| ticks (acari: ixodidae) infesting wild birds in the atlantic forest in northeastern brazil, with notes on rickettsial infection in ticks. | a total of 232 individuals representing 46 species of birds were mist-netted and screened for ticks in a region of the atlantic forest, state of bahia, brazil. thirty-eight (16.4%) of these birds representing 17 species were found infested by immature stages of amblyomma ticks, namely, amblyomma longirostre (koch, 1844) (15 larvae and seven nymphs), amblyomma nodosum (neumann, 1899) (nine nymphs), amblyomma calcaratum (neumann, 1899) (five nymphs), amblyomma cajennense (fabricius, 1787) (seven l ... | 2010 | 20953629 |
| absence of rickettsia rickettsii and occurrence of other spotted fever group rickettsiae in ticks from tennessee. | rocky mountain spotted fever (rmsf) is the most common tick-borne illness in tennessee. little is known about the occurrence of r. rickettsii, the causative agent, in ticks in tennessee. to better understand the prevalence and distribution of rickettsial agents in ticks, we tested 1,265 amblyomma, dermacentor, and ixodes adult and nymphal ticks. additionally, we tested 231 amblyomma americanum larvae. ticks were collected from 49 counties from humans, wild animals, domestic canines, and flannel ... | 2010 | 20810834 |
| bacterial pathogens in ixodid ticks from a piedmont county in north carolina: prevalence of rickettsial organisms. | in north carolina, reported human cases of tick-borne illness, specifically rocky mountain spotted fever, have escalated over the past decade. to determine the relative abundance of vectors and to estimate the risk of acquiring a tick-borne illness in peri-residential landscapes, ticks were collected in chatham county, a typical piedmont county and, samples of the ticks were tested for infection with selected bacterial pathogens using real-time quantitative polymerase chain reaction assays. tick ... | 2010 | 20455778 |
| rickettsiae in gulf coast ticks, arkansas, usa. | to determine the cause of spotted fever cases in the southern united states, we screened gulf coast ticks (amblyomma maculatum) collected in arkansas for rickettsiae. of the screened ticks, 30% had pcr amplicons consistent with rickettsia parkeri or candidatus rickettsia amblyommii. | 2010 | 20409375 |
| ticks (acari: ixodidae) infesting wild birds in the eastern amazon, northern brazil, with notes on rickettsial infection in ticks. | the aim of the study was to report tick infestations on wild birds in a region of the eastern brazilian amazon and evaluate the rickettsial infection of these ticks. wild birds captured by mist nets were examined for the presence of ticks, which were collected and identified to species by morphology or molecular methods. in addition, part of these ticks was individually tested by polymerase chain reaction targeting portions of the rickettsial genes glta and ompa. among 331 captured birds, repres ... | 2010 | 20140452 |
| wide dispersal and possible multiple origins of low-copy-number plasmids in rickettsia species associated with blood-feeding arthropods. | plasmids are mobile genetic elements of bacteria that can impart important adaptive traits, such as increased virulence or antibiotic resistance. we report the existence of plasmids in rickettsia (rickettsiales; rickettsiaceae) species, including rickettsia akari, "candidatus rickettsia amblyommii," r. bellii, r. rhipicephali, and reis, the rickettsial endosymbiont of ixodes scapularis. all of the rickettsiae were isolated from humans or north and south american ticks. r. parkeri isolates from b ... | 2010 | 20097813 |
| detection and identification of rickettsial agents in ticks from domestic mammals in eastern panama. | several outbreaks of rocky mountain spotted fever have occurred in recent years in colombian communities close to the border with panama. however, little is known about rickettsiae and rickettsial diseases in eastern panamanian provinces, the darien province and the kuna yala, located north of the endemic area in colombia. in 2007, 289 ticks were collected in several towns from dogs, horses, mules, cows, and pigs. dna was extracted from 124 dermacentor nitens, 64 rhipicephalus sanguineus, 43 amb ... | 2009 | 19645289 |
| infrequency of rickettsia rickettsii in dermacentor variabilis removed from humans, with comments on the role of other human-biting ticks associated with spotted fever group rickettsiae in the united states. | abstract from 1997 to 2009, the tick-borne disease laboratory of the u.s. army public health command (usaphc) (formerly the u.s. army center for health promotion and preventive medicine) screened 5286 dermacentor variabilis ticks removed from department of defense (dod) personnel, their dependents, and dod civilian personnel for spotted fever group rickettsiae using polymerase chain reaction and restriction fragment length polymorphism analysis. rickettsia montanensis (171/5286 = 3.2%) and ricke ... | 2010 | 21142953 |
| ticks and tick-borne pathogens and putative symbionts of black bears (ursus americanus floridanus) from georgia and florida. | ticks were collected from 38 black bears (ursus americanus floridanus) from northwestern florida (n = 18) from 2003 to 2005 and southern georgia (n = 20) in 2006. five species (amblyomma americanum, a. maculatum, dermacentor variabilis, ixodes scapularis, and i. affinis) were collected from florida bears, and 4 species (a. americanum, a. maculatum, d. variabilis, i. scapularis) were collected from bears in georgia. ixodes scapularis was the most frequently collected tick, followed by d. variabil ... | 2009 | 19413369 |
| detection of a spotted fever group rickettsia in the tick ixodes tasmani collected from koalas in port macquarie, australia. | four species of rickettsia are recognized as endemic to australia. this study reports the detection of a new spotted fever group rickettsia in the common marsupial tick ixodes tasmani neumann collected from koalas (phascolarctos cinereus) in port macquarie, nsw, australia. based on the results of polymerase chain reaction (pcr) amplification of extracted tick dna with primers targeting the citrate synthase gene (glta) and the outer membrane proteins a and b (ompa. ompb), rickettsiae were detecte ... | 2008 | 18714878 |
| canine infection by rickettsiae and ehrlichiae in southern brazil. | this study evaluated the infection caused by rickettsia and ehrlichia agents among dogs in southern brazil. a total of 389 dogs were tested by the indirect immunofluorescence assay (ifa) for rickettsia rickettsii, rickettsia parkeri, rickettsia amblyommii, rickettsia rhipicephali, rickettsia bellii, and ehrlichia canis. overall, 42.4% (165/389) of the dogs were seroreactive to at least one rickettsia species, but only 11 canine sera reacted with another rickettsia species without reacting with r ... | 2008 | 18606772 |
| tick-borne diseases in north carolina: is "rickettsia amblyommii" a possible cause of rickettsiosis reported as rocky mountain spotted fever? | cases of rocky mountain spotted fever (rmsf) in north carolina have escalated markedly since 2000. in 2005, we identified a county in the piedmont region with high case numbers of rmsf. we collected ticks and examined them for bacterial pathogens using molecular methods to determine if a novel tick vector or spotted fever group rickettsiae (sfgr) might be emerging. amblyomma americanum, the lone star tick, comprised 99.6% of 6,502 specimens collected in suburban landscapes. in contrast, dermacen ... | 2008 | 18447622 |
| ecology of rickettsia in south america. | until the year 2000, only three rickettsia species were known in south america: (i) rickettsia rickettsii, transmitted by the ticks amblyomma cajennense, and amblyomma aureolatum, reported in colombia, argentina, and brazil, where it is the etiological agent of rocky mountain spotted fever; (ii) rickettsia prowazekii, transmitted by body lice and causing epidemic typhus in highland areas, mainly in peru; (iii) rickettsia typhi, transmitted by fleas and causing endemic typhus in many countries. d ... | 2009 | 19538276 |
| rickettsia amblyommii infecting amblyomma americanum larvae. | polymerase chain reaction analysis of amblyomma americanum adults, nymphs, and larvae from aberdeen proving ground, md (apg), revealed a very high prevalence of a spotted fever group (sfg) rickettsia. restriction fragment length polymorphism (rflp) and sequence analysis identified "rickettsia amblyommii." this organism is not yet described or well studied, and its pathogenicity is unknown; however, investigations of the organism are warranted because of its high prevalence in a. americanum. this ... | 2008 | 18171102 |
| detection of rickettsia amblyommii in association with a tick bite rash. | in the summer of 2006, an amblyomma americanum tick was removed from a woman in central north carolina, who subsequently developed a rash at the site of tick attachment. when examined by polymerase chain reaction (pcr) for borrelia, anaplasma, ehrlichia, babesia, rickettsia, and bartonella dna, only the rickettsia primers generated an amplicon, which was identified as "r. amblyommii" by sequencing. to our knowledge, this is the first case in which r. amblyommii was temporally associated with a r ... | 2007 | 18052716 |
| molecular detection of rickettsia amblyommii in amblyomma americanum parasitizing humans. | a quantitative real-time polymerase chain reaction assay to detect and quantify a portion of the outer membrane protein b gene (ompb) of rickettsia amblyommii was employed to assess the threat of r. amblyommii exposure to humans parasitized by amblyomma americanum (the lone star tick). a total of 72 pools of lone star ticks removed from humans were acquired from two collections and used in this study: 44 pools of a. americanum submitted to the department of defense human tick test kit program in ... | 2010 | 19877809 |
| prevalence of ehrlichia, borrelia, and rickettsial agents in amblyomma americanum (acari: ixodidae) collected from nine states. | ambyomma americanum (l.) (acari: ixodidae) is an aggressive tick that feeds on humans during all postembryonic life stages. in many regions of the united states, it is the tick most commonly found attached to humans. public health interest has grown recently, due to the recognition of new human pathogens transmitted by a. americanum and the expanding distribution of the tick. a. americanum is a vector of several bacteria pathogenic to humans. ehrlichia chaffeensis and ehrlichia ewingii cause mod ... | 2006 | 17162962 |
| rickettsia bellii and rickettsia amblyommii in amblyomma ticks from the state of rondônia, western amazon, brazil. | this study evaluates the rickettsial presence in amblyomma ticks from eight areas of the amazon forest in rondônia, brazil. the following tick species (number in parentheses) were examined: amblyomma ovale koch (121), amblyomma cajennense (f.) (41), amblyomma naponense (packard) (36), amblyomma scalpturatum neumann (35), amblyomma oblongoguttatum koch (30), amblyomma incisum neumann (27), amblyomma rotundatum koch (16), amblyomma coelebs neumann (10), and amblyomma humerale koch (6). ticks were ... | 2004 | 15605647 |
| molecular evidence for a spotted fever group rickettsia species in the tick amblyomma longirostre in brazil. | two amblyomma longirostre adult male ticks were collected from a brazilian porcupine coendou prehensilis l. in the state of rondonia, western amazon, brazil. the two ticks were pooled for dna extraction and tested for the presence of rickettsial dna by amplifying portions of the glta, 17-kda, ompa, and ompb rickettsial genes by polymerase chain reaction (pcr). portions of the four genes were amplified from the sample and subsequently sequenced. these results indicated the presence of a rickettsi ... | 2004 | 15185961 |
| tick bites and skin rashes. | fever and a rash following a tick bite can signify a true medical emergency. ticks are important vectors of disease worldwide, including rocky mountain spotted fever, lyme disease, and congo-crimean hemorrhagic fever. this paper will review the major ticks of medical importance and the diseases they transmit, including important emerging pathogens. | 2010 | 20071986 |
| prevalence of rickettsia infection in dogs from the urban and rural areas of monte negro municipality, western amazon, brazil. | the present study evaluated the rickettsial infection among dogs living in the rural and urban areas of monte negro, state of rondônia, western brazilian amazon. canine sera were tested by the indirect immunofluorescence assay (ifa) using six rickettsial antigens: rickettsia bellii, rickettsia amblyommii, rickettsia rhipicephali, rickettsia rickettsii, rickettsia parkeri, and rickettsia felis. while the first three rickettsia species are known to occur in the study site, the latter three species ... | 2007 | 17627445 |
| characterization of rickettsial infection in amblyomma americanum (acari: ixodidae) by quantitative real-time polymerase chain reaction. | several species of the spotted fever group rickettsia (sfgr), with considerable variation in vertebrate host pathogenicity, are present in ticks in the united states. in this study, quantitative real-time pcr (qpcr) was used to characterize the growth and the distribution of rickettsia amblyommii in selected tissues (salivary glands, gut, and ovaries) of naturally infected amblyomma americanum (l.) (acari: ixodidae), during bloodmeal acquisition and throughout vertical transmission to eggs and p ... | 2008 | 18402143 |
| rickettsial infection in domestic mammals and their ectoparasites in el valle de antón, coclé, panamá. | the present research evaluated the presence of rickettsia spp. on ectoparasites of horses and dogs (using pcr techniques), and their sera (using immunofluorescence assay) in el valle de antón town in panama. a total of 20 horses and 20 dogs were sampled, finding four species of ectoparasites on dogs (the ticks rhipicephalus sanguineus, amblyomma ovale, amblyomma oblongoguttatum, and the flea ctenocephalides felis), and two tick species on horses (amblyomma cajennense and dermacentor nitens). dna ... | 2010 | 21144663 |
| a tick-borne rickettsia of the spotted-fever group, similar to rickettsia amblyommii, in french guyana. | | 2007 | 17316505 |
| spotted fever group rickettsia infecting ticks (acari: ixodidae) in the state of santa catarina, brazil. | during 2006-2008, a total of 260 adult ticks were collected from domestic and wild animals in different regions of the state of santa catarina (sc), brazil, including areas where human cases of brazilian spotted fever have been reported. collected ticks belonging to nine species (amblyomma aureolatum, amblyomma cajennense, amblyomma dubitatum, amblyomma longirostre, amblyomma ovale, amblyomma tigrinum, dermacentor nitens, rhipicephalus microplus and rhipicephalus sanguineus) were tested by polym ... | 2011 | 22241112 |
| a prevalent alpha-proteobacterium paracoccus sp. in a population of the cayenne ticks (amblyomma cajennense) from rio de janeiro, brazil. | as rocky mountain spotted fever is the most common tick-borne disease in south america, the presence of rickettsia sp. in amblyomma ticks is a possible indication of its endemicity in certain geographic regions. in the present work, bacterial dna sequences related to rickettsia amblyommii genes in a. dubitatum ticks, collected in the brazilian state of mato grosso, were discovered. simultaneously, paracoccus sp. was detected in aproximately 77% of a. cajennense specimens collected in rio de jane ... | 2012 | 23271948 |
| development of shuttle vectors for transformation of diverse rickettsia species. | plasmids have been identified in most species of rickettsia examined, with some species maintaining multiple different plasmids. three distinct plasmids were demonstrated in rickettsia amblyommii aar/sc by southern analysis using plasmid specific probes. copy numbers of pram18, pram23 and pram32 per chromosome in aar/sc were estimated by real-time pcr to be 2.0, 1.9 and 1.3 respectively. cloning and sequencing of r. amblyommii aar/sc plasmids provided an opportunity to develop shuttle vectors fo ... | 2011 | 22216299 |
| infection by rickettsia bellii and candidatus "rickettsia amblyommii" in amblyomma neumanni ticks from argentina. | the tick species, amblyomma neumanni (acari: ixodidae) is the most frequent tick parasitizing humans in northwestern argentina. the present study evaluated the rickettsial infection among 55 a. neumanni adult free-living ticks collected in dean funes, córdoba province. ticks were individually processed by the hemolymph test with gimenez staining, isolation of rickettsia in vero cell culture by the shell vial technique, and polymerase chain reaction (pcr) targeting the citrate synthase rickettsia ... | 2007 | 17264991 |
| diversity of rickettsiales in the microbiome of the lone star tick, amblyomma americanum. | ticks are important vectors for many emerging pathogens. however, they are also infected with many symbionts and commensals, often competing for the same niches. in this paper, we characterize the microbiome of amblyomma americanum (acari: ixodidae), the lone star tick, in order to better understand the evolutionary relationships between pathogens and nonpathogens. multitag pyrosequencing of prokaryotic 16s rrna genes (16s rrna) was performed on 20 lone star ticks (including males, females, and ... | 2014 | 24162580 |
| tick-borne bacteria in free-living jaguars (panthera onca) in pantanal, brazil. | abstract tick-borne bacteria were investigated in 10 free-living jaguars and their ticks in the pantanal biome, brazil. jaguar sera were tested by indirect fluorescent antibody assays using rickettsia rickettsii, rickettsia parkeri, rickettsia amblyommii, rickettsia rhipicephali, rickettsia felis, rickettsia bellii, ehrlichia canis, and coxiella burnetii as crude antigens. all 10 jaguar sera reacted (titer ≥64) to at least one rickettsia species; 4 and 3 sera reacted with e. canis and c. burneti ... | 2011 | 21612532 |
| ticks and spotted fever group rickettsiae of southeastern virginia. | the incidence of tick-borne rickettsial disease in the southeastern united states has been rising steadily through the past decade, and the range expansions of tick species and tick-borne infectious agents, new and old, has resulted in an unprecedented mix of vectors and pathogens. the results of an ongoing 4-year surveillance project describe the relative abundance of questing tick populations in southeastern virginia. since 2009, more than 66,000 questing ticks of 7 species have been collected ... | 2013 | 24201057 |
| detection of human bacterial pathogens in ticks collected from louisiana black bears (ursus americanus luteolus). | there are 4 major human-biting tick species in the northeastern united states, which include: amblyomma americanum, amblyomma maculatum, dermacentor variabilis, and ixodes scapularis. the black bear is a large mammal that has been shown to be parasitized by all the aforementioned ticks. we investigated the bacterial infections in ticks collected from louisiana black bears (ursus americanus subspecies luteolus). eighty-six ticks were collected from 17 black bears in louisiana from june 2010 to ma ... | 2013 | 23415850 |
| synanthropic mammals as potential hosts of tick-borne pathogens in panama. | synanthropic wild mammals can be important hosts for many vector-borne zoonotic pathogens. the aim of this study was determine the exposure of synanthropic mammals to two types of tick-borne pathogens in panama, spotted fever group rickettsia (sfgr) and borrelia relapsing fever (rf) spirochetes. one hundred and thirty-one wild mammals were evaluated, including two gray foxes, two crab-eating foxes (from zoos), four coyotes, 62 opossum and 63 spiny rats captured close to rural towns. to evaluate ... | 2017 | 28060928 |
| ticks and rickettsiae from wildlife in belize, central america. | the agents of spotted fevers in latin america are rickettsia rickettsii, r. parkeri, rickettsia sp. strain atlantic rainforest, and r. massiliae. in continental central america, r. rickettsii remains the only known pathogenic tick-borne rickettsia. in the present study, ticks were collected from wild mammals in natural areas of belize. besides providing new data of ticks from belize, we investigated rickettsial infection in some of these ticks. our results provide ticks harboring rickettsial age ... | 2016 | 26831147 |
| questing amblyomma mixtum and haemaphysalis juxtakochi (acari: ixodidae) infected with candidatus "rickettsia amblyommii" from the natural environment in panama canal basin, panama. | this work emphasizes the detection of candidatus "rickettsia amblyommii" in questing haemaphysalis juxtakochi and amblyomma mixtum. from february 2009 to december 2012, questing ticks were collected from the vegetation and leaf-litter of four protected forests and two grassy areas around the panama canal basin. dna was extracted from amblyomma mixtum, amblyomma naponense, amblyomma oblongoguttatum, amblyomma pecarium, amblyomma tapirellum, haemaphysalis juxtakochi, and unidentified immature ambl ... | 2015 | 26865823 |
| rickettsia amblyommii infecting amblyomma sculptum in endemic spotted fever area from southeastern brazil. | the rickettsia bacteria include the aetiological agents for the human spotted fever (sf) disease. in the present study, a sf group rickettsia amblyommii related bacterium was detected in a field collected amblyomma sculptum (amblyomma cajennense species complex) tick from a brazilian sf endemic site in southeastern brazil, in the municipality of juiz de fora, state of minas gerais. genetic analysis based on genes ompa,ompb and htra showed that the detected strain, named r. amblyommii str. jf, is ... | 2015 | 26676317 |
| vector potential and population dynamics for amblyomma inornatum. | we studied the natural life cycle of amblyomma inornatum and its vector potential in south texas. this tick is distributed throughout south texas and most of central america. a. inornatum represented 1.91% of the ticks collected by carbon dioxide traps during a study of free-living ticks in the tamaulipan biotic province in south texas. the life cycle of a. inornatum in south texas showed a clear seasonal pattern consistent with one generation per year. nymphs emerged in the spring with a peak i ... | 2015 | 25881916 |
| immunoproteomic profiling of rickettsia parkeri and rickettsia amblyommii. | rickettsia parkeri is an amblyomma-associated, spotted fever group rickettsia species that causes an eschar-associated, febrile illness in multiple countries throughout the western hemisphere. many other rickettsial species of known or uncertain pathogenicity have been detected in amblyomma spp. ticks in the americas, including rickettsia amblyommii, "candidatus rickettsia andeanae" and rickettsia rickettsii. in this study, we utilized an immunoproteomic approach to compare antigenic profiles of ... | 2015 | 26234571 |
| detection of rickettsia amblyommii in ticks collected from missouri, usa. | | 2014 | 26038740 |
| expanding range of amblyomma americanum and simultaneous changes in the epidemiology of spotted fever group rickettsiosis in the united states. | spotted fever group (sfg) rickettsia species are etiologic agents of a wide range of human infections from asymptomatic or mild infections to severe, life-threatening disease. in the united states, recent passive surveillance for sfg rickettsiosis shows an increased incidence and decreased severity of reported cases. the reasons for this are not well understood; however, we hypothesize that less pathogenic rickettsiae are causing more human infections, while the incidence of disease caused by mo ... | 2015 | 26503270 |
| prevalence of rickettsiales in ticks removed from the skin of outdoor workers in north carolina. | tick-transmitted rickettsial diseases, such as ehrlichiosis and spotted fever rickettsiosis, are significant sources of morbidity and mortality in the southern united states. because of their exposure in tick-infested woodlands, outdoor workers experience an increased risk of infection with tick-borne pathogens. as part of a double blind randomized-controlled field trial of the effectiveness of permethrin-treated clothing in preventing tick bites, we identified tick species removed from the skin ... | 2014 | 25533148 |
| seroepidemiologic study of human infections with spotted fever group rickettsiae in north carolina. | increasing entomologic and epidemiologic evidence suggests that spotted fever group rickettsiae (sfgr) other than rickettsia rickettsii are responsible for spotted fever rickettsioses in the united states. a retrospective seroepidemiologic study was conducted on stored acute- and convalescent-phase sera that had been submitted for rocky mountain spotted fever testing to the north carolina state laboratory of public health. we evaluated the serologic reactivity of the paired sera to r. rickettsii ... | 2014 | 25187639 |
| cultivation of rickettsia amblyommii in tick cells, prevalence in florida lone star ticks (amblyomma americanum). | rickettsia amblyommii is a bacterium in the spotted fever group of organisms associated with the lone star tick (lst), amblyomma americanum. the lst is the most commonly reported tick to parasitize humans in the southeastern us. within this geographic region, there have been suspected cases of rocky mountain spotted fever (rmsf) where the causative agent, r. rickettsii, was not identified in the local tick population. in these areas, patients with clinical signs of rmsf had low or no detectable ... | 2014 | 24927809 |
| importation of exotic ticks and tick-borne spotted fever group rickettsiae into the united states by migrating songbirds. | birds are capable of carrying ticks and, consequently, tick-transmitted microorganisms over long distances and across geographical barriers such as oceans and deserts. ticks are hosts for several species of spotted fever group rickettsiae (sfgr), which can be transmitted to vertebrates during blood meals. in this study, the prevalence of this group of rickettsiae was examined in ticks infesting migratory songbirds by using polymerase chain reaction (pcr). during the 2009 and 2010 spring migratio ... | 2013 | 24252263 |
| first report of the isolation and molecular characterization of rickettsia amblyommii and rickettsia felis in central america. | abstract during 2010, 15 adult ticks, identified as amblyomma cajennense, were collected from horses in cahuita and turrialba districts, whereas 7 fleas, identified as ctenocephalides felis, were collected from a dog in san jose city, costa rica. in the laboratory, three a. cajennense specimens, two from cahuita and one from turrialba, were individually processed for rickettsial isolation in cell culture, as was a pool of seven fleas. rickettsiae were successfully isolated and established in ver ... | 2011 | 21612539 |
| detection of rickettsia bellii and rickettsia amblyommii in amblyomma longirostre (acari: ixodidae) from bahia state, northeast brazil. | studies investigating rickettsial infections in ticks parasitizing wild animals in the northeast region of brazil have been confined to the detection of rickettsia amblyommii in immature stages of amblyomma longirostre collected from birds in the state of bahia, and in immatures and females of amblyomma auricularium collected from the striped hog-nosed skunk (conepatus semistriatus) and armadillos (euphractus sexcinctus) in the state of pernambuco. the current study extends the distribution of r ... | 2015 | 26413074 |
| rickettsia bellii, rickettsia amblyommii, and laguna negra hantavirus in an indian reserve in the brazilian amazon. | the purpose of this study was to identify the presence of rickettsia and hantavirus in wild rodents and arthropods in response to an outbreak of acute unidentified febrile illness among indians in the halataikwa indian reserve, northwest of the mato grosso state, in the brazilian amazon. where previously surveillance data showed serologic evidence of rickettsia and hantavirus human infection. | 2014 | 24742108 |
| molecular phylogeny and rearrangement of rrna genes in rickettsia species. | it has previously been observed that rickettsia prowazekii has an unusual arrangement of the rrna genes. in this species, the three rrna genes, 16s (rrs), 23s (rrl), and 5s (rrf), are not linked in the typical arrangements for bacteria. rather, the 16s rrna gene has been separated from the 23s and 5s rrna gene cluster, and the 23s rrna gene is preceded by a gene which codes for methionyl-trnaf(met) formyltransferase (fmt). in this study, we screened the genus rickettsia for the fmt-rrl motif in ... | 1999 | 10406115 |
| a survey of tick-borne pathogens in dogs and their ticks in the pantanal biome, brazil. | tick and blood samples collected from domestic dogs in the brazilian pantanal were tested by molecular methods for the presence of tick-borne protozoa and bacteria. among 320 sampled dogs, 3.13% were infected by babesia vogeli (piroplasmida: babesiidae), 8.75% by hepatozoon canis (eucoccidiorida: hepatozoidae), 7.19% by anaplasma platys (rickettsiales: anaplasmataceae), and 0.94% by an unclassified anaplasma sp. in three tick species collected from dogs, the following tick-borne agents were dete ... | 2016 | 26467462 |
| prevalence of tick-borne pathogens in host-seeking amblyomma americanum (acari: ixodidae) and odocoileus virginianus (artiodactyla: cervidae) in florida. | amblyomma americanum (l.), the lone star tick, is an aggressive tick that is expanding its geographic range within the united states. this tick is the vector for the human and veterinary pathogens ehrlichia chaffeensis and ehrlichia ewingii and is associated with other microbes of unspecified pathogenicity including rickettsia amblyommii, panola mountain ehrlichia, and borrelia lonestari in florida, there has been sparse contemporary data on the prevalence of these organisms in host-seeking lone ... | 2016 | 27117680 |
| detection of bacterial agents in amblyomma americanum (acari: ixodidae) from georgia, usa, and the use of a multiplex assay to differentiate ehrlichia chaffeensis and ehrlichia ewingii. | amblyomma americanum, the lone star tick, is the most common and most aggressive human biting tick in the southeastern united states. it is known to transmit the agents of human ehrlichioses, ehrlichia chaffeensis and ehrlichia ewingii. in addition, it carries agents of unspecified pathogenicity to humans, including rickettsia amblyommii, borrelia lonestari, and the newly emerging panola mountain ehrlichia (pme). surveillance of these ticks for recognized or emerging pathogens is necessary for a ... | 2014 | 25118421 |
| detection of borrelia, ehrlichia, and rickettsia spp. in ticks in northeast missouri. | we evaluated amblyomma americanum (lone star tick) and dermacentor variabilis (american dog tick) in northeast missouri for the presence of borrelia, ehrlichia, and rickettsia bacteria. we collected actively questing ticks from four sites within adair county, missouri. a total of 15,162 ticks were collected, of which 13,980 were grouped in 308 pools (lone star ticks, 288 pools; american dog ticks, 20 pools) and tested for presence/absence of bacteria using polymerase chain reaction. infection ra ... | 2016 | 27133163 |
| Geographical distribution and prevalence of selected Borrelia, Ehrlichia, and Rickettsia infections in Amblyomma americanum (Acari: Ixodidae) in New Jersey. | We used published accounts to describe the known statewide distribution of the lone star tick, Amblyomma americanum, in New Jersey and field surveys to characterize the geographical range of A. americanum and selected A. americanum-transmitted pathogens in Monmouth County, the hypothesized northern limit of the species distribution. Ticks were collected using standardized methods from 50 widely dispersed public access areas within 18 municipalities to produce estimates of relative abundance amon ... | 2011 | 22017087 |
| gene expression of tissue-specific molecules in ex vivo dermacentor variabilis (acari: ixodidae) during rickettsial exposure. | ticks serve as both vectors and the reservoir hosts capable of transmitting spotted fever group rickettsia by horizontal and vertical transmission. persistent maintenance of rickettsia species in tick populations is dependent on the specificity of the tick and rickettsia relationship that limits vertical transmission of particular rickettsia species, suggesting host-derived mechanisms of control. tick-derived molecules are differentially expressed in a tissue-specific manner in response to ricke ... | 0 | 24180114 |
| molecular characterization and tissue-specific gene expression of dermacentor variabilis α-catenin in response to rickettsial infection. | alpha catenin is a cytoskeleton protein that acts as a regulator of actin rearrangement by forming an e-cadherin adhesion complex. in dermacentor variabilis, a putative α-catenin (dvα-catenin) was previously identified as differentially regulated in ovaries of ticks chronically infected with rickettsia montanensis. to begin characterizing the role(s) of dvα-catenin during rickettsial infection, the full-length dvα-catenin cdna was cloned and analysed. comparative sequence analysis demonstrates a ... | 2012 | 22221256 |
| incident tick-borne infections in a cohort of north carolina outdoor workers. | tick-borne diseases cause substantial morbidity throughout the united states, and north carolina has a high incidence of spotted fever rickettsioses and ehrlichiosis, with sporadic cases of lyme disease. the occupational risk of tick-borne infections among outdoor workers is high, particularly those working on publicly managed lands. this study identified incident tick-borne infections and examined seroconversion risk factors among a cohort of north carolina outdoor workers. workers from the nor ... | 2016 | 27008102 |
| epidemiology of spotted fever group rickettsioses and acute undifferentiated febrile illness in villeta, colombia. | etiology of acute undifferentiated febrile syndrome (aufs) is often unknown, leading to inaccurate diagnosis and treatment. villeta town has been identified as an endemic area for spotted fever group (sfg) rickettsioses but little is known about possible amplifier hosts and other rickettsia species different from rickettsia rickettsii. besides, few studies have approached other aufs etiologies in the region. we investigated the role of dengue, leptospirosis, rickettsioses, human anaplasmosis, an ... | 2017 | 28722568 |
| a study of ticks and tick-borne livestock pathogens in pakistan. | as obligate blood-feeding arthropods, ticks transmit pathogens to humans and domestic animals more often than other arthropod vectors. livestock farming plays a vital role in the rural economy of pakistan, and tick infestation causes serious problems with it. however, research on tick species diversity and tick-borne pathogens has rarely been conducted in pakistan. in this study, a systematic investigation of the tick species infesting livestock in different ecological regions of pakistan was co ... | 2017 | 28650978 |
| dynamics of exposure to rickettsia parkeri in cattle in the paraná river delta, argentina. | several cases of human rickettsiosis caused by rickettsia parkeri were recently documented in the paraná river delta of argentina, where the tick vector is amblyomma triste koch. as cattle suffer recurrent a. triste infestations, they are at risk of becoming infected with r. parkeri herein we investigated the dynamics of r. parkeri and its a. triste vector in a herd of beef cattle. cattle were followed for 18 mo and samples were analyzed for the presence of antibodies against four rickettsia spe ... | 2016 | 26794232 |
| rickettsiae and ehrlichiae within a city park: is the urban dweller at risk? | tick-borne diseases, such as spotted fever rickettsioses and ehrlichioses, are potentially severe and life-threatening infections. the incidences of these infections increase during warm weather months as ticks become active. clinicians often consider outdoor activities in rural areas to be a risk factor for exposure to ticks and the pathogens they carry, but are those who live, work, and play within an urban environment excluded from this risk? in this study, we collected ticks from two urban p ... | 2014 | 24528097 |
| seroprevalence of tick-borne pathogens and tick infestation in dogs from tapirapé and karajá indigenous communities, brazil. | with the aim of studying some tick-borne diseases, a total of 327 dogs (114 from tapirapé and 213 from karajá indigenous ethnicity, mato grosso, mt, brazil) were sampled. serum samples were submitted to the indirect fluorescence antibody test (ifat) to detect antibodies against babesia vogeli, ehrlichia canis, and rickettsia spp. possible associations of risk factors and the occurrence of seroreativity to tick-borne agents and tick infestations were analyzed through chi-squared tests. among 327 ... | 2015 | 26186512 |
| ecology of a tick-borne spotted fever in southern brazil. | rio grande do sul is the southernmost state of brazil, bordering uruguay. clinical cases of spotted fever group (sfg) rickettsiosis were recently reported in rio grande do sul. none of these cases was lethal, and all were confirmed by seroconversion to r. rickettsii antigens. because serological cross-reactions are well known to occur between different sfg agents, the sfg agent responsible for the clinical cases remains unknown in rio grande do sul, where no rickettsial agent is known to infect ... | 2016 | 27392739 |
| rickettsial agents in avian ixodid ticks in northeast brazil. | birds are important in the maintenance and spread of ticks and tick-borne diseases. in this context we screened birds in the atlantic forest north of the são francisco river and caatinga in northeast brazil. in the atlantic forest amblyomma longirostre, amblyomma nodosum, amblyomma varium and amblyomma auricularium were identified. a. longirostre was infected by "candidatus rickettsia amblyommii" and a. nodosum by a rickettsia parkeri-like agent. in caatinga, amblyomma parvum and a. auricularium ... | 2015 | 25800099 |
| rickettsia infection in amblyomma tonelliae, a tick species from the amblyomma cajennense complex. | the present study was performed to evaluate the rickettsia infection in amblyomma tonelliae ticks from argentina. all ticks were subjected to dna extraction and tested by a battery of pcrs to amplify fragments of four rickettsial genes, 23s-5s, glta, ompa and htra. two ticks were positive. the rickettsia detected in one tick represents a new lineage which is named rickettsia sp. strain el tunal. this new strain belongs to the canadensis group because it is closely related to rickettsia monteiroi ... | 2015 | 25544308 |
| rickettsia parkeri transmission to amblyomma americanum by cofeeding with amblyomma maculatum (acari: ixodidae) and potential for spillover. | amblyomma americanum (l.) is a human-biting ixodid tick distributed throughout much of the southeastern united states. rickettsia parkeri is a member of the spotted fever group rickettsiae and causes a febrile illness in humans commonly referred to as "tidewater spotted fever" or "r. parkeri rickettsiosis." although the gulf coast tick, amblyomma maculatum koch, is the primary vector of r. parkeri, a small proportion of a. americanum have also been shown to harbor r. parkeri. the purpose of this ... | 2015 | 26336226 |
| rickettsial infection in animals, humans and ticks in paulicéia, brazil. | a previous study in paulicéia municipality, south-eastern brazil, reported 9.7% of the amblyomma triste ticks to be infected by rickettsia parkeri, a bacterial pathogen that causes spotted fever in humans. these a. triste ticks were shown to be associated with marsh areas, where the marsh deer blastocerus dichotomus is a primary host for this tick species. during 2008-2009, blood serum samples were collected from 140 horses, 41 dogs, 5 opossums (didelphis albiventris) and 26 humans in farms from ... | 2015 | 25643912 |
| molecular detection of rickettsia rhipicephali and other spotted fever group rickettsia species in amblyomma ticks infesting wild birds in the state of minas gerais, brazil. | the current study evaluated parasitism of wild birds by ticks in a fragment of atlantic forest in the state of minas gerais, brazil, and examined the ticks for rickettsial agents. birds were captured during 2014 and 2015 and ticks were identified by sequencing fragments of the 16s and 12s ribosomal dna. among 260 birds representing 19 families and 52 species, a total of 69 (26.5%) were found to be infested by larvae (ll) and/or nymphs (nn) of amblyomma longirostre (koch, 1844) (45 ll, 4 nn), amb ... | 2017 | 27745888 |
| an insight into the microbiome of the amblyomma maculatum (acari: ixodidae). | the aim of this study was to survey the bacterial diversity of amblyomma maculatum koch, 1844, and characterize its infection with rickettsia parkeri. pyrosequencing of the bacterial 16s rrna was used to determine the total bacterial population in a. maculatum. pyrosequencing analysis identified rickettsia in a. maculatum midguts, salivary glands, and saliva, which indicates successful trafficking in the arthropod vector. the identity of rickettsia spp. was determined based on sequencing the ric ... | 0 | 24605461 |
| pathogenic potential of a costa rican strain of 'candidatus rickettsia amblyommii' in guinea pigs (cavia porcellus) and protective immunity against rickettsia rickettsii. | 'candidatus rickettsia amblyommii' is a spotted fever group rickettsia that is not considered pathogenic, although there is serologic evidence of possible infection in animals and humans. the aim of this study was to evaluate the pathogenic potential of a costa rican strain of 'candidatus r. amblyommii' in guinea pigs and determine its capacity to generate protective immunity against a subsequent infection with a local strain of rickettsia rickettsii isolated from a human case. six guinea pigs w ... | 2015 | 26210090 |
| "rickettsia amblyommii" induces cross protection against lethal rocky mountain spotted fever in a guinea pig model. | rocky mountain spotted fever (rmsf) is a severe illness caused by rickettsia rickettsii for which there is no available vaccine. we hypothesize that exposure to the highly prevalent, relatively nonpathogenic "rickettsia amblyommii" protects against r. rickettsii challenge. to test this hypothesis, guinea pigs were inoculated with "r. amblyommii." after inoculation, the animals showed no signs of illness. when later challenged with lethal doses of r. rickettsii, those previously exposed to "r. am ... | 2014 | 25072985 |
| "rickettsia amblyommii" and r. montanensis infection in dogs following natural exposure to ticks. | to determine the risk of canine infection with spotted fever group (sfg) rickettsia spp. following natural tick exposure, 10 dogs determined to be free of evidence of exposure to or infection with tick-borne disease agents were exposed to ticks via weekly walks in a wooded area in north-central oklahoma. after each walk, dogs were examined and the number and species of ticks present were recorded. the dogs were then returned to outdoor kennels to allow the infestations and subsequent transmissio ... | 2014 | 24359419 |
| a serological and molecular survey of babesia vogeli, ehrlichia canis and rickettsia spp. among dogs in the state of maranhão, northeastern brazil. | this study evaluated exposure and infection by tick-borne agents (babesia vogeli, ehrlichia canis and rickettsia spp.) in 172 dogs in rural areas and 150 dogs in urban areas of the municipality of chapadinha, state of maranhão, northeastern brazil, using molecular and serological methods. overall, 16.1% of the sampled dogs (52/322) were seroreactive to b. vogeli, with endpoint titers ranging from 40 to 640. for e. canis, 14.6% of the dogs (47/322) were seroreactive, with endpoint titers from 80 ... | 2015 | 25909250 |
| human infections by multiple spotted fever group rickettsiae in tennessee. | rocky mountain spotted fever is the most common tick-borne disease in tennessee. however, rickettsia rickettsii has rarely been isolated from endemic ticks, suggesting rickettsioses may be caused by other species. a total of 56 human serum samples that were serologically positive for exposure to rickettsia were obtained from commercial laboratories in 2010 and 2011. in addition, 20 paired sera from patients with encephalitis and positive rickettsia serology were obtained from the tennessee unexp ... | 2016 | 27022147 |
| molecular detection of rickettsia species within ticks (acari: ixodidae) collected from arkansas united states. | rocky mountain spotted fever (rmsf), caused by the etiological agent rickettsia rickettsii, is the most severe and frequently reported rickettsial illness in the united states, and is commonly diagnosed throughout the southeast. with the discoveries of rickettsia parkeri and other spotted fever group rickettsiae (sfgr) in ticks, it remains inconclusive if the cases reported as rmsf are truly caused by r. rickettsii or other sfgr. arkansas reports one of the highest incidence rates of rmsf in the ... | 2015 | 26334827 |
| ticks and rickettsial infection in the wildlife of two regions of the brazilian amazon. | during 2009-2012, wild animals and their ticks were sampled in two areas within the amazon biome of brazil, in the states of mato grosso and pará. animal tissues, blood, and ticks were molecularly tested for rickettsia and coxiella dna. a total of 182 wild animals were sampled, comprising 28 mammalian, five avian, and three reptilian species. animal tissues or blood were all negative for rickettsia or coxiella dna. a total of 454 ticks (22 larvae, 226 nymphs, 127 males, 79 females) were collecte ... | 2015 | 25273064 |
| the prevalence of rickettsial and ehrlichial organisms in amblyomma americanum ticks collected from ohio and surrounding areas between 2000 and 2010. | the lone star tick, amblyomma americanum, feeds upon a variety of hosts and is a known vector of several human pathogens. in ohio, populations of a. americanum have been expanding their range and increasing in abundance and distribution, thereby elevating the public health concerns regarding bites from this species. we used a set of pcr assays to detect the presence of ehrlichial and rickettsial species in a. americanum ticks submitted to the ohio department of health zoonotic disease program ov ... | 2014 | 25108789 |
| gfpuv-expressing recombinant rickettsia typhi: a useful tool for the study of pathogenesis and cd8(+) t cell immunology in rickettsia typhi infection. | rickettsia (r) typhi is the causative agent of endemic typhus, a disease that occurs wordwide with increasing incidence and can be fatal. because of its obligate intracellular life style, genetic manipulation of this pathogen is difficult. nonetheless, in recent years genetic manipulation tools have been successfully applied to rickettsiae. we describe here for the first time the transformation of r. typhi with the pram18drga plasmid that originally derives from r. amblyommatis and encodes for t ... | 2017 | 28289147 |
| amblyomma sculptum: genetic diversity and rickettsias in the brazilian cerrado biome. | amblyomma sculptum (ixodida: ixodidae) berlese, 1888 is the most important tick vector in brazil, transmitting the bioagent of the most severe form of spotted fever (sf) in part of the cerrado (in the states of minas gerais and são paulo). in another part of the cerrado (central-west region of brazil), a milder form of sf has been recorded. however, neither the rickettsia nor the vector involved have been characterized. the aim of the current study was to analyse genetic variation and the presen ... | 2017 | 28752684 |
| investigating the adult ixodid tick populations and their associated anaplasma, ehrlichia, and rickettsia bacteria at a rocky mountain spotted fever hotspot in western tennessee. | ehrlichiosis and rickettsiosis are two common bacterial tick-borne diseases in the southeastern united states. ehrlichiosis is caused by ehrlichiae transmitted by amblyomma americanum and rickettsiosis is caused by rickettsiae transmitted by amblyomma maculatum and dermacentor variabilis. these ticks are common and have overlapping distributions in the region. the objective of this study was to identify anaplasma, ehrlichia, and rickettsia species associated with questing ticks in a rocky mounta ... | 2017 | 28598270 |
| rickettsia amblyommatis infecting ticks and exposure of domestic dogs to rickettsia spp. in an amazon-cerrado transition region of northeastern brazil. | this study was performed in maranhão state, a transition area two brazilian biomes, amazon and cerrado. during 2011-2013, 1,560 domestic dogs were sampled for collection of serum blood samples and ticks in eight counties (3 within the amazon and 5 within the cerrado). a total of 959 ticks were collected on 150 dogs (9.6%). rhipicephalus sanguineus sensu lato (s.l.) was the most abundant tick (68% of all collected specimens), followed by amblyomma cajennense sensu lato (s.l.) (12.9%), amblyomma p ... | 2017 | 28594882 |
| comparative vertical transmission of rickettsia by dermacentor variabilis and amblyomma maculatum. | the geographical overlap of multiple rickettsia and tick species coincides with the molecular detection of a variety of rickettsial agents in what may be novel tick hosts. however, little is known concerning transmissibility of rickettsial species by various tick hosts. to examine the vertical transmission potential between select tick and rickettsial species, two sympatric species of ticks, dermacentor variabilis and amblyomma maculatum, were exposed to five different rickettsial species, inclu ... | 2017 | 28433729 |
| first report of a rickettsia asembonensis related infecting fleas in brazil. | the present study was performed in a non-endemic area for spotted fever (sf) in imperatriz microregion, state of maranhão, brazil. blood samples and ectoparasites were collected from 300 dogs of the imperatriz microregion. canine serum samples were tested individually by indirect immunofluorescence assay (ifa), using five rickettsia isolates from brazil. antibodies reactive to at least one of the five species of rickettsia were detected in 1.6% of the dogs (5/300). these sera were considered rea ... | 2017 | 28427962 |
| the microbiome of neotropical ticks parasitizing on passerine migratory birds. | seasonal migration of passerine birds between temperate north america and tropical central and south america is an ecological phenomenon. migration of birds has been associated with the introduction of ectoparasites like ticks or tick-borne pathogens across the avian migration routes. in this study, the microbial diversity was determined in the ticks and bird dna samples using 454 pyrosequencing of bacterial 16s rrna gene. tick dna samples showed the dominance of genera lactococcus, francisella, ... | 2017 | 27802919 |
| high prevalence of "candidatus rickettsia amblyommii" in amblyomma ticks from a spotted fever endemic region in north argentina. | ticks from an endemic spotted fever region in argentina were analysed by pcr for spotted fever group rickettsiae. dna of "candidatus rickettsia amblyommii" was found in 21.3% of amblyomma hadanii and in 44.0% of a. neumanni. amblyomma sculptum (formerly a. cajennense) and haemaphysalis juxtakochi were negative for rickettsial dna. dna of rickettsia rickettsii, the etiological agent of the clinical cases reported within the studied region was not detected in the analysed sample. | 2016 | 27260814 |
| distribution of spotted fever group rickettsiae in hard ticks (ixodida: ixodidae) from panamanian urban and rural environments (2007-2013). | tick-borne rickettsiosis is an important emerging disease in panama; to date, there have been 12 confirmed cases, including eight fatalities. to evaluate the distribution of rickettsiae in panamanian ticks, we collected questing and on-host ticks in urban and rural towns in elevations varying between 0 and 2300 m. a total of 63 sites (13 urban and 50 rural towns) were used to develop models of spatial distributions. we found the following tick species: rhipicephalus sanguineus s.l. (present in 5 ... | 2016 | 27068930 |
| rickettsia amblyommii infecting amblyomma auricularium ticks in pernambuco, northeastern brazil: isolation, transovarial transmission, and transstadial perpetuation. | this study investigated rickettsial infection in amblyomma auricularium ticks from the state of pernambuco, northeastern brazil. an engorged female of a. auricularium collected from a skunk (conepatus semistriatus) was sent alive to the laboratory, where the female was found through molecular analysis to be infected by rickettsia amblyommii. this engorged female oviposited, and its offspring was reared through three consecutive generations, always using tick-naïve rabbits to feed the ticks. pcr ... | 2013 | 23705586 |
| molecular evidence of different rickettsia species in villeta, colombia. | the aim of this work was to detect and identify rickettsia species in ticks collected in rural areas of villeta, colombia. tick specimens were collected from domestic animals and walls of houses in five rural villages of villeta town and from humans in naranjal village (same town). moreover, a flea collected from the same area was also processed. dna was extracted and tested by conventional, semi-nested, and nested pcr reactions targeting rickettsial genes. in the ticks collected from humans fro ... | 2016 | 26789730 |
| rickettsial infection in ticks (acari: ixodidae) collected on birds in southern brazil. | the aim of the study was to evaluate rickettsial infection in ticks from wild birds of the semidecidual and atlantic rainforest remnants of three municipalities of the state of paraná, southern brazil. overall, 53 larvae and nymphs collected from birds were checked for the presence of rickettsia dna by molecular tests. five tick species were tested: amblyomma aureolatum (pallas), amblyomma calcaratum neumann, amblyomma longirostre (koch), amblyomma ovale koch, and amblyomma parkeri fonseca and a ... | 2012 | 22679880 |
| rickettsia amblyommatis sp. nov., a spotted fever group rickettsia associated with multiple species of amblyomma ticks in north, central and south america. | in 1973, investigators isolated a rickettsial organism, designated strain wb-8-2t, from an adult amblyomma americanum tick collected at land between the lakes national recreation area, tn, usa. this organism is now recognized as highly prevalent in a. americanum, as well as several other amblyomma species found throughout the western hemisphere. it has been suggested that cross-reactivity to wb-8-2t and similar strains contributes to the increasing number of spotted fever cases reported in the u ... | 2016 | 27638476 |
| emerging tick-borne rickettsia and ehrlichia at joint base langley-eustis, fort eustis, virginia. | four species of ticks known to parasitize humans (amblyomma americanum (lone star tick), dermacentor variabilis (american dog tick), amblyomma maculatum (gulf coast tick), and ixodes scapularis (black-legged tick)) were collected at joint base langley-eustis, fort eustis, virginia during 2009. these ticks were tested individually (adults and nymphs) and in pools of 15 (larvae) for pathogens of public health importance within the genera: rickettsia, borrelia, and ehrlichia, by quantitative real-t ... | 2016 | 27613206 |
| [detection of rickettsia in ectoparasites of wild and domestic mammals from the cerro chucanti private reserve and from neighboring towns, panamá, 2007-2010]. | ectoparasites are the main vectors of rickettsiosis. in panama, however, limited data are available concerning the arthropod species that serve as vectors or reservoirs. | 2012 | 23242292 |
| spotted fever group rickettsiae in amblyomma ticks likely to infest humans in rural areas from northwestern argentina. | this work was performed to detect rickettsia species of the spotted fever group in amblyomma ticks likely to infest humans in rural areas from northwestern argentina. free-living ticks were collected and determined as amblyomma tigrinum, amblyomma neumanni and amblyomma tonelliae. rickettsia infection was determined by polymerase chain reactions which amplify fragments of the rickettsial genes glta and ompa. a high frequency (35/44, 79.5%) of candidatus "rickettsia andeanae" was observed in a. t ... | 2015 | 26707663 |
| first report of "candidatus rickettsia amblyommii" in west coast of mexico. | we report the first case of "candidatus rickettsia amblyommii" detected in amblyomma mixtum ticks on humans on the west coast of mexico. this is the most western record of "ca. r. amblyommii" in the western hemisphere, representing the first record for the western coast of the americas. even if the record is far from the previously known locations for the species it does not represent a new record regarding temperature, precipitation and topographic parameters. since "ca. r. amblyommii" antibodi ... | 2016 | 27616774 |
| rickettsia spp. among wild mammals and their respective ectoparasites in pantanal wetland, brazil. | the genus rickettsia comprises obligatory intracellular bacteria, well known to cause zoonotic diseases around the world. the present work aimed to investigate the occurrence of rickettsia spp. in wild animals, domestic dogs and their respective ectoparasites in southern pantanal region, central-western brazil, by molecular and serological techniques. between august 2013 and march 2015, serum, whole blood and/or spleen samples were collected from 31 coatis, 78 crab-eating foxes, seven ocelots, 4 ... | 2018 | 29111373 |
| isolation of rickettsia amblyommatis in huvec line. | rickettsia amblyommatis, formerly named rickettsia amblyommii and 'candidatus rickettsia amblyommii' is an intracellular bacterium belonging to the spotted fever group rickettsia. it is highly prevalent in amblyomma americanum and in other amblyomma spp. throughout the western hemisphere. r. amblyommatis has been cultivated in chicken fibroblast, primary embryonated chicken eggs, vero cells and arthropod-derived cells. because of the affinity of rickettsiae to invade vascular endothelial cells, ... | 2018 | 29321939 |
| molecular detection and identification of rickettsia species in ticks (acari: ixodidae) collected from belize, central america. | little is known about tick-borne rickettsial pathogens in belize, central america. we tested ixodid ticks for the presence of rickettsia species in three of the six northern and western belizean districts. ticks were collected from domestic animals and tick drags over vegetation in 23 different villages in november 2014, february 2015, and may 2015. a total of 2,506 collected ticks were identified to the following species: dermacentor nitens neumann (46.69%), rhipicephalus sanguineus (latreille) ... | 2017 | 28981693 |