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isolation of tettnang virus from ticks, mosquitoes and small rodents.seven strains of tettnang virus were isolated in czechoslovakia: 3 from ixodes ricinus tick nymphs, males and females, one from dermacentor reticulatus tick females, one from aedes cantans mosquitoes and two strains from the brains of clethrionomys glareolus and apodemus flavicollis small rodents.197935963
electron microscopical studies on the development of babesia canis (sporozoa) in the salivary glands of the vector tick dermacentor reticulatus.the formation of sporozoites of babesia canis was studied by light- and electron microscopy in the salivary gland cells of adult female ticks from the 2nd day after attachment until 1 day after detachment. it was found that this process was initiated by the binary division of kinetes that had already entered or entered during the period examined. during division the kinetes (15 x 2.5 microns) lost their typical organelles, reduced their three-layered pellicle to a single membrane and became sphe ...197943086
three groups of babesia canis distinguished and a proposal for nomenclature.two stocks of large babesia from dogs originating in france, transmitted by dermacentor reticulatus, two from north africa, having rhipicephalus sanguineus as vector, and one from south africa, transmitted by haemaphysalis leachi, were compared in cross-immunity tests in dogs and in the indirect fluorescent antibody test (ifat). the french and north african stocks did not immunise against the south african one, while the north african stocks did not protect against a french one. the south africa ...19892655263
virus-like particles in dermacentor reticulatus ticks.virus-like particles were found in the brain and salivary glands of dermacentor reticulatus ticks double infected with coxiella burnetii and rickettsiella phytoseiuli. the particles were spherical (diameter of about 70 nm) and consisted of an electron-dense inner core and a dense external coat.19892576601
interaction between dermacentor reticulatus cells and coxiella burnetii in vivo.by electron microscopy the distribution of coxiella burnetii was followed in females of dermacentor reticulatus injected intracoelomally in a dose of about 10(3) eid50 per tick. the heaviest infestation with coxiellae was noticed in the cells of haemolymph, fat body, malpighian tubulus and tracheal complex. no rickettsiae were found in gene's organ. unexpected was the propagation of rickettsiae in muscle fibres. c. burnetii multiplied in all organs affected. heavy infection resulted at the marke ...19892576586
[the action of carbon dioxide gas in high concentrations on ixodid ticks].the ticks ixodes persulcatus, dermacentor reticulatus, d. marginatus were affected by 50, 70, 80 and 90% co2 at 18 to 26 degrees. the higher the gas concentration and the lower the temperature, the quicker and the deeper was anesthesia. additional tests have shown that response to co2 depends on the water balance level determining the position of atrial valves. the response of some individuals to co2 can change depending on the tick state during the experiment.19892501750
[ixodes ricinus, haemaphysalis concinna and dermacentor reticulatus (ixodida, ixodidae) in the east german district of leipzig].haemaphysalis concinna and dermacentor reticulatus mostly occur in narrow-limited humid biotopes of certain landscapes, whereas ixodes ricinus--as wellknown--occurs more or less occupying the whole territory in kind of a mosaic; in regard of epidemiological questions at least, such a distribution may be resumed for ixodes ricinus. haemaphysalis concinna nearly regularly may be found in certain biotopes. considering the possible role of haemaphysalis concinna and dermacentor reticulatus as vector ...19902389828
mixed infection of rickettsiella phytoseiuli and coxiella burnetii in dermacentor reticulatus female ticks: electron microscope study.mixed infection of rickettsiella phytoseiuli and coxiella burnetii was investigated in hemolymph and organs of experimentally infected females of dermacentor reticulatus ticks. following intracoelomic infection, both agents, with the exception of gene's organ, multiplied well in the cells of the tick host's organs. two out of six developmental stages of r. phytoseiuli, i.e., crystal-forming and small dark particles, in dual infection with c. burnetii revealed marked morphological alterations. c. ...19902351845
francisella tularensis from ixodid ticks in czechoslovakia.a total of 26,478 ixodid ticks (935 pools) were examined by intracerebral inoculation of suckling mice. six species of ticks were tested: ixodes ricinus (23,470 individuals), i. trianguliceps (12), haemaphysalis punctata (831), h. concinna (39), dermacentor reticulatus (69) and d. marginatus (2,057). the ticks were collected largely by flagging vegetation, a substantial minority (4%) from animals. three strains of francisella tularensis were isolated, one each from i. ricinus (males, district br ...19902227710
[babesiosis of dogs in germany: epidemiologic case analysis].between january 1987 and february 1990 babesia infections were detected in 320 dogs in germany by means of microscopical and/or serological methods. it was found, that 316 dogs were infected with babesia canis and 4 animals with babesia gibsoni. of the babesia-canis-positive dogs 184 were abroad up to 4 months before diagnosis, mainly in france, spain and italy, but also in hungary, greece, jugoslavia, portugal, morocco, togo, pakistan, sri lanka, malaysia, turkey, romania, austria and the nethe ...19912068714
longitudinal study of natural foci of central european encephalitis virus in west slovakia.a total of 2922 small terrestrial mammals of 12 species were collected in six localities of west slovakia between 1981 and 1986. when examined for the prevalence of neutralizing antibodies (na) to central european encephalitis (cee) virus we found that 14.6% had antibody. nearly all (97%) of the 426 animals with antibody were clethrionomys glareolus, the most abundant species (52.6% of mammals collected, 15.1% of those with antibody). apodemus flavicollis (22.5% of mammals collected, 18.1% of th ...19901983180
epidemiology of canine babesiosis in relation to the activity of dermacentor reticulatus in southern jura (france).dates of onset of canine babesiosis within a hyperendemic focus in france (rhone valley, south of jura and north of the alps) were compared to the seasonal population level of the adult stage of dermacentor reticulatus over a 12-month period (december 1982-november 1983). cases of babesiosis occurred in spring and fall when adult d. reticulatus were active. the fluctuations of the vector tick population and the onsets of canine babesiosis were also correlated with climatic changes: no tick activ ...19911893798
extensive examination of different tick species for infestation with coxiella burnetii in slovakia.between 1987-1989 almost 7000 adult ixodes ricinus, dermacentor reticulatus, dermacentor marginatus, haemaphysalis concinna, haemaphysalis punctata and haemaphysalis inermis ticks collected in all 38 districts of slovakia were screened for the presence of coxiella burnettii. the proportion of ticks containing c. burnetii as indicated by the haemocyte test was less than 3%. attempts to recover c. burnetii by inoculation of yolk sacs of embryonated hen eggs from pools of 1-6 specimens of haemocyte ...19911884784
[the ultrastructure of the interaction of rickettsia sibirica and r. slovaca with the cells of ixodid ticks].the ultrastructural aspects of the interaction of r. sibirica and r. slovaca with cells of mites of the species dermacentor reticulatus, d. marginatus and ixodes ricinus after their parenteral infection, as well as in the organs of d. marginatus infected naturally in the environment, have been studied. both rickettsial species have similar morphology in different organs of the vector. these rickettsiae not only multiply, their populations are also partly destroyed in phagolysosomes. the natural ...19911867038
endocytobionts in dermacentor reticulatus ticks (ixodidae): an electron microscope study.endocytobionts (ecbs) were detected in the ovaries of dermacentor reticulatus. their developmental cycle is directly related to the developmental stages of tick oocytes. two basic forms of ecbs occur in tick cells, i.e. dense forms, occurring singly or in aggregates situated free in the cytoplasm of host cells, and the light forms which are larger, pleomorphic and always situated inside vacuoles of host cells. the light forms occur together with dense forms in all oocytes. the dense forms occur ...19911860417
coxiella and rickettsiella: comparison of ultrastructure with special reference to their envelope.ultrastructure of rickettsiella phytoseiuli (r.p.) multiplying in female ticks dermacentor reticulatus was compared with that of coxiella burnetii (c.b.) in the same ticks and in mice. c.b. in ticks and mice were always represented by 2 main cell types: small dense round or rod-like cells (dc) and larger bacteria-like cells (bc). dc were surrounded with a characteristic five-layered 20 nm thick envelope. under the envelope dc had a stack of parallel intracytoplasmic membranes with a periodicity ...19911687641
mixed rickettsia-virus infection in dermacentor reticulatus imago.electron microscopic examination revealed replication and accumulation of rickettsia sibirica in the fat body of experimentally infected dermacentor reticulatus ticks. rickettsia are released from the fat body cells by budding being surrounded with cytoplasm and plasmalemma of the host cell. eukaryotic cell structures have been detected consisting of lamella layers whirled around the intact rickettsiae. in addition to rickettsia, microorganisms morphologically resembling francisella tularensis a ...19911681715
toxic effect of endocytobionts from dermacentor reticulatus ticks in three tick species after in vivo application.the endocytobionts from ovaries of partially engorged female dermacentor reticulatus ticks, inoculated introcoelomally into females of three tick species, d. reticulatus, ixodes ricinus and haemaphysalis inermis, caused considerable morphological alterations in the examined cells and tissues of the synganglion, fat body, tracheal complex and ovary of these recipients.19921638925
tick infection rates with borrelia: ixodes ricinus versus haemaphysalis concinna and dermacentor reticulatus in two locations in eastern germany.unfed nymphal ixodes ricinus, haemaphysalis concinna, and adult dermacentor reticulatus were collected in two locations of saxony in july and september 1991 by flagging. in july, the abundance of nymphal i. ricinus was about 2-3 times higher than that of nymphal h. concinna, a time of the year when nymphs of both species are reported to have a seasonal peak of activity. no d. reticulatus were flagged concurrently. in september, host-seeking activity of nymphal i. ricinus was again quite high as ...19921463902
[prevalence of the ticks dermacentor marginatus (sulzer, 1776) and dermacentor reticulatus (fabricius, 1794) and their importance as vectors of diseases in germany (author's transl)].from a systematical study of german ticks resulted the occurrence of two tick species of the genus dermacentor. d. marginatus is found to be widely spread in southern germany. adults of the tick feed mainly on sheep. d. reticulatus is first described from germany where the tick occurs endemic in a limited forest area on red deer. the two tick species are known from neighbouring countries of germany in transmitting virus, rickettsiae, bacteriae and protozoa but are not yet well studied in germany ...19761006797
[suburban biotopes of rhipicephalus turanicus (pomerancev, matikasvili, lototzki, 1940). (acarina, ixodoidea). preliminary study (author's transl)].investigations carried out on the waste grounds of a certain number of large mediterranean towns in provence and languedoc (france) show the prevalence of rhipicephalus turanicus in such an environment. the authors analyse the conditions favourable to the installation of the species, and make a comparison between the suburban biotopes with rhipicephalus turanicus and the homologous biotopes with dermacentor reticulatus.1977921194
[dermacentor reticulatus (fabr.) (ixodidae) in laboratory culture]. 1977899014
[survival time of dermacentor reticulatus (fabr.) (ixodidae) ticks infected per anum with tick-borne encephalitis virus (tbe)]. 1977899013
[new foci of dermacentor reticulatus (fabricius, 1794) in poland]. 1977899012
natural infection of the tick dermacentor reticulatus (fabr.) with the microsporidian nosema slovaca weiser et rehácek in slovakia.a total of 6,199 adult ticks (haemaphysalis intermis, dermacentor reticulatus, d. marginatus and ixodes ricinus) collected in three localities in slovakia were examined for microsporidian infection. the spores of nosema slovaca were found in six d. reticulatus (0.097%). the microsporidian experimentally inoculated into the hemocele of half-engorged females of d. reticulatus caused acute infection and death of the host. the infection can be transmitted also to other tick species from the same reg ...1978689565
experimental infection with rickettsiella phytoseiuli in adult female dermacentor reticulatus (ixodidae): an electron microscopy study.rickettsiella phytoseiuli naturally occurring in phytoseiulus persimilis mites was cultivated in adult female dermacentor reticulatus ticks. it demonstrates all six known developmental stages: dense, intermediate, bacterial, giant, crystal-forming and small dark particles. these stages of rickettsiae were found in salivary glands, malpighian tubules, synganglion, ovaries, tracheal complex, haemolymph, fat body and alimentary tract. rickettsiella phytoseiuli did not infect the gené's organ. it mu ...19892806015
[the meadow tick dermacentor reticulatus in natural foci of tick-borne encephalitis in udmurtia].in southern udmurtia, where occur both dermacentor reticulatus and ixodes persulcatus, in the years of high abundance of small mammals feeding periods of larvae and nymphs of these ticks coincide completely. the duration of simultaneous parasitism of preimago of the above ixodid species on animals is of epidemiological significance as far as within this period the infection of young stages of d. reticulatus with the virus of tick-borne encephalitis occurs. this is confirmed by the isolation of i ...19872963991
[ecology and pathogenic role of dermacentor reticulatus (fabricius, 1794) (ixodoidea) in the southeast of france]. 19744466309
the seasonal dynamics of the numbers of larvae in dermacentor reticulatus (fabricius, 1794) of the environs of czerwone bagno (red marsh). 19744454297
attempt to cultivate rickettsiella phytoseiuli in dermacentor reticulatus ticks: an electron microscopic study.rickettsiella phytoseiuli occurring in phytoseiulus persimilis mites was cultivated in dermacentor reticulatus ticks. rickettsiella multiplied similarly as in mites exerting all six developmental stages: dense, intermediate, bacterial, giant, crystal-forming and small dark particles.19882897779
[autochthonous babesiosis in dogs in the netherlands?].for the first time cases of babesiosis have been diagnosed in dogs that had not been abroad. three cases were seen in the province of gelderland (bennekom, elspeet), two in north-holland (koog aan de zaan). a female dermacentor reticulatus tick, the main vector of the disease in europe, was found on one of the dogs at koog; previously specimens of this tick species had only occasionally been seen on dogs returning from abroad. serological evidence was obtained that in at least four of the cases ...19853975891
a comparison of factors influencing the distribution of dermacentor reticulatus (ixodidae) in czechoslovakia and poland. 19863660811
[use of indirect immunofluorescence and polymerase chain reaction (pcr) for detection of borrelia burgdorferi in ticks].material samples from 40 ticks, including 30 ixodes ricinus and 10 dermacentor reticulatus ticks were tested for presence of borrelia burgdorferi infection with indirect immunofluorescence assay (if) and polymerase chain reaction (pcr). sensitivity of pcr in terms of minimum detectable number of in vitro cultivated spirochetes was a reproducible amplification when 50 spirochetes were added to the pcr mixture. the assay sensitivity was lower for b. burgdorferi in ticks and it was estimated on min ...19968927733
[ticks as a reservoir of borrelia burgdorferi and coxiella burnetii on polish terrain].the aim of performed studies was to recognize the distribution of coxiella burnetii and borrelia burgdorferi infected ticks in poland. the 1580 ticks infesting animals and humans were collected in different parts of the country. they belonged to ixodes ricinus, dermacentor reticulatus and argas reflexus species. presence of b burgdorferi and c. burnetii dna in ticks has been sought with polymerase chain reaction test (pcr). b. burgdorferi bacteria have been detected in 12 i. ricinus ticks (0.77% ...19968927734
[the discovery of dermacentor reticulatus (ixodida, ixodidae) in the east german districts of leipzig and halle].a report on findings of dermacentor reticulatus, a very rare tick species in the gdr, in 3 localities situated in the heath region of düben and dahlen (gdr districts of leipzig and halle). three adults of dermacentor reticulatus ticks were caught by brushing over the vegetation with a flag in one of 235 places in may and september 1987. on the other hand, a total of 2,877 ixodes ricinus ticks was found in all places. in the same year, from the same area, we also found 2 adults of dermacentor ret ...19883245638
[the tick fauna of eastern germany].the occurrence of several tick species in selected areas of eastern germany is described. from may 1987 till december 1989 8,472 ticks from 430 places were examined. ixodidae of the genus ixodes, dermacentor and haemaphysalis as well as argasidae of the genus argas were identified. the most common species was ixodes ricinus. furthermore, an endemic area of dermacentor reticulatus was detected in the düben-dahlen and annaburg health. two other species of ticks, which were found frequently and som ...19921416225
immunity of dogs against babesia canis, its vector tick dermacentor reticulatus, and ixodes ricinus in endemic area.previous epidemiological studies allowed us to accurately define endemic areas of canine babesiosis and tick distribution in southeastern france (martinod, 1983). using a micro-elisa test 100 dogs sera were tested with 3 antigens: babesia canis, dermacentor reticulatus and ixodes ricinus. antibodies against b. canis and its vector d. reticulatus were detected in an endemic area, sometimes with high levels (optical density 1.38 and 0.80 respectively). a correlation factor and regression lines wer ...19854009345
the replication and eclipse-phase of the tick-borne encephalitis virus in dermacentor reticulatus.particles of tick-borne encephalitis virus measuring 42-50 nm were found in in d. reticulatus nymphs after eclipse-phase lasting 10 days and were localized in epidermal and salivary gland cells.19846745800
experimental double infection with coxiella burnetii and tick-borne encephalitis virus in dermacentor reticulatus ticks.experimental parenteral inoculation of dermacentor reticulatus ticks with the rickettsia coxiella burnetii (c.b.) and tick-borne encephalitis (tbe) virus resulted in a generalized rickettsial and viral infection, irrespective of whether the agents were given simultaneously or by a 7 days interval apart. both agents multiplied intensively in ticks, c.b. being detectable predominantly in cytoplasmic vacuoles and tbe virus mostly in the endoplasmic reticulum.19872883860
preliminary studies on virus and spirochete accumulation in the cement plug of ixodid ticks.we provide evidence that tick-borne encephalitis virus and borrelia burgdorferi s.l. are accumulated in the cement plug in the host skin within the first few hours after tick attachment. extirpation of the tick without the cement plug, even very soon after the attachment, did not prevent the transmission by ixodes ricinus, ixodes persulcatus or dermacentor reticulatus to mice. this was within 1 hour in the case of the tbe virus and after 20-22 h of attachment, in the case of borrelia and i. pers ...19969004495
evidence for the reproductive isolation of dermacentor marginatus and dermacentor reticulatus (acari: ixodidae) ticks based on cross-breeding, morphology and molecular studies.the species status of dermacentor marginatus and dermacentor reticulatus was evaluated by scanning electron microscope (sem) examination of adult ticks, cross-breeding experiments and molecular biological analysis of eggs derived from transspecific pairings. the sem investigations including the morphometric quantification of phenotypic features resulted in an unequivocal differentiation of adult d. marginatus and d. reticulatus ticks. the cross-breeding experiments demonstrated that irrespective ...19979363622
salivary gland extracts of partially fed dermacentor reticulatus ticks decrease natural killer cell activity in vitro.the salivary glands and saliva of ticks (arachnida, acari, ixodida) play a vital role in blood feeding, including manipulation of the host's immune response to tick infestation. furthermore, a diverse number of tick-borne pathogens are transmitted to vertebrate hosts via tick saliva. a factor synthesized in the salivary glands of feeding ticks potentiates the transmission of certain tick-borne viruses. we show that salivary gland extracts (sge) derived from dermacentor reticulatus female ticks f ...19948045588
present state of research on ticks (ixodoidea) in the czech republic.tick research in the czech republic started developing rapidly after world war ii and was directed to the faunistics and taxonomy, biology, ecology and behaviour, physiology and genetics, disease transmission, host-parasite relationships and control. altogether 15 tick species were reported from the territory of the czech republic. most studies in biology, ecology and virus transmission were dedicated to ixodes ricinus, but biology and ecology of dermacentor reticulatus, i. laguri and i. hexagon ...19958553657
[suburban biotype of dermacentor reticulatus (fabricius, 1794) (ixodoidea). preliminary study]. 19734748108
[evolution of populations of ticks (ixodidae and argasidae) in relation to artificialization of the environment in the french alps. epidemiologic effects].the results presented in this study are based on observations made during some 10 years in the french alps and their surroundings. forest clusters, as they still cover comparatively large areas, are considered the most favorable foci for several ixodid species. recent studies, however, have shown that environment modified by man also harbours large populations of ticks. the spreading of certain species around and even into cities is actually taking place. the following categories of tick species ...19826131593
[borrelia burgdorferi infection of ticks in some regions of poland].ixodes ricinus and dermacentor reticulatus ticks were collected by flagging from the vegetation at five different locations in poland in may 1994. i. ricinus (n191) and d. reticulatus (n48), as well as 24 argas reflexus collected from katowice, kornie, szcyglice, urwitałt and zwierzyniec, were examined for the presence of borrelia spirochetes by the indirect immunofluorescent antibody test (ifa). borrelia were found in adult i. ricinus ticks at all 5 collection sites. nine out of 39 i. ricinus m ...19947597184
occurrence of borrelia spirochaetes in ticks (acari, ixodidae) collected in the forest areas in olsztyn province (north central poland).in 1993, 2178 out of 3816 ixodes ricinus and 45 out of 82 dermacentor reticulatus collected from vegetation at 35 sites and removed from hunter-killed deer in olsztyn province (n. c. poland) were examined individually for the presence of borrelia spirochaetes. detection of spirochaetes was carried out by the routine indirect immunofluorescence assay (ifa) using polyclonal antibody anti-b. burgdorferi, strain 1 b 29. borreliae, presumably b. burgdorferi, were evident in 192 (11.5%) i. ricinus (ny ...19937580351
enhancement of tick-borne encephalitis virus transmission by tick salivary gland extracts.to investigate the role of ticks in tbe virus transmission, salivary gland extract (sge) was derived from partially fed female ixodes ricinus, dermacentor reticulatus and rhipicephalus appendiculatus ticks. guinea-pigs were infested with uninfected r. appendiculatus nymphs and inoculated with a mixture of tbe virus and sge or with virus alone. the number of ticks which on average acquired virus from feeding on animals inoculated with tbe virus and sge from partially fed ticks was 4-fold greater ...19938481537
physiological age of ixodid ticks: aspects of its determination and application.this review analyzes 30 yr of data concerning physiological age of ixodid ticks. the level and state of nutritional reserves in unfed ticks has been proposed as an index of tick physiological age. the dynamics of the use of these substances reflect tick aging. thus, physiological age of ixodid ticks is determined by estimating the irreversible changes caused by natural vital activity in the body of unfed ticks, which inevitably raises the probability of tick death. the 4 age groups used in most ...19958551497
prevalence of ticks infected with francisella tularensis in natural foci of tularemia in western slovakia.the prevalence of ticks infected with f. tularensis was followed during a systematic surveillance in endemic area of tularemia in western slovakia over the years 1984-93. ticks were collected from vegetation in localities of podunajské biskupice, in the vicinity of the capital of slovakia, bratislava, near the river danube. in total 6033 ticks, mostly adults of dermacentor reticulatus and ixodes ricinus (4994 and 1004, respectively) and 35 nymphs of haemaphysalis concinna, were examined for the ...19958549717
[the ecology of hungry larvae of dermacentor reticulatus and their relation to food hosts under natural conditions].peculiarities of activation and regularities of spatial and temporary spread of hungry larvae of d. reticulatus from the progeny of one female were studied. activation of larvae occurs within 16 to 20 days. under natural conditions the activation of approximately 5 to 15% of potential number of individuals produced by a single clutch takes place. a larval aggregation occupies a territory of several square metres and survives about a month. larvae from two and more clutches feed simultaneously on ...19883226773
genetic evidence against a morphologically suggestive conspecificity of dermacentor reticulatus and d. marginatus (acari:ixodidae).international journal for parasitology 25: 1413-1419. dermacentor reticulatus and d. marginatus exhibit overlapping phenotypes. the possibility of conspecificity was investigated on the nucleotide level by comparing dna sequences of the second internal transcribed spacer (its 2) of the rdna gene. the inter-specific polymorphism was more than 20-times greater than the intra-specific polymorphism of 3 d. reticulatus strains of different geographic origins. furthermore, the degree of polymorphisms ...19958719952
bionomical and ecological characteristic of ticks (acari:ixodida) of significant medical importance on the territory of poland.among polish ticks species the most common in our country ixodes ricinus has the biggest medical importance. argasidae: argas reflexus, a. polonicus and ixodidae: ixodes trianguliceps, i. hexagonus and dermacentor reticulatus have significant medical meaning. argasidae are nests and burrows dwelling species having multi-host development cycle, they are mainly synanthropic and semisynanthropic, nocturnal active, with the peak seasonal activity in the middle of summer, dwelling semihumid or dry ha ...19968673794
distribution of borrelia burgdorferi s.l. spirochaete dna in british ticks (argasidae and ixodidae) since the 19th century, assessed by pcr.the distribution of borrelia burgdorferi sensu lato, the lyme borreliosis agent, was surveyed in british ticks in the collection of the natural history museum, london. alcohol-preserved specimens of eight species of ticks known to attack humans were studied: ixodes ricinus, i. hexagonus, i. uriae, i. trianguliceps, dermacentor reticulatus, haemaphysalis punctata, rhipicephalus sanguineus and argas vespertilionis. the sample comprised all life stages and originated from a wide range of host speci ...19989513944
frequent isolation of francisella tularensis from dermacentor reticulatus ticks in an enzootic focus of tularaemia.a total of 924 questing dermacentor reticulatus (fabricius), 504 ixodes ricinus (l.), sixty haemaphysalis concinna koch and 718 mosquitoes (aedes spp.) were examined in a floodplain forest ecosystem during the 1994-95 outbreak of tularaemia in south moravia, czech republic. francisella tularensis was not isolated from h.concinna ticks or aedes spp. mosquitoes, whereas twenty-one isolates were recovered from the other haematophagous arthropods. dermacentor reticulatus revealed a significantly hig ...19968887334
mosquitoes (diptera: culicidae), in contrast to ticks (acari: ixodidae), do not carry francisella tularensis in a natural focus of tularemia in the czech republic.in total, 9,167 mosquitoes (aedes spp.) and 1,987 ixodid ticks--1,423 dermacentor reticulatus (f.), 504 ixodes ricinus (l.), and 60 haemaphysalis concinna koch--were examined in an active enzootic focus (floodplain forest-meadow ecosystem) of tularemia in south moravia. czech republic. although no f. tularensis was detected in mosquitoes or h. concinna, 30 isolates were recovered from d. reticulatus (infection rate, 2.1%) and 1 isolate from i. ricinus (infection rate, 0.2%). ixodid ticks, especi ...19979439120
a comparison of developmental dynamics of dermacentor reticulatus (fabr.) of different geographic origins and their affection by different microclimate.developmental dynamics of d. reticulatus ticks of different geographic origins (ne poland and sw slovakia) were investigated and compared. a long-term field experiment was conducted in south moravia in the zone of thermophilic oak forest. ticks were studied in two different biotopes: in an open grassy area and in deciduous forest. differences between the tick populations collected in poland and slovakia were observed in the duration of developmental cycle and in the outcome of metamorphosis, dep ...19807364348
light and electron microscopic study on developmental stages of babesia canis within the gut of the tick dermacentor reticulatus.the initial developmental stages of babesia canis within the gut of the vector tick, dermacentor reticulatus, were studied by means of light and electron microscopy. large quantities of varying "spiky-rayed" stages and few ovoid stages without any protrusions were observed after lysis of the engorged canine erythrocytes. the transformation of spherical erythrocytic stages into "spiky-rayed" forms was initiated inside the intact erythrocytes. the significance of all developmental stages in a hypo ...19807391862
[the subspecies specificity of babesia canis].the large babesia species of dogs, babesia canis, is transmitted by different ticks. dermacentor reticulatus, rhipicephalus sanguineus and haemaphysalis leachi are the known main vectors. four b. canis isolates of different geographic origin were investigated for their transmission specificity and pathogenicity in infection trials. r. sanguineus ticks exclusively transmitted the babesia isolate from egypt. d. reticulatus was the vector for isolates from hungary and france. transmission of an sou ...19968765536
imidocarb: a chemoprophylactic experiment with babesia canis.eight dogs, given imidocarb dipropionate subcutaneously at a dose of 6 mg/kg, were challenged with a sporozoite stabilate of a french strain of babesia canis, prepared from infected dermacentor reticulatus ticks, 2, 3, 4 or 5 weeks after treatment. three control dogs were similarly infected but not preventively treated. one of the controls and one of the dogs treated 5 weeks prior to challenge died of babesiosis. prepatent and incubation periods were similar in treated and control dogs, and all ...19817268745
effect of temperature and humidity on longevity of unfed adults and on oviposition of engorged females of dermacentor reticulatus (ixodidae).the effect of ambient temperature and relative humidity on longevity of unfed adult ticks and on oviposition of engorged female ticks of dermacentor reticulatus was examined. the 50% mortality time of unfed adult ticks, incubated at 5 degrees c, 10 degrees c, 20 degrees c and 27 degrees c and humidities of 15%, 50% and 100%, increased irrespective of their sex with rising relative humidity and decreasing temperature. it was longest at 5 degrees c and 100% r.h. being 617.8 days and shortest at 27 ...19958541893
detection and typing of borrelia burgdorferi sensu lato in ixodes ricinus ticks attached to human skin by pcr.live ixodes ricinus ticks attached to humans residing in germany were examined for borreliae by dark-field microscopy and pcr. borrelia species were identified by 16s rrna sequence analysis, which showed the presence of several species, some not yet defined, and a high prevalence of multiply infected ticks.19989774593
feeding of dermacentor reticulatus (fabr.) females depending on their age, origins and biotope of survival.in dermacentor reticulatus (fabr., 1794) females originating from slovakia and poland the duration of feeding on host and its successful outcome depending on the age, origins of ticks and biotope of their survival was studied. in specimens older than a half year no influence of these factors on the duration of feeding was demonstrated. with increasing age the ability of full engorgement did no diminish. the data obtained indicate the possibility that a higher percentage of females of equal age e ...19807450613
[dermacentor ticks in france and germany. molecular biological differences in species, ecology and epidemiological implications].dermacentor reticulatus and d. marginatus, two ixodid tick species occurring in france and germany, exhibit morphologically overlapping phenotypes. the results of sequence analyses of the hypervariable rdna gene region its 2 do not support conspecifidity. as in france, d. reticulatus has to be characterized as an epidemiologically effective vector of babesia canis in germany as well, with the endemic area being located at kehl/offenburg/lahr/emmendingen/freiburg in breisgau. ecological investiga ...19968767177
[imported arthropod-borne parasites and parasitic arthropods in dogs. species spectrum and epidemiologic analysis of the cases diagnosed in 1995/96].between january 1995 and december 1996 nonendemic or only regionally occurring arthropodborne parasites including ehrlichiae and parasitic arthropods in germany were detected in 484 dogs, whereby at least 15 species were involved. listed in decreasing order, leishmania infections occurred most frequently, followed by infections/infestations with babesia canis, ehrlichia canis, rhipicephalus sanguineus, dirofilaria immitis and dermacentor reticulatus. the other species, namely babesia gibsoni, tr ...19989531673
incidence from coincidence: patterns of tick infestations on rodents facilitate transmission of tick-borne encephalitis virus.tick-borne encephalitis (tbe) virus has a highly focal distribution through eurasia. endemic cycles appear to depend on the transmission of non-systemic infections between ticks co-feeding on the same rodent hosts. the particular features of seasonal dynamics and infestation patterns of larval and nymphal ixodes ricinus, but not dermacentor reticulatus, from 4 regions within tbe foci in slovakia, are such as to promote tbe virus transmission. the distributions of larvae and nymphs on their princ ...199910028532
[a focus of dermacentor reticulatus kept by red and fallow deer in animal husbandry (kosewo, poland)].focus of dermacentor reticulatus has been found on the area of fenced cervides farm. very frequent occurrence of d. reticulatus on plants of red and fallow deer pens indicates that these animals in farm conditions are good hosts of adult forms of this tick. on pens of red deer the number of ticks caught on plants was considerable greater than on pens of fallow deer. however, proportion of males in spring and autumn populations of ticks caught on fallow deer pens was considerable greater than on ...19979424941
investigation of haematophagous arthropods for borreliae--summarized data, 1988-1996.blood-sucking arthropods, collected in south moravia, czech republic, were examined by darkfield microscopy for borreliae from 1988 to 1996. among host-seeking ixodid ticks (8481 ixodes ricinus (l.), 372 dermacentor reticulatus (fabr.), 167 haemaphysalis concinna koch), borreliae were only observed in adult (23.2%), nymphal (17.2%) and larval (6.3%) i. ricinus. the prevalence of borreliae in i. ricinus did not vary considerably among habitats except for lower values in agroecosystems, xerothermi ...19989516997
investigation of anaplasma phagocytophila infections in ixodes ricinus and dermacentor reticulatus ticks in austria. 200312860606
[parasitic arthropods of bison bonasus from the białowieza primeval forest].during the period 1991-1993, 61 bisons from the białowieza primaeval forest were examined. 8 species of ectoparasites were noted: bovicola sedecimdecembrii, lipoptena cervi, dermacentor reticulatus, ixodes ricinus, ixodes persulcatus, chorioptes bovis, psoroptes ovis, demodex bisonianus. the most frequent incidence noted was d. bisonianus, prevalence 52%, followed b. sedecimdecembrii--28%, i. ricinus--12% and l. cervi 8%.19968967085
importance of surveillance of tularemia natural foci in the known endemic area of central europe, 1991-1997.marked activation of natural foci of tularemia in the known endemic area of central europe, comprising the borderland of slovakia, austria and the czech republic, led to an epidemic outbreak in western slovakia and an increase in the number of human tularemia cases in the adjoining regions of northeastern austria and southern moravia from 1995 to 1997. the aim of this paper was to present the results of a longitudinal study on the prevalence of infection with francisella tularensis in small mamm ...200111467089
use of partially engorged female ticks as laboratory animals in microbiological research.partially engorged female ticks were used as laboratory animals in microbiological research. the ticks, which were inoculated intracoelomally, became a convenient substrate for the detection of viruses, rickettsiae and protozoal parasites. this research concerned the isolation of newly recovered micro-organisms, the study of development, structure and distribution of microbial agents in ticks, and the study of their interaction with other pathogens or symbionts during mixed infection in a tick b ...19948025326
comparison of the protein profiles of salivary gland extracts derived from three species of unfed and partially fed ixodid ticks analysed by sds-page.salivary gland extracts (sge) from unfed and 5 days fed adult female ixodes ricinus (linnaeus, 1758); haemaphysalis inermis (birula, 1895) and dermacentor reticulatus (fabricius, 1794) ticks were prepared. the protein content after feeding increased by 10.6, 8.7 and 6.8 times, respectively. extracts were equilibrated to the same protein content and submitted to sds-polyacrylamide gel electrophoresis followed by computer analysis of the scanned gels. relative differences in protein profiles of ex ...200010833019
prevalence of francisella tularensis in dermacentor reticulatus ticks collected in adjacent areas of the czech and austrian republics.a total of 1098 host-seeking adult dermacentor reticulatus ticks were examined in an active enzootic focus (floodplain meadow and forest ecosystem) of tularemia along the lower reaches of the thaya (dyje) river in south moravia (czech republic) and adjacent austria during the spring of 1996. twenty-five isolates of francisella tularensis were recovered (i.e., the overall minimum infection rate was 2.3%). the prevalence rate varied between 0.6% and 3.5% among four localities examined (two in mora ...19979457420
effect of temperature and humidity on egg hatch, moulting and longevity of larvae and nymphs of dermacentor reticulatus (ixodidae).larvae of dermacentor reticulatus hatched at a temperature range of 20-34 degrees c, but a high egg hatch success of > 90% was only achieved at 20 degrees c and 27 degrees c and 100% r.h. the developmental capability of the eggs at low or freezing temperatures persisted up to 3 weeks at -10 degrees c and up to 8 weeks at 5 degrees c. the 50% mortality period of unfed larvae and nymphs increased with rising humidity and was longest at 5 degrees c and 100% r.h., amounting to 83.5 days for larvae a ...19957780450
francisella tularensis in dermacentor reticulatus ticks from the czech republic and austria.host-seeking adult dermacentor reticulatus ticks were examined for the prevalence of francisella tularensis in an active natural focus of tularemia along the lower reaches of the dyje (thaya) river in south moravia (czech republic) and adjacent lower austria, in four localities of the flood plain forest-meadow ecosystem during the spring of 1996. the ticks were pooled (10 male or female ticks per group) and inoculated subcutaneously in 4-week-old spf mice. dead mice were sectioned, the spleens w ...199810048175
tick salivary gland extract inhibits killing of borrelia afzelii spirochetes by mouse macrophages.salivary gland extract (sge) from ixodes ricinus ticks inhibited the killing of borrelia afzelii spirochetes by murine macrophages. sge also reduced the production of two major defense molecules of phagocytes, superoxide and nitric oxide. it is likely that the suppression of macrophage microbicidal mechanisms contributes to the inhibitory effect of tick saliva on the killing of b. afzelii spirochetes, thus facilitating the transmission of this important pathogen.200111119556
internal and external mycoflora of the american dog tick, dermacentor variabilis (acari: ixodidae), and its ecological implications.scopulariopsis brevicaulis, the anamorph of microascus brevicaulis (microascaceae, ascomycota), has been identified in the body contents of the tick dermacentor variabilis. after topical application of the fungal inoculum, tick mortality was marked. this is the first account describing the internal mycoflora of d. variabilis with a novel technique used to recover potential biological control agents.200312902299
modus operandi of oviposition in dermacentor reticulatus (acari: ixodidae).the process of oviposition in d. reticulatus was observed and found to be a sequence of exactly coordinated, interlocking events independent of the phase of oviposition. the average period of oviposition in the investigated ticks was 31.6 days at 20 degrees c and 95% relative humidity. the number of eggs deposited on each day increased until reaching a maximum on the fifth day of oviposition and then decreased continuously. as a result, most of the eggs were deposited during the initial phase of ...200010823358
anti-interleukin-8 activity of tick salivary gland extracts.interleukin-8 (il-8) is one of many mammalian chemokines (chemotactic cytokines) that direct mammalian inflammatory and immune cells to sites of injury and infection. chemokines are produced locally and act on leucocytes through selective receptors. the principal role of il-8 is to control the movement and activity of neutrophils. to date, several tick species have been shown to modulate the production or activity of certain cytokines but none of these are chemokines. using an il-8 specific elis ...200111589777
[the activity of dermacentor reticulatus fabr. (ixodidae) ticks in nature].the experimental population-based ecological parameters most closely associated with the age of ticks, including activity, were assessed in the d. reticulatus imago (moscow province). the activity rise of ticks in autumn is twice as low as that in spring, with their inactivity in summer. there are some seasonal variations in the ratio of males to females. evidence has been first provided for the maximum duration (more than 2.5 years, about 1%) of active life till the third spring when the colour ...199810050544
inhibition of the antiviral action of interferon by tick salivary gland extract.the saliva of haematophagous arthropods (e.g. mosquitoes, sandflies and ticks) contains potent immunomodulatory activities that counter their hosts' haemostatic, inflammatory and immune responses to facilitate blood-feeding. such effects are exploited by arthropod-transmitted pathogens to promote their transmission. we investigated the ability of tick saliva to enhance arthropod-borne virus (arbovirus) transmission by determining its effect on the antiviral action of murine interferon (ifn alpha ...200010760186
[endemic risk of babesia canis by dermacentor reticulatus in germany. an epidemiologic study].during the period of january 1995 to january 1997, babesia canis infections were diagnosed in 127 dogs, 65 of them had stayed in foreign countries where dermacentor reticulatus is endemic, namely france, austria and hungary, or in the area offenburg/kehl/freiburg i. breisgau (germany). two dogs being positive for babesia never had left germany before and had not been in the region offenburg/kehl/freiburg i. breisgau. concurrent tick infestations were reported for all of the 67 dogs. for 10 dogs ...19979459834
morphology and structural organization of gené's organ in dermacentor reticulatus (acari: ixodidae).scanning and transmission electron microscopical investigations revealed that genés organ in unfed and ovipositing females of dermacentor reticulatus is formed as a double-sac-structure consisting of an outer epithelial and an inner cuticular sac. in ovipositing ticks the latter emerges through the camerostomal aperture to the exterior. genés organ in unfed ticks consists of a corpus, two posterior horns and a pair of undeveloped glands at each side, which differentiate in ovipositing ticks to c ...200111603740
babesia dna detection in canine blood and dermacentor reticulatus ticks in southwestern siberia, russia.babesia infection was studied in 21 blood samples of dogs with symptoms of babesiosis and among 72 dermacentor reticulatus and 70 ixodes persulcatus ticks from southwestern siberia, russia. babesia dna was detected by hemi-nested pcr based on the 18s rrna gene with subsequent direct sequencing. all of the analyzed canine blood samples and three d. reticulatus, but none from i. persulcatus ticks studied were shown to contain babesia dna. nucleotide sequences of the babesia 18s rrna gene fragment ...200516187898
comparison of virulence of coxiella burnetii isolates from bovine milk and from ticks.laboratory animals (mice and guinea pigs) were infected with the isolates of coxiella burnetii (derrick, 1939) obtained from bovine milk (m18 and m35) and the ticks ixodes ricinus (linnaeus, 1758) and dermacentor marginatus (sulzer, 1776) (kl3 and kl6, respectively), and with the reference strain nine mile. neither mortality nor lethality occurred with the mice. antibody response in mice infected with isolates from milk was lower (1:16-512) than that from ticks (1:32-4096). onset of seropositivi ...200111699660
species composition, distribution, and ecological preferences of the ticks of grazing sheep in north-central spain.the distribution and ecological preferences of tick (acari: ixodidae) parasites of grazing sheep in the region of aragón (north-central spain) were surveyed on flocks four times a year and mapped into a 5 x 5 km grid. nine tick species were found. these were species of the rhipicephalus sanguineus group (about 95% of them rhipicephalus turanicus pomerantsev, in 91% of cells of the grid), rhipicephalus bursa canestrini & fanzago (79% of cells), dermacentor marginatus (sulzer) (58% of cells), haem ...200415189237
[analysis of the incidence of tularemia in the breclav district 1994-1999].southern moravia is one of the areas where there are long-term natural foci of tularaemia. in 1994 in the breclav district an exacerbation of the disease was recorded in hares. during autumn hunts a positive reaction was recorded in 5.75% of examined hares. an elevated seropositivity persisted also in subsequent years and at the same time a higher human morbidity in the mentioned region. the objective of the investigation was to assess the causes and circumstances which led to the exacerbation o ...200111233673
infection with a proposed new subspecies of babesia canis, babesia canis subsp. presentii, in domestic cats.parasitemia with a large babesia species was identified in two domestic cats from israel. one cat, also coinfected with feline immunodeficiency virus and "candidatus mycoplasma haemominutum," had profound icterus and anemia which resolved after therapy, whereas a second cat was an asymptomatic carrier. amplification and sequencing of the 18s rrna gene, followed by phylogenetic analyses, indicated that infection was caused by babesia canis. however, the sequences of the internal transcribed and 5 ...200414715738
the ixodid tick species attaching to domestic dogs and cats in great britain and ireland.the species of ixodid ticks, attached to dogs and cats presented to veterinary practices in great britain and ireland were identified. most host animals carried only one tick species with ixodes ricinus linné (acari: ixodidae) being the most common, identified on 52% of animals, ixodes hexagonus leach (acari: ixodidae) the second most common (on 39%) and ixodes canisuga johnston (acari: ixodidae) the third most common (on 11%). a significantly higher proportion of dogs than cats carried i. ricin ...200011016442
[importation of parasites by tourism and animal trading].international transport of animals is associated with an enhanced risk of import of a number of parasite species that are not endemic in germany. pets accompany tourists on journeys all over the world, but in particular to southern europe, and dogs are increasingly imported from (sub-)tropical countries for reasons of animal welfare. veterinary practitioners are thus confronted with parasites that are unusual in their patients. the specific transmission routes determine whether an imported paras ...200111560118
heterogeneity in the effect of different ixodid tick species on human natural killer cell activity.tick saliva plays a vital role in blood-feeding, including manipulation of the host response to tick infestation. furthermore, a diverse number of tick-borne pathogens are transmitted to vertebrate hosts via tick saliva, some of which exploit the immunomodulatory activities of their vector's saliva. we report that salivary gland extracts (sge) derived from dermacentor reticulatus adult ticks induce a decrease in the natural killer (nk) activity of effector cells obtained from healthy human blood ...200211856443
prevalence of borreliae in ixodid ticks from a floodplain forest ecosystem.host-seeking ixodid ticks were sampled in a floodplain forest ecosystem along the lower reaches of the thaya (dyje) river in south moravia (czech republic) and lower austria during the period 1989-2002. the ticks were examined by dark-field microscopy for borreliae (borrelia burgdorferi sensu lato, the agent of lyme borreliosis), and attempts were made to culture the spirochetes in bsk-h medium from preparations containing their high numbers. isolated borreliae were identified by pcr-rflp analys ...200312674689
tularemia.francisella tularensis is the etiological agent of tularemia, a serious and occasionally fatal disease of humans and animals. in humans, ulceroglandular tularemia is the most common form of the disease and is usually a consequence of a bite from an arthropod vector which has previously fed on an infected animal. the pneumonic form of the disease occurs rarely but is the likely form of the disease should this bacterium be used as a bioterrorism agent. the diagnosis of disease is not straightforwa ...200212364373
distinct combinations of borrelia burgdorferi sensu lato genospecies found in individual questing ticks from europe.the genetic diversity of borrelia burgdorferi sensu lato was assessed in individual adult ixodes ricinus ticks from europe by direct pcr amplification of spirochetal dna followed by genospecies-specific hybridization. analysis of mixed infections in the ticks showed that b. garinii and b. valaisiana segregate from b. afzelii. this and previous findings suggest that host complement interacts with spirochetes in the tick, thereby playing an important role in the ecology of lyme borreliosis.200111571205
effect of the salivary gland and midgut extracts from ixodes ricinus and dermacentor reticulatus (acari: ixodidae) on the growth of borrelia garinii in vitro. 200314560980
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
[results of the 20-year study of tick-borne encephalitis in crimea].the history of tick-borne encephalitis (tbe) study in the crimea was retraced and the possibility of introduction of tbe virus to the crimea in the process of the acclimatization of vertebrates from areas enzootic for tbe is discussed. the foci of tbe were found throughout the whole of the mountain forest zone of the crimea and coincided with the habitat area of lxodes ricinus, the main vector of tbe. such ticks as dermacentor reticulatus, d. marginatus and hyalomma marginatum were also found to ...200111548243
spatial distribution of dermacentor reticulatus and ixodes ricinus in hungary: evidence for change?a survey was conducted to investigate the spatial distribution of ixodes ricinus and dermacentor reticulatus in hungary and to compare these data with the results of a previous large-scale survey. in the survey conducted in the 1950s, d. reticulatus adults were detected in two isolated areas of two counties, and the presence of these ticks in the collection was explained by accidental introduction. in the present survey, d. reticulatus became the second most common species occurring in all 16 co ...200515740873
host-seeking activity of ixodid ticks in relation to weather variables.ixodid ticks were monitored in a temperate deciduous broad-leaved forest in south moravia (czech republic). relative abundance of the ticks collected before noon (10.00-12.00 h) was compared to several weather variables (air and soil temperatures, relative humidity, precipitation, wind speed, and derived values) using the pearson correlation coefficient. the tick numbers were found to be most closely related to the amplitude of the soil (-5 cm) temperature between 07 h and 14 h (tsamp, in ixodes ...200314714663
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