detection of rickettsia sibirica in ticks and small mammals collected in three different regions of china.the primers rr 190.70p and rr 190.602n were used to detect spotted fever group (sfg) rickettsiae by polymerase chain reaction (pcr) in ticks and small mammals collected in three different regions of china. the obtained results indicated that specific dna fragments of sfg rickettsiae were amplified from dermacentor silvarum, d. sinicus, d. auratus, haemaphysalis concinna, h. wellingtoni, h. yeni, apodemus agrarius, microtus fortis. clethrionomys rufocanus, ondatra zibethica, rattus flavipectus an ...19989645245
[detection of north-asia tick-borne spotted fever in ticks and rodents along the heilongjiang river-side by restriction fragment length polymorphism of pcr products].in order to elucidate the natural foci of north-asia tick-borne spotted fever along the bank of heilongjiang river, we used pcr/rflp to detect spotted fever group rickettsiae in ticks and rodents. the results showed that the wild samples of dermacentor silvarum, haemaphysalis concinna and apodemus agrarius, microtus fortis, clethrionomys rufocanus and ondatra zibethica were all positive with amplification, but typhus rickettsiae, tsutsugamushi fever rickettsiae and q fever rickettsiae were all n ...19979812471
[isolation of a novel rickettsia from the tick dermacentor silvarum in baikal lake region].a new species of rickettsiae with unknown pathogenicity has been detected in ticks dermacentor silvarum in the region of baikal lake. as revealed by the analysis of the primary structure of the gene fragment coding surface membrane protein of 190 kd (rompa), the nucleotide sequence of the rickettsiae under study is mostly similar to the sequences of r. sp. moaa isolate (96%), r. sp. wb-8-2 (96%), r. massiliae strain gs (94%), rickettsia bar-29 (94%), r. rhipicephali (94%). similarity with the se ...200111871312
gene sequence-based criteria for identification of new rickettsia isolates and description of rickettsia heilongjiangensis sp. nov.we propose genetic guidelines for the classification of rickettsial isolates at the genus, group, and species levels by using sequences of the 16s rrna (rrs) gene and four protein-coding genes, the glta, ompa, and ompb genes and gene d. to be classified as a member of the genus rickettsia, an isolate should exhibit degrees of rrs and glta homology with any of the 20 rickettsia species studied of >/=98.1 and >/=86.5%, respectively. a member of the typhus group should fulfill at least two of the f ...200314662925
tick-borne rickettsioses around the world: emerging diseases challenging old concepts.during most of the 20th century, the epidemiology of tick-borne rickettsioses could be summarized as the occurrence of a single pathogenic rickettsia on each continent. an element of this paradigm suggested that the many other characterized and noncharacterized rickettsiae isolated from ticks were not pathogenic to humans. in this context, it was considered that relatively few tick-borne rickettsiae caused human disease. this concept was modified extensively from 1984 through 2005 by the identif ...200516223955
novel rickettsia in ticks, tasmania, australia.a novel rickettsia was detected in ixodes tasmani ticks collected from tasmanian devils. a total of 55% were positive for the citrate synthase gene by quantitative pcr. according to current criteria for rickettsia speciation, this new rickettsia qualifies as candidatus rickettsia tasmanensis, named after the location of its detection.200919861066
the life cycle and biological characteristics of dermacentor silvarum olenev (acari: ixodidae) under field this study, we investigated the life cycle and biological characteristics of all developmental stages of dermacentor silvarum under field conditions in hebei province in north china. larvae, nymphs and adults were fed on rabbits, and maintained under natural lighting and climate conditions. ticks were released into a confined plot located in natural tick habitat, and we observed the host questing behavior and seasonal occurrence. due to a behavioral diapause in females and the synchronization ...201020006442
tick-borne agents in rodents, china, 2004-2006.a total of 705 rodents from 6 provinces and autonomous regions of mainland people's republic of china were tested by pcrs for tick-borne agents (anaplasma phagocytophilum, borrelia burgdorferi sensu lato, spotted fever group rickettsiae, and francisella tularensis). infection rates were 5.5%, 6.7%, 9.1% and 5.0%, respectively. eighteen (2.6%) rodents of 10 species were positive for 2 or 3 agents. sequence analysis of pcr products confirmed the presence and genotypes of detected agents. these fin ...200919961668
molecular epidemiology of powassan virus in north america.powassan virus (pow) is a tick-borne flavivirus distributed in canada, the northern usa and the primorsky region of russia. pow is the only tick-borne flavivirus endemic to the western hemisphere, where it is transmitted mainly between ixodes cookei and groundhogs (marmota monax). deer tick virus (dtv), a genotype of pow that has been frequently isolated from deer ticks (ixodes scapularis), appears to be maintained in an enzootic cycle between these ticks and white-footed mice (peromyscus leucop ...201020631087
detection of francisella tularensis in ticks and identification of their genotypes using multiple-locus variable-number tandem repeat analysis.tularemia was reported in china over 50 years ago, however, many epidemical characteristics remain unclear. in the present study, the prevalence of francisella tularensis in ticks was investigated during an epidemiological surveillance in china and then we measured their genetic diversity by conducting multiple-locus variable- number tandem repeat analysis (mlva).200818798995
molecular detection of spotted fever group rickettsia in dermacentor silvarum from a forest area of northeastern total, 676 dermacentor silvarum olenev (acari: ixodidae) from a forest area of jilin province in northeastern china were examined by polymerase chain reaction for the presence of spotted fever group (sfg) rickettsia. the overall positive rate was 10.7%, with a 95% confidence interval from 8.3 to 13.0%. the sfg rickettsia infection was more prevalent in adults than in nymphs, and in fed ticks obtained from domestic animals than in those collected on vegetation. sequence analysis of the partial ...200818714877
rickettsia raoultii sp. nov., a spotted fever group rickettsia associated with dermacentor ticks in europe and russia.we describe the characterization of a novel rickettsia species cultivated from dermacentor ticks collected in russia and france, for which we propose the name rickettsia raoultii sp. nov. using multigene sequencing, we demonstrated that five rickettsial isolates from dermacentor silvarum, dermacentor reticulatus, dermacentor marginatus and dermacentor nuttalli ticks were classified within this novel spotted fever rickettsia species. this rickettsia also exhibited a serotype distinct from previou ...200818599708
status of haemaphysalis tick infestation in domestic ruminants in iran.the geographical distribution and ecological preferences of haemaphysalis in domestic animals in iran were studied 4 times a year from april 2003 to march 2005. a total of 1,622 ixodid tick specimens were collected from 3 different zones. among them, 108 (6.7%) haemaphysalis ticks, consisting of 6 species, were identified; h. punctata (3.4%), h. parva (0.5%), h. sulcata (0.6%), h. choldokovskyi (1.7%), h. concinna (0.06%) and haemaphysalis sp. (0.6%). h. punctata was the most abundant species, w ...200717570976
natural anaplasma phagocytophilum infection of ticks and rodents from a forest area of jilin province, china.polymerase chain reaction integrated with sequence analysis was carried out to investigate the natural anaplasma phagocytophilum infection in ticks and rodents from a forest area of jilin province, china. four (4.0%) of 100 ixodes persulcatus and 2 (0.7%) of 286 dermacentor silvarum ticks collected by flagging vegetation were positive. nine (8.8%) of 102 rodents were infected, as well as 2 (2.8%) of 71 i. persulcatus parasitizing on 25 rodents. the nucleotide sequences of 1442-bp a. phagocytophi ...200617038691
genetic differentiation of chinese isolates of rickettsia sibirica by partial ompa gene sequencing and multispacer typing.current data on rickettsiae and rickettsial diseases in china remain limited. using partial ompa gene sequencing and multispacer typing, we identified 15 rickettsial isolates from china. all isolates were found to belong to rickettsia sibirica subsp. sibirica. four isolates from dermacentor sinicus collected in beijing, china, were fully identical to strain bj-90, previously demonstrated to belong to r. sibirica subsp. sibirica despite antigenic and genotypic specificities. all 11 remaining isol ...200616825365
bioinformatics and expression analyses of the ixodes scapularis tick cystatin family.the cystatins are inhibitors of papain- and legumain-like cysteine proteinases, classified in merops subfamilies i25a-i25c. this study shows that 84 % (42/50) of tick cystatins are putatively extracellular in subfamily i25b and the rest are putatively intracellular in subfamily i25a. on the neighbor joining phylogeny guide tree, subfamily i25a members cluster together, while subfamily i25b cystatins segregate among prostriata or metastriata ticks. two ixodes scapularis cystatins, aay66864 and is ...201223053911
coxiella burnetii genotyping.coxiella burnetii is a strict intracellular bacterium with potential as a bioterrorism agent. to characterize different isolates of c. burnetii at the molecular level, we performed multispacer sequence typing (mst). mst is based on intergenic region sequencing. these regions are potentially variable since they are subject to lower selection pressure than the adjacent genes. we screened 68 spacers in 14 isolates and selected the 10 that exhibited the most variation. these spacers were then tested ...200516102309
revisiting the clinal concept of evolution and dispersal for the tick-borne flaviviruses by using phylogenetic and biogeographic analyses.tick-borne flaviviruses (tbf) are widely dispersed across africa, europe, asia, oceania, and north america, and some present a significant threat to human health. seminal studies on tick-borne encephalitis viruses (tbev), based on partial envelope gene sequences, predicted a westward clinal pattern of evolution and dispersal across northern eurasia, terminating in the british isles. we tested this hypothesis using all available full-length open reading frame (orf) tbf sequences. phylogenetic ana ...201222674986
microbial communities and symbionts in the hard tick haemaphysalis longicornis (acari: ixodidae) from north china.close relationships between ticks and microbial communities are important for tick fitness and pathogen colonization and transmission. haemaphysalis longicornis, distributed widely in china, can carry and transmit various pathogens and pose serious damages to public health and economics. however, little is known about the broader array of microbial communities and symbionts in h. longicornis under natural conditions. in the present study, we investigated the composition of bacterial communities ...201324499619
biology of dermacentor silvarum (acari: ixodidae) under laboratory conditions.the minimum life cycle of dermacentor silvarum olenev had a mean duration of 87.5 days (range 74-102 days) under laboratory conditions [(27 +/- 1 degrees c), 70% rh, 6 l: 18 d]. the mean time in (days) for the different stages of its cycle was as follows: incubation period of eggs was 15.3 days; prefeeding, feeding and premoulting periods of larvae and nymphs averaged 5.5, 4.0 and 7.3 days, and 5.2, 5.0 and 14.6 days, respectively; prefeeding, feeding, preoviposition and oviposition periods of f ...200516082930
a 24-48 h fed amblyomma americanum tick saliva immuno-proteome.multiple tick saliva proteins, the majority of which are unknown, confer tick resistance in repeatedly infested animals. the objective of this study was to identify the 24-48 h fed amblyomma americanum tick saliva immuno-proteome. the 24-48 h tick-feeding phase is critical to tick parasitism as it precedes important events in tick biology, blood meal feeding and disease agent transmission. fed male, 24 and 96 h fed female phage display cdna expression libraries were biopanned using rabbit antibo ...201424962723
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
ability of ixodes persulcatus, haemaphysalis concinna and dermacentor silvarum ticks to acquire and transstadially transmit borrelia china, the ability of ixodes persulcatus, haemaphysalis concinna and dermacentor silvarum to transmit borrelia spirochetes was determined under laboratory conditions. results showed that all three tick species can acquire spirochetes by feeding on infected mice. however, the capability of the three species to maintain spirochetes was different. only i. persulcatus is able to maintain spirochetes alive during molting, and subsequent tick stages transmitted the infection to naive mice. in h. co ...200314756409
ehrlichiae and ehrlichial diseases in china.the various ticks collected from different areas of china were examined for the existence of ehrlichial agents by polymerase chain reaction (pcr) with genus- or species-specific primers designed on the basis of ehrlichial 16s rrna genes and sequence analyses. in southern china, e. chaffeensis was detected in amblyomma testudinarium ticks from infested cattle, haemaphysalis yeni ticks from hare, and ixodes ovatus ticks from muntiacus reevesi. e. canis was identified in rhipicephalus sanguineus ti ...200312860598
genetic identification of rickettsiae isolated from ticks in japan.following the description in japan of japanese spotted fever, caused by rickettsia japonica, a search for the vector of this disease led to the isolation of several rickettsiae from various tick species. sixty-three rickettsial isolates were obtained from six different tick species, and six type strains were described by pcr and monoclonal antibody testing. we identified these six strains by amplification and sequencing of the genes encoding 16s rrna and citrate synthase. we confirmed that the i ...200212037083
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
genetic classification of "rickettsia heilongjiangii" and "rickettsia hulinii," two chinese spotted fever group determine the phylogenetic position of two new rickettsial strains isolated from ticks in china, 16s ribosomal dna, glta, and ompa (apart from the tandem repeat units) genes were amplified by pcr and sequenced. the phylogenetic relationships between these strains and other rickettsiae were inferred from the comparison of sequences of the three genes by the parsimony, neighbor-joining, and maximum-likelihood methods. the results demonstrated that the 054 strain, a rickettsia pathogenic in huma ...200010970415
[investigation on primary vectors of borrelia burgdorferi in china].from 1987 to 1997, primary vectors of borrelia burgdorferi sensu lato (b.b.s.l.) were investigated in china. a total number of 17,000 ticks collected from 20 provinces, city and autonomous region were classified, including 2 families 8 genus 23 species. there were 108 isolates of b.b.s.l. discovered from 8 species of ticks, including ixodes persulcatus, i. granulatus, i. acutitarsus, haemaphysalis concinna, h. longicornis, h. bispinosis, h. cornigera taiwana and dermacentor silvarum. ixodes pers ...199810322682
detection of borrelia burgdorferi from ticks (acari) in hebei province, china.from may 1992 to august 1993, 1,196 ticks were collected by flagging vegetation and from domestic animals in chengde, zhangjiakou, shijiazhuang, and handan districts of hebei province. of those ticks collected, 954 were haemaphysalis japonicum warburton and h. longicornis neumann, 205 were ixodes persulcatus schulze, and 37 were dermacentor silvarum olenev. four strains of borrelia burgdorferi were isolated from 135 i. persulcatus collected in weichang and zhuolu counties. three of 574 haemaphys ...19989538567
[range of the tick dermacentor silvarum in the ussr]. 19836888330
[reproductive characteristics of the tick-borne encephalitis and powassan viruses in dermacentor silvarum imago explants removed from the nymphal cuticle]. 19816268959
update on tick-borne rickettsioses around the world: a geographic approach.tick-borne rickettsioses are caused by obligate intracellular bacteria belonging to the spotted fever group of the genus rickettsia. these zoonoses are among the oldest known vector-borne diseases. however, in the past 25 years, the scope and importance of the recognized tick-associated rickettsial pathogens have increased dramatically, making this complex of diseases an ideal paradigm for the understanding of emerging and reemerging infections. several species of tick-borne rickettsiae that wer ...024092850
[development of a lesion in ixodid ticks (ixodes persulcatus, dermacentor silvarum, haemaphysalis concinna) following the action of ddt]. 19744419643
anaplasma phagocytophilum--a widespread multi-host pathogen with highly adaptive strategies.the bacterium anaplasma phagocytophilum has for decades been known to cause the disease tick-borne fever (tbf) in domestic ruminants in ixodes ricinus-infested areas in northern europe. in recent years, the bacterium has been found associated with ixodes-tick species more or less worldwide on the northern hemisphere. a. phagocytophilum has a broad host range and may cause severe disease in several mammalian species, including humans. however, the clinical symptoms vary from subclinical to fatal ...201323885337
[characteristics of the transphase and transovarial transmission of rickettsia sibirica by ixodid and argasid ticks].both the specific vector dermacentor silvarum and the nonspecific one ornithodoros papillipes are shown to become rickettsia sibirica infected while sucking blood on the infected guinea pigs. meanwhile, the specific vector d. silvarum is more sensitive to r. sibirica than the nonspecific. o papillipes. the infectivity of d. silvarum and o. papillipes ticks by r. sibirica was found to be dependent on the intensity of guinea pigs' rickettsemia. transovarial transmission of rickettsia has been esta ...19892811744
[ecology of the tick, dermacentor silvarum o1].results of the experiments have shown that the development of dermacentor silvarum from egg to imago varied from 44 to 46 days at 28 c and redundant humidity and from 50 to 52 days at 25 degrees c. the thermic threshold of larval development lies within a range of 8.6 degrees c, that of nymphs-9.7 degrees c. a sum of effective temperatures required for larval development averaged 123.5 degrees c, for nymphs-225 degrees c and for the whole ontogenesis-from 570 to 690 degrees c. in the north of th ...19751221338
molecular characterization of a defensin gene from a hard tick, dermacentor silvarum.ticks are distributed worldwide and considered as vectors of many human diseases. tick defensins, a family of antimicrobial peptides, form the first line of defense against pathogens.201525588982
arsenophonus nasoniae and rickettsiae infection of ixodes ricinus due to parasitic wasp ixodiphagus hookeri.arsenophonus nasoniae, a male-killing endosymbiont of chalcid wasps, was recently detected in several hard tick species. following the hypothesis that its presence in ticks may not be linked to the direct occurrence of bacteria in tick's organs, we identified a. nasoniae in wasps emerging from parasitised nymphs. we confirmed that 28.1% of ixodiphagus hookeri wasps parasitizing ixodes ricinus ticks were infected by a. nasoniae. moreover, in examined i. ricinus nymphs, a. nasoniae was detected on ...201626901622
nairobi sheep disease virus rna in ixodid ticks, china, 2013. 025811222
[ability of female ixodid ticks to recover from poisoning with ddt in the process of feeding].ability of hungary females of ixodes persulcatus, haemaphysalis concinna and dermacentor silvarum to feed and lay eggs after having been exposed to different ddt doses (ld100) has been studied. the ticks heavily injuried but still mobile can feed on the host and lay eggs, i.e. to overcome the poisoning. clutches laid by these females do not differ from control ones. loss of mobility deprives the ticks of the ability to fed. an increase in ddt dose (ld100 x 100, experiment with i. persulcatus) do ...19751187171
[sublethal action and aftereffect of ddt on dermacentor silvarum 01. (acarina, ixodidae)].observations were conducted on the processes of feeding and oviposition in the females of dermacentor silvarum poisoned with ddt, the ancestors of which had been subjected to this acaricide and had overcome the poisoning due to the feeding. the rise in the sensitivity to ddt in the females of the second generation and a number of pathological changes both in feeding females and in their progeny were noted.1976958715
coinfection of dermacentor silvarum olenev (acari: ixodidae) by coxiella-like, arsenophonus-like, and rickettsia-like symbionts.we report that multiple symbionts coexist in dermacentor silvarum. based on 16s rrna gene sequence analyses, we prove that coxiella-like and arsenophonus-like symbionts, with 95.6% and 96.7% sequence similarity to symbionts in the closest taxon, respectively, are novel. moreover, we also provide evidence that the coxiella-like symbiont appears to be the primary symbiont.201323354701
[sensitivity of the females of ixodes persulcatus and dermacentor silvarum (ixodidae) to baytex and the possibility of their overcoming poisoning with this substance].females of i. persulcatus and d. silvarum are very sensitive to baytex, the value of ld50 for both species are similar. the development of injury after exposure to baytex proceeds very quickly and the subsequent stages of injury development correspond to those caused by ddt (uspensky and levikov, 1974). the overcoming of baytex poisoning during the sucking of the host's blood is possible only at the initial stage of the injury. the simulatneous feeding on the same rabbit of ticks treated with ba ...1977896262
molecular detection and characterization of anaplasma spp. in sheep and cattle from xinjiang, northwest china.anaplasmosis is caused by obligate intracellular bacteria in the genus anaplasma. these bacterial pathogens are transmitted by ticks and impact both human and animal health. this study was conducted to determine the prevalence and molecular characterization of anaplasma spp. in ruminants sampled in xinjiang, northwest china.201525889906
[detection of babesia spp. dna in small mammals and ixodic ticks on the territory of north ural, west siberia and far east of russia].totally, 932 small mammals and 458 questing adult ixodes persulcatus from sverdlovsk and novosibirsk regions and khabarovsk territory, as well as 128 haemaphysalis japonica, 34 h. concinna and 29 dermacentor silvarum from khabarovsk territory were examined for the presence of babesia by nested pcr based on the 18s rrna gene. babesia microti dna was found in samples of small mammals from all the studied regions--in 36.2% of samples from sverdlovsk region, 5.3% of samples from novosibirsk region, ...201020886686
human infection with candidatus neoehrlichia mikurensis, identify candidatus neoehrlichia mikurensis infection in northeastern china, we tested blood samples from 622 febrile patients. we identified in 7 infected patients and natural foci for this bacterium. field surveys showed that 1.6% of ticks and 3.8% of rodents collected from residences of patients were also infected.201223017728
distribution of tick-borne diseases in an important contributor to vector-borne diseases in china, in recent years, tick-borne diseases have attracted much attention because of their increasing incidence and consequent significant harm to livestock and human health. the most commonly observed human tick-borne diseases in china include lyme borreliosis (known as lyme disease in china), tick-borne encephalitis (known as forest encephalitis in china), crimean-congo hemorrhagic fever (known as xinjiang hemorrhagic fever in china), q-f ...201323617899
origin and evolution of rickettsial plasmids.rickettsia species are strictly intracellular bacteria that have undergone a reductive genomic evolution. despite their allopatric lifestyle, almost half of the 26 currently validated rickettsia species have plasmids. in order to study the origin, evolutionary history and putative roles of rickettsial plasmids, we investigated the evolutionary processes that have shaped 20 plasmids belonging to 11 species, using comparative genomics and phylogenetic analysis between rickettsial, microbial and no ...201626866478
prevalence and genetic characterization of powassan virus strains infecting ixodes scapularis in connecticut.a total of 30 powassan virus (powv) isolates from ixodes scapularis collected from bridgeport and north branford, ct in 2008, 2010, 2011, and 2012 and one earlier isolate from ixodes cookei collected in old lyme, ct in 1978 were characterized by phylogenetic analysis of their envelope gene sequences. powassan virus sequences segregated into two major groups termed the deer tick virus (dtv) and powassan (pow) lineages. the lineage from i. cookei was pow. the remaining viruses from i. scapularis g ...201222890037
the diversity and prevalence of hard ticks attacking human hosts in eastern siberia (russian federation) with first description of invasion of non-endemic tick species.hard ticks are the vectors of many pathogens including tick-borne encephalitis virus and the lyme disease agent borrelia burgdorferi sensu lato. in eastern siberia, ixodes persulcatus, dermacentor nuttalli, dermacentor silvarum and haemaphysalis concinna are regarded as aggressive to humans. recently, significant changes in world tick fauna have been reported and this affects the spread of tick-borne pathogens. we studied the current species diversity, population structure and prevalence of tick ...201626443685
anaplasma phagocytophilum infection in domestic animals in ten provinces/cities of china.a nationwide epidemiologic investigation of domestic animal infections has been conducted in nine provinces and one city during 2007-2010. serum samples from a total of 707 goats, 433 cattle, and 219 dogs were collected for detecting anaplasma phagocytophilum igg antibody by immunofluorescence assays and the average seroprevalences were 10.05% for dogs, 3.82% for goats, and 0.69% for cattle, respectively. a total of 472 goats, 201 cattle, 102 dog blood clots, and 1,580 ticks were collected for p ...022764312
seasonal abundance and activity of the tick dermacentor silvarum in northern china.studies on the seasonal abundance and activity of larvae, nymphs and adults of dermacentor silvarum (ixodida: ixodidae), both on and off the host, were carried out over a 2-year period from february 2008 to january 2010 in northern china. during the study period, feeding ticks were removed weekly from domestic sheep and free-living ticks were collected weekly by flag-dragging in four different habitat types. rodents were captured and inspected for immature ticks from june to september 2008. the ...201020969606
serologic evidence for babesia bigemina infection in wild yak (bos mutus) in qinghai province, china.piroplasmosis, caused by tick-borne protozoan parasites of the genera theileria and babesia, is one of the most economically important infections of domestic ruminants in china. we evaluated the prevalence of antibodies to babesia bigemina in wild yaks (bos mutus) from qinghai province, china. of 91 samples, 24% had detectable b. bigemina antibodies, and significant differences in prevalence were observed between those older than 5 yr and those younger than 5 yr. we collected 1,679 ticks belongi ...201526267460
genetic variability of babesia parasites in haemaphysalis spp. and ixodes persulcatus ticks in the baikal region and far east of study babesia diversity in ixodid ticks in russia, ixodes persulcatus, haemaphysalis japonica, haemaphysalisconcinna, dermacentor silvarum, and dermacentor nuttalli ticks collected in the far east and baikal region were assayed for the presence of babesia spp. using nested pcr. in total, babesia dna was detected in 30 of the 1125 (2.7%) i. persulcatus, 17 of the 573 (3.0%) h. concinna, and 12 of the 543 (2.2%) h. japonica but was undetectable in any of the 294 analyzed dermacentor spp. partia ...201425460820
molecular detection of anaplasma spp. and ehrlichia spp. in ruminants from twelve provinces of china.anaplasma spp. and ehrlichia spp. are tick-transmitted bacteria that are of significant economic importance as they can infect large and small ruminants and also people. there is little information on anaplasmosis and ehrlichiosis in ruminants in china. 16s rrna fret-qpcrs were used to screen convenience whole blood samples from 2,240 domestic ruminants in 12 provinces of china for anaplasma spp. and ehrlichia spp. positive samples were further analyzed with a standard pcr for the glta. anaplasm ...201628096822
molecular detection and characterization of zoonotic and veterinary pathogens in ticks from northeastern china.tick-borne diseases are considered as emerging infectious diseases in humans and animals in china. in this study, ixodes persulcatus (n = 1699), haemaphysalis concinna (n = 412), haemaphysalis longicornis (n = 390), dermacentor nuttalli (n = 253), and dermacentor silvarum (n = 204) ticks were collected by flagging from northeastern china, and detected for infection with anaplasma, ehrlichia, babesia, and hepatozoon spp. by using nested polymerase chain reaction assays and sequencing analysis. an ...201627965644
characterization of rickettsiae in ticks in northeastern china.tick-borne rickettsioses are considered important emerging zoonoses worldwide, but their etiological agents, rickettsiae, remain poorly characterized in northeastern china, where many human cases have been reported during the past several years. here, we determined the characteristics of rickettsia spp. infections in ticks in this area.201627623998
genome sequence of the tick-borne pathogen rickettsia raoultii.italic! rickettsia raoultiiis a tick-associated spotted fever group (sfg) organism, causing scalp eschar and neck lymphadenopathy after tick bite (senlat) in humans. we report here the genome sequence of italic! r. raoultiistrain khabarovsk(t)(csur r3(t), atcc vr-1596(t)), which was isolated from a italic! dermacentor silvarumtick collected in russia.201627103706
rural residents in china are at increased risk of exposure to tick-borne pathogens anaplasma phagocytophilum and ehrlichia emerging tick born rickettsial diseases caused by a. phagocytophilum and e. chaffeensis, anaplasmosis and ehrlichiosis have become a serious threat to human and animal health throughout the world. in particular, in china, an unusual transmission of nosocomial cases of human granulocytic anaplasmosis occurred in anhui province in 2006 and more recent coinfection case of a. phagocytophilum and e. chaffeensis was documented in shandong province. although the seroprevalence of human granulocytic ...201424877080
sensitivity to permethrin in a dermacentor reticulatus population from eastern poland in laboratory study.the action of chemical compounds on the palaearctic tick d. reticulatus (fabricius) (acari: amblyomminae) has been poorly investigated so far. therefore, the effects of application of permethrin on engorged d. reticulatus females have been assessed, and the survival rate for the different developmental stages of the tick species in its non-parasitic phase of the life cycle was determined upon application of the pyrethroid.201424405550
cloning and molecular analysis of voraxin-α gene of rhipicephalus (boophilus) identify suitable targets for development of cross-protective tick vaccine, in silico analysis was attempted and male tick derived molecule, voraxin-α was targeted. the voraxin-α homologue of rhipicephalus (boophilus) microplus was cloned, sequenced and analyzed employing standard methods. the deduced amino acids sequence analysis of the 419 bp cloned voraxin-α gene of r. (b.) microplus indicated very high (94.6 %) similarity with voraxin-α of the r. appendiculatus and moderate to low identit ...201627065622
proteome analysis and serological characterization of surface-exposed proteins of rickettsia heilongjiangensis.rickettsia heilongjiangensis, the agent of far-eastern spotted fever (fesf), is an obligate intracellular bacterium. the surface-exposed proteins (seps) of rickettsiae are involved in rickettsial adherence to and invasion of host cells, intracellular bacterial growth, and/or interaction with immune cells. they are also potential molecular candidates for the development of diagnostic reagents and vaccines against rickettsiosis.201323894656
[molecular epidemiology regarding anaplasma phagocytophilum in dermacentor silvarum in ningwu county, shanxi province]. 201222993783
rickettsia raoultii, the predominant rickettsia found in dermacentor silvarum ticks in china-russia border areas.since the year 2000, clinical patterns resembling tick-borne rickettsioses have been noticed in china-russia border areas. epidemiological data regarding species of the aetiological agent, tick vector prevalence and distribution as well as incidence of human cases in the areas are still sparse to date. in order to identify rickettsia species occurring in the areas, we investigated dermacentor silvarum collected in the selected areas. rickettsia raoultii was the predominant rickettsia found in d. ...201424699771
detection and differentiation of borrelia burgdorferi sensu lato in ticks collected from sheep and cattle in china.abstract:201121529349
anaplasma phagocytophilum infection in ticks, china-russia the editor: anaplasma phagocytophilum, an emerging human pathogen of public health importance, is transmitted to humans most commonly by tick bites (1). the agent has been detected in various species of ixodes ticks around the world (2) and in dermacentor silvarum ticks in northeastern people's republic of china (3), where 3 a. phagocytophilum strains were isolated from wild and domestic animals (4). in the asiatic region of russia adjacent to china, a. phagocytophilum was identified in ixode ...201121529418
genetic diversity of anaplasma and ehrlichia in the asian part of russia.totally, 2590 questing adult ixodes persulcatus ticks and 1458 small mammals from ural, siberia, and the far east as well as 53 haemaphysalis concinna, 136 haem. japonica, and 43 dermacentor silvarum ticks--exclusively adults--from the far east were examined for the presence of ehrlichia and anaplasma by nested pcr based on the 16s rrna gene. both anaplasma phagocytophilum and ehrlichia muris were found in i. persulcatus and small mammals from all the studied regions. myodes spp., microtus spp., ...201021771512
first report on the occurrence of rickettsia slovaca and rickettsia raoultii in dermacentor silvarum in china.abstract: background: rickettsioses are among both the longest known and most recently recognized infectious diseases. although new spotted fever group rickettsiae have been isolated in many parts of the world including china, little is known about the epidemiology of rickettsia pathogens in ticks from xinjiang autonomous region of china. methods: in an attempt to assess the potential risk of rickettsial infection after exposure to ticks in xinjiang uygur autonomous region of china, a total of ...201222257726
emerging tick-borne infections in mainland china: an increasing public health threat.since the beginning of the 1980s, 33 emerging tick-borne agents have been identified in mainland china, including eight species of spotted fever group rickettsiae, seven species in the family anaplasmataceae, six genospecies in the complex borrelia burgdorferi sensu lato, 11 species of babesia, and the virus causing severe fever with thrombocytopenia syndrome. in this review we have mapped the geographical distributions of human cases of infection. 15 of the 33 emerging tick-borne agents have be ...201526453241
genetic diversity and molecular characterization of babesia motasi-like in small ruminants and ixodid ticks from china.ovine babesioses, an important tick-borne disease of sheep and goats in china, is caused by the reproduction of intraerythrocytic protozoa of the babesia genus. babesia motasi-like is a babesia parasite that infects small ruminant in china, and two sub-groups of b. motasi-like can be subdivided based on differences in the rhoptry-associated-protein-1 gene. this study aimed to characterize the distribution, epidemiology and genetics of b. motasi-like in animals and ticks. a molecular investigatio ...201626976477
human infections with rickettsia raoultii, china.we used molecular methods to identify rickettsia raoultii infections in 2 persons in china. these persons had localized rashes around sites of tick bites. r. raoultii dna was detected in 4% of dermacentor silvarum ticks collected in the same area of china and in 1 feeding tick detached from 1 patient.201424750663
investigation of borrelia spp. in ticks (acari: ixodidae) at the border crossings between china and russia in heilongjiang province, investigate the precise species of tick vector and the borrelia spirochete pathogen at the heilongjiang province international border with russia.201222575978
dissemination of spotted fever rickettsia agents in europe by migrating birds.migratory birds are known to play a role as long-distance vectors for many microorganisms. to investigate whether this is true of rickettsial agents as well, we characterized tick infestation and gathered ticks from 13,260 migratory passerine birds in sweden. a total of 1127 ixodes spp. ticks were removed from these birds and the extracted dna from 957 of them was available for analyses. the dna was assayed for detection of rickettsia spp. using real-time pcr, followed by dna sequencing for spec ...201020052286
[experimental analysis of the seasonal, cyclic adaptations of dermacentor silvarum ol. (acarina, ixodidae)]. 19734777802
complete mitochondrial genomes of dermacentor silvarum and comparative analyses with another hard tick dermacentor nitens.ticks are obligate blood-sucking ectoparasites of a wide range of vertebrates. they can transmit a range of pathogens that cause economic losses to livestock production as well as human disease. in the present study, the complete mitochondrial (mt) genome of dermacentor silvarum was determined. the mt genome is 14,945 bp in length contains 37 genes, including 13 are protein-coding genes (cox1-3, nad1-6, nad4l, cytb, atp6 and atp8), two ribosomal rna genes and 22 transfer rna genes. the nucleotid ...201627423970
population dynamics of multiple symbionts in the hard tick, dermacentor silvarum olenev (acari: ixodidae).previously, we reported that coxiella-like, rickettsia-like and arsenophonus-like symbionts could simultaneously coexist in dermacentor silvarum. in this study, we examined their burdens and population dynamics in a single host during the host life cycle using quantitative pcr. our results showed that multiple symbionts exhibited different abundances and varying trends in the tick host. coxiella-like and rickettsia-like symbionts were found at high densities in large quantities that fluctuated w ...201626565930
detection of spotted fever group rickettsiae in ticks from zhejiang province, china.tick species distribution and prevalence of spotted fever group rickettsiae (sfgr) in ticks were investigated in zhejiang province, china in 2010 and 2011. pcr was used to detect sfgr and positive amplicons were sequenced, compared to published sequences and phylogenic analysis was performed using mega 4.0. a total of 292 adult ticks of ten species were captured and 7.5 % (22/292) of the ticks were pcr-positive for sfg rickettsia. the pcr-positive rates were 5.5 % (6/110) for haemaphysalis longi ...201525633265
screening and identification of antigenic proteins from the hard tick dermacentor silvarum (acari: ixodidae).in order to explore tick proteins as potential targets for further developing vaccine against ticks, the total proteins of unfed female dermacentor silvarum were screened with anti-d. silvarum serum produced from rabbits. the results of western blot showed that 3 antigenic proteins of about 100, 68, and 52 kda were detected by polyclonal antibodies, which means that they probably have immunogenicity. then, unfed female tick proteins were separated by 12% sds-page, and target proteins (100, 68, a ...201526797451
[construction of suppression subtractive hybridization cdna library of half-blood males of dermacentor silvarum and analysis of differentially expressed genes].to construct a suppression subtractive hybridization (ssh) cdna library of half-blood males of dermacentor silvarum, and analyze the differentially expressed genes.201425518590
an efficient strategy of screening for pathogens in wild-caught ticks and mosquitoes by reusing small rna deep sequencing data.this paper explored our hypothesis that srna (18 ∼ 30 bp) deep sequencing technique can be used as an efficient strategy to identify microorganisms other than viruses, such as prokaryotic and eukaryotic pathogens. in the study, the clean reads derived from the srna deep sequencing data of wild-caught ticks and mosquitoes were compared against the ncbi nucleotide collection (non-redundant nt database) using blastn. the blast results were then analyzed with in-house python scripts. an empirical fo ...201424618575
first report of rickettsia raoultii and r. slovaca in melophagus ovinus, the sheep ked.melophagus ovinus (diptera: hippoboscidae), a hematophagous ectoparasite, is mainly found in europe, northwestern africa, and asia. this wingless fly infests sheep, rabbits, and red foxes, and causes inflammation, wool loss and skin damage. furthermore, this parasite has been shown to transmit diseases, and plays a role as a vector. herein, we investigated the presence of various rickettsia species in m. ovinus.201627884170
multispacer typing (mst) of spotted fever group rickettsiae isolated from humans and rats in chengmai county, hainan province, china.spotted fever caused by spotted fever group rickettsiae (sfgr) is found throughout china. during 2007-2008, 28 human sfgr isolates and 34 rat sfgr isolates including 15 isolates from rattus fulvescens, 5 isolates from r. edwardsi, 7 isolates from callosciurus erythraeus roberti and 7 isolates from dremomys rufigenis) were obtained from l929 cell culture. previous research indicated that the 62 strains of sfgr mentioned above shared not only the same serophenotype but also 100% of identity sequen ...201425324688
[investigation on the endemic foci of new emerged tick-borne encephalitis in charles hilary, xinjiang].to investigate the recent emerged endemic region of tick-borne encephalitis (tbe) regarding its natural reserves, in charles hilary, northern xinjiang and to isolate and characterize the viral geographic strain.201324016430
the first molecular evidence of severe fever with thrombocytopenia syndrome virus in ticks in jilin, northeastern china.severe fever with thrombocytopenia syndrome (sfts) is an emerging tick-borne zoonosis. the aim of this study was to investigate sfts virus (sftsv) infections in ticks in northeastern china. a total of 6427 ticks, including 5450 haemaphysalis longicornis, 463 dermacentor silvarum, 351 dermacentor nuttalli, and 163 ixodes persulcatus, were sampled in the liaoning, jilin, and heilongjiang provinces of northeastern china. viral megagenomic analysis of the ticks revealed 25 contigs targeting the m an ...201627460903
influence of altitude on tick-borne encephalitis infection risk in the natural foci of the altai republic, southern siberia.the altai republic is a highly endemic area as far as tick-borne encephalitis (tbe) is concerned. the aim of the research was to study the effect of altitude on the risk of tick-borne encephalitis infection in the altai republic. the paper analyzes the following data: the study of ixodid ticks collected from the vegetation in 116 sites at the 200-2383m elevation above sea level in 2012-2014, tbe virus prevalence of these vectors, tick-bite incidence rate, and tbe incidence rate of the population ...201525748512
cold tolerance and biochemical response of unfed dermacentor silvarum ticks to low temperature.the important pathogen vector dermacentor silvarum is widely distributed in china. however, the tick's adaptation to low winter temperatures remains poorly understood. we therefore investigated the cold hardiness and physiological and biochemical responses of d. silvarum ticks exposed to low temperatures. the results indicated that the lower lethal temperatures (lt50s) for larvae, nymphs, females and males were -16.9°c, -15.8°c, -20.0°c and -20.1°c, respectively. the discriminating temperatures ...201728578851
molecular prevalence of spotted fever group rickettsiae in ticks from qinghai province, northwestern china.tick-borne rickettsioses is one of the oldest known vector-borne diseases and has been viewed as emerging or re-emerging disease in china. the causative agents have been increasingly recognized and exhibited a high degree of genetic diversity and widespread distribution. this study was conducted to determine the prevalence of spotted fever group rickettsiae in ticks from qinghai province, northwestern china. in total, 860 questing adult ticks representing six species were collected. the sfg rick ...201829107656
borrelia miyamotoi infections in humans and ticks, northeastern china.we conducted an investigation of borrelia miyamotoi infections in humans and ticks in northeastern china. of 984 patients reporting recent tick bites, 14 (1.4%) were found to be infected with b. miyamotoi by pcr and genomic sequencing. the 14 patients had nonspecific febrile manifestations, including fever, headache, anorexia, asthenia, and arthralgia. rash, eschar, and regional lymphadenopathy were each observed in 1 patient. four (28.6%) patients were hospitalized because of severe disease. b. ...201829350133
Displaying items 1 - 88 of 88