 32 transfer rnas.201424435869
epidemiology of tick-borne borreliosis in morocco.the presence in morocco of argasid ticks of the ornithodoros erraticus complex, the vector of tick-borne relapsing fever (tbrf) in north africa, has been known since 1919, but the disease is rarely diagnosed and few epidemiological data are available.201223029574
phylogenetic analysis of the spirochete borrelia microti, a potential agent of relapsing fever in iran.we report a role for borrelia microti as a cause of relapsing fever in iran supported by robust epidemiological evidence. the molecular identity of this spirochete and its relation with other relapsing fever borreliae have, until now, been poorly delineated. we analyzed an isolate of b. microti, obtained from ornithodoros erraticus ticks, by sequencing four loci (16s rrna, flab, glpq, intragenic spacer [igs]) and comparing these sequences with those of other relapsing fever borreliae. phylogenet ...201222718931
effect of o. porcinus tick salivary gland extract on the african swine fever virus infection in domestic pig.african swine fever is a haemorrhagic disease in pig production that can have disastrous financial consequences for farming. no vaccines are currently available and animal slaughtering or area zoning to restrict risk-related movements are the only effective measures to prevent the spread of the disease. ornithodoros soft ticks are known to transmit the african swine fever virus (asfv) to pigs in farms, following the natural epidemiologic cycle of the virus. tick saliva has been shown to modulate ...201626828597
multispacer sequence typing relapsing fever borreliae in africa, relapsing fevers are neglected arthropod-borne infections caused by closely related borrelia species. they cause mild to deadly undifferentiated fever particularly severe in pregnant women. lack of a tool to genotype these borrelia organisms limits knowledge regarding their reservoirs and their epidemiology.201222679518
african swine fever virus transmission cycles in central europe: evaluation of wild boar-soft tick contacts through detection of antibodies against ornithodoros erraticus saliva antigen.african swine fever (asf) is one of the most complex viral diseases affecting both domestic and wild pigs. it is caused by asf virus (asfv), the only dna virus which can be efficiently transmitted by an arthropod vector, soft ticks of the genus ornithodoros. these ticks can be part of asfv-transmission cycles, and in europe, o. erraticus was shown to be responsible for long-term maintenance of asfv in spain and portugal. in 2014, the disease has been reintroduced into the european union, affecti ...201626728767
midgut proteome of an argasid tick, ornithodoros erraticus: a comparison between unfed and engorged females.the argasid tick ornithodoros erraticus is the vector of african swine fever virus and of several borrelia species that cause human relapsing fever in the iberian peninsula. the tick midgut is part of the ectoparasite-host interface and expresses proteins that are vital for the survival of the tick. midgut proteins are therefore potential targets for drug and/or vaccine design aimed at the development of new strategies for tick control. thus, the aim of this work was the characterization of the ...201526459090
experimental infection of ornithodoros erraticus sensu stricto with two portuguese african swine fever virus strains. study of factors involved in the dynamics of infection in ticks.african swine fever (asf) is a frequently devastating hemorrhagic disease of domestic pigs and wild boar and ornithodoros erraticus sensu stricto argasid ticks are the only biological vectors of african swine fever virus (asfv) known to occur in europe. recently this disease emerged in eastern europe and russian federation, showing a huge potential for a rapid spread between countries. there is some risk of re-emergence of asf in the countries where these ticks exist, that can contribute for the ...201526366570
african swine fever virus strain georgia 2007/1 in ornithodoros erraticus ticks. 022607706
evaluation of bacillus thuringiensis pathogenicity for a strain of the tick, rhipicephalus microplus, resistant to chemical pesticides.the pathogenicity of four native strains of bacillus thuringiensis against rhipicephalus (boophilus) microplus (canestrine) (acari: ixodidae) was evaluated. a r. microplus strain that is resistant to organophosphates, pyrethroids, and amidines, was used in this study. adult r. microplus females were bioassayed using the immersion test of drummond against 60 b. thuringiensis strains. four strains, gp123, gp138, gp130, and gp140, were found to be toxic. for the immersion test, the total protein co ...201021062139
portuguese hosts for ornithodoros erraticus ticks.the hematophagous soft tick ornithodoros erraticus feeds nocturnally on multiple warm-blooded vertebrate hosts. this tick is often found living buried in the soil of traditional pigpens. o. erraticus is an important infectious disease vector both for humans and animals. in the iberian peninsula, this tick serves as the vector of human tick-borne relapsing fever caused by the spirochete borrelia hispanica. the natural ecosystems maintaining this spirochete are not well understood, with details of ...201323808979
subolesin/akirin orthologs from ornithodoros spp. soft ticks: cloning, rnai gene silencing and protective effect of the recombinant proteins.subolesin/akirin is a well characterized protective antigen highly conserved across vector species and thus potentially useful for the development of a broad-spectrum vaccine for the control of arthropod infestations including hard ticks, mosquitoes, sand flies and the poultry red mite dermanyssus gallinae. soft ticks could be also targeted by this vaccine if proved that the soft tick subolesin orthologs are conserved and induce protective immune responses too. however, to date no soft tick subo ...201122105082
characterization of pathogenic and non-pathogenic african swine fever virus isolates from ornithodoros erraticus inhabiting pig premises in portugal.ten african swine fever virus isolates from the soft tick ornithodoros erraticus collected on three farms in the province of alentejo in portugal were characterized by their ability to cause haemadsorption (had) of red blood cells to infected pig macrophages, using restriction enzyme site mapping of the virus genomes and by experimental infection of pigs. six virus isolates induced haemadsorption and four were non-haemadsorbing (non-had) in pig macrophage cell cultures. the restriction enzyme si ...200415269356
ornithodoros erraticus (lucas) in the jordan valley. 19715167440
cotransmission of divergent relapsing fever spirochetes by artificially infected ornithodoros hermsi.the soft tick ornithodoros hermsi, which ranges in specific arboreal zones of western north america, acts as a vector for the relapsing fever spirochete borrelia hermsii. two genomic groups (genomic group i [ggi] and ggii) of b. hermsii are differentiated by multilocus sequence typing yet are codistributed in much of the vector's range. to test whether the tick vector can be infected via immersion, noninfected, colony-derived o. hermsi larvae were exposed to reduced-humidity conditions before im ...201121965393
detection of a novel rickettsia from leptotrombidium scutellare mites (acari: trombiculidae) from shandong of china.leptotrombidium scutellare mites, the vector of orientia tsutsugamushi, have rarely been reported to associate with rickettsia species. three hundred nineteen chiggers were collected from the ears of 32 rodents captured in huangdao district of qingdao city, china, in october 2015. the chigger samples were tested for rickettsia, severe fever with thrombocytopenia syndrome virus, and hantavirus by pcr or rt-pcr amplification. all mites were classified morphologically and molecularly as l. scutella ...201728399204
ornithodoros erraticus (lucas) in antchat burrows. 195413183011
[the variety of toads which are hosts of ornithodoros erraticus and their role in the distribution of these arachnida and in their power of infection]. 195414369076
identification of protective linear b-cell epitopes on the subolesin/akirin orthologues of ornithodoros spp. soft ticks.subolesin/akirin is a protective antigen that is highly conserved across hematophagous vector species and is therefore potentially useful for the development of a universal vaccine for vector control, including soft ticks. recent results have shown that in ornithodoros erraticus and o. moubata soft ticks, rnai-mediated subolesin gene knockdown inhibits tick oviposition and fertility by more than 90%; however, vaccination with recombinant subolesins resulted in remarkably low protective efficacie ...201525597941
a description of ornithodoros erraticus (lucas) from kenya. 195214934032
use of a bayesian network model to identify factors associated with the presence of the tick ornithodoros erraticus on pig farms in southern portugal.the soft tick ornithodoros erraticus occurs on pig farms in southern portugal and spain and transmits several important pathogens of humans and livestock. its distribution is patchy and the determinants of its distribution are uncertain. here, we use a bayesian network model to explore possible associations between climate, farm management and the presence of o. erraticus. the resulting network confirms previous suggestions that the presence of o. erraticus is more likely in traditionally constr ...201323499360
[oviposition of the ornithodoros erraticus lucas 1849 under experimental conditions and several observations on its biology]. 201414857315
piroplasmal sporozoites in the argasid ornithodoros erraticus (lucas).the infective forms of nuttallia meri, a small-mammal piroplasm, first appear as spindle-shaped sporozoites in and around the salivary glands of ornithodoros erraticus (small race) 30 days after the ticks had fed on infected blood. o. erraticus is the only soft tick so far proved to transmit a piroplasm.1977891764
serological surveillance and direct field searching reaffirm the absence of ornithodoros erraticus ticks role in african swine fever cycle in sardinia.african swine fever (asf), one of the most important diseases of swine, has been endemic in the italian island of sardinia for more than 35 years. during these decades, several strategies and eradication efforts have been implemented in the island with limited success. strong climatic and ecological similarities exist between sardinia and one area of the iberian peninsula where ornithodoros erraticus ticks were involved in the persistence of asf from 1960 to 1995. this fact leads to the hypothes ...201726952266
[first report in italy of ornithodoros erraticus (lucas 1849)]. 200613419169
african swine fever: how can global spread be prevented?african swine fever (asf) is a devastating haemorrhagic fever of pigs with mortality rates approaching 100 per cent. it causes major economic losses, threatens food security and limits pig production in affected countries. asf is caused by a large dna virus, african swine fever virus (asfv). there is no vaccine against asfv and this limits the options for disease control. asf has been confined mainly to sub-saharan africa, where it is maintained in a sylvatic cycle and/or among domestic pigs. wi ...200919687038
detection of a novel rickettsia sp. in soft ticks (acari: argasidae) in algeria.argasid ticks are vectors of viral and bacterial agents that can infect humans and animals. in africa, relapsing fever borreliae are neglected arthropod-borne pathogens that cause mild to deadly septicemia and miscarriage. it would be incredibly beneficial to be able to simultaneous detect and identify other pathogens transmitted by argasid ticks. from 2012 to 2014, we conducted field surveys in 4 distinct areas of algeria. we investigated the occurrence of soft ticks in rodent burrows and yello ...201626408401
rickettsia lusitaniae sp. nov. isolated from the soft tick ornithodoros erraticus (acarina: argasidae).in this study a novel rickettsia from the spotted fever group, isolated from ornithodoros erraticus soft ticks collected from pigpens in the south of portugal, is described. after initial screening revealed rickettsia-positive ticks, isolation attempts were then performed. successful isolates were achieved by shell-vial technique using vero e6 cells at 28°c. molecular characterization of the isolate was performed based on analysis of five rickettsial genes glta, ompa, ompb, sca1 and htr with the ...201424513450
development of vaccines against ornithodoros soft ticks: an update.ticks are parasites of great medical and veterinary importance since they are vectors of numerous pathogens that affect humans, livestock and pets. among the argasids, several species of the genus ornithodoros transmit serious diseases such as tick-borne human relapsing fever (tbrf) and african swine fever (asf). in particular, ornithodoros erraticus is the main vector of these two diseases in the mediterranean while o. moubata is the main vector in africa. the presence of these ornithodoros tic ...201525802033
development of d. (a.) weissi, a macroscelid's filaria, in ornithodoros erraticus (author's transl).the microfilariae of d. (a.) weissi parasite of elephantulus rozeti in north africa evolved in ornithodoros erraticus (vellozo strain from casablanca) where they reach the infective stage. the filaria d. (a.) viteae, parasite of gerbillid rodents, is closely related to d. (a.) weissi but has some clear differential characters; on the contrary the infective stages seem to be undistinguishable.2011564155
acaricidal activity of fluralaner against ornithodoros moubata and ornithodoros erraticus argasid ticks evaluated through in vitro feeding.ornithodoros erraticus and ornithodoros moubata are argasid tick vectors that transmit severe diseases such as african swine fever and human relapsing fever. elimination of the synanthropic populations of these vectors would facilitate the control of these diseases. fluralaner is a novel isoxazoline that selectively blocks the gaba- and glutamate-gated channels, providing potent insecticidal and acaricidal activity. the aim of the current study was to provide quantitative data on the susceptibil ...201728807279
an overview on sardinia's soft ticks (ixodida: argasidae).knowledge about soft ticks (ixodida: argasidae) in sardinia is incomplete and distribution data need to be updated. this work studies soft ticks on the island focusing on two species, argas reflexus and ornithodoros maritimus, both recently recorded. a total number of 12 specimens of these species of interest were collected between 2004 and 2015. this study reports for the first time the presence of o. maritimus in a coastal area in italy, and more generally in a coastal area rather than small i ...201626940844
Displaying items 1 - 90 of 90