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an assessment of host resistance to ticks on cross-bred cattle in burundi.groups of cattle of four different cross-breeds (ankole x friesian, ankole x brown-swiss, ankole x guernsey, ankole x sahiwal) plus a group of pure ankole cattle were immunized against tick-borne diseases: east coast fever, using a theileria parva trivalent vaccine, and anaplasmosis, babesiosis and, subsequently, heartwater. with the exception of two small subgroups of ankole and ankole x sahiwal which were treated by weekly spraying using delnav, all the groups were exposed to natural field cha ...19968834737
adult ixodid ticks on two cattle breeds in the south-western free state, and their seasonal dynamics.a study was conducted to compare the species of adult ixodid ticks on friesian and bonsmara cattle and their seasonal dynamics. between five and ten animals of each breed were kept on natural false upper karoo vegetation, typical of the south-western free state. between may 1990 and october 1991, the animals were examined once or twice a month for the presence of adult ticks which were removed, counted and identified. six species of ixodid ticks were recorded. the species composition on the two ...19968848299
a sero-epidemiological survey of equine piroplasmosis in the northern and eastern cape provinces of south africa.serum samples from yearling thoroughbred horses (n = 176) in the magisterial districts of colesberg, venterstad, and wodehouse in the northern and eastern cape provinces were collected between september and november 1995 to determine the prevalence of antibodies to babesia equi and babesia caballi in these regions. samples were examined for specific antibodies using the indirect fluorescent antibody test. the 95% confidence intervals for the prevalence of serum antibodies in the 3 districts comb ...19969284032
detection of theileria annulata by the pcr in ticks (acari:ixodidae) collected from cattle in mauritania.we report on the detection of theileria annulata in infected hyalomma ticks by the pcr using primers derived from the gene encoding the 30 kda major merozoite surface antigen (tamsi-1). no inhibition of the pcr was observed and as little as 0.1 pg of parasite dna, corresponding to 12 sporozoites, could be detected in non-infected tick dna samples, spiked with t. annulata genomic dna. hyalomma dromedarii ticks, fed on a calf experimentally infected with t. annulata, were used to validate the pcr ...19979203350
predation of livestock ticks by chickens as a tick-control method in a resource-poor urban environment.the possible use of chickens as predators of livestock ticks was studied. chickens were allowed to scavenge for 3 h among tick-infested cattle in a typical township backyard during the milking period. boophilus decoloratus, hyalomma marginatum rufipes, rhipicephalus evertsi evertsi and otobius megnini were recovered from the crops and gizzards at necropsy. the numbers of ticks ingested ranged from 0-128, with an average of 28.81 (+/- 8.42) per chicken. this study has confirmed that chickens are ...19979551478
dynamics of free-living ixodid ticks on a game ranch in the central province, zambia.free-living ixodid ticks were collected at monthly intervals from january to december 1996 by dragsampling the vegetation of mtendere game ranch in the chisamba district of the central province, zambia. ticks belonging to 11 species were recovered. rhipicephalus appendiculatus was most abundant, comprising 90% of the total number collected. all life stages of this tick showed a definite seasonal pattern of activity. the adults were present mainly during the rainy season (february and march), the ...19989629590
a survey of the ixodid ticks parasitising cattle in the eastern province of zambia.the results of tick surveys carried out in the eastern province of zambia between december 1982 and february 1996 were principally in agreement with the findings of earlier surveys conducted during the period 1965-72. boophilus decoloratus has almost been replaced by boophilus microplus. hyalomma truncatum was found in small numbers throughout the province and hyalomma marginatum rufipes was only rarely encountered in collections made from cattle. rhipicephalus evertsi evertsi was largely confin ...19989737594
isolation and characterization of a babesia species from rhipicephalus evertsi evertsi ticks picked off a sable antelope (hippotragus niger) which died of acute babesiosis.transmission of a babesia species to susceptible cattle by rhipicephalus evertsi evertsi ticks picked off a sable which died of acute babesiosis is described. the parasite was initially isolated by feeding r. e. evertsi ticks on a susceptible, splenectomised bovine which developed parasitaemia. blood stabilate from the parasitaemic bovine produced a fatal babesiosis in a spleen--intact bovine. clinical signs shown by the affected animals corresponded with those of acute babesiosis. parasitologic ...19989741050
ixodid tick infestations of wild birds and mammals on a game ranch in central province, zambia.ticks were collected at irregular intervals from december 1995 to november 1996 from wildlife on mtendere game ranch in the chisamba district of central province, zambia. total collections were made from two species of ground-nesting birds and 20 species of small and large mammals. thirteen species/subspecies of ixodid ticks were recovered. rhipicephalus appendiculatus was the most abundant, followed by boophilus decoloratus and rhipicephalus evertsi evertsi. small numbers of immature ticks of o ...19989741055
distinguishing species and populations of rhipicephaline ticks with its 2 ribosomal rna.most populations and some species of ticks of the genera boophilus (5 spp.) and rhipicephalus (ca. 75 spp.) cannot be distinguished phenotypically. moreover, there is doubt about the validity of species in these genera. i studied the entire second internal transcribed spacer (its 2) rrna of 16 populations of rhipicephaline ticks to address these problems: boophilus microplus from australia, kenya, south africa and brazil (4 populations); boophilus decoloratus from kenya; rhipicephalus appendicul ...19989794625
tick diversity, abundance and seasonal dynamics in a resource-poor urban environment in the free state province.the objectives of this study were to determine the diversity, seasonal dynamics and abundance of ticks infesting cattle in urban, small-scale farming communities in and around botshabelo and thaba nchu in the eastern free state province, south africa. a total of ten cattle, ear-tagged for individual identification, were investigated monthly at each of five localities. adult ticks were removed from the right hand side of each animal and placed in containers filled with 70% ethanol. they were subs ...199810192844
evidence to show that an agent that cross-reacts serologically with cowdria ruminantium in zimbabwe is transmitted by ticks.the serological diagnosis of heartwater based on reactions to the immunodominant cowdria ruminantium major antigen protein-1 (map-1) is impaired by the detection of false-positive reactions. in this study, the prevalence of false-positive reactions on seven heartwater-free farms in zimbabwe was determined to be 8-94% by immunoblotting against c. ruminantium antigens. the highest prevalence of false-positives on spring valley farm correlated with the presence of rhipicephalus evertsi evertsi tick ...19989493330
population dynamics of ticks on indigenous cattle in a pastoral dry to semi-arid rangeland zone of uganda.studies on seasonality and population dynamics of ticks on indigenous cattle and their crosses (calves) were carried out in buruli ranching scheme, nabiswera, luwero district of uganda on three treatment groups of animals: group 1 (twice a week dipping), group 2 (once a month dipping) and group 3 (no tick control). during this study, four major species of ticks of economic importance were recorded in decreasing order of abundance: rhipicephalus appendiculatus, rhipicephalus evertsi evertsi, ambl ...199910353189
[experimental transmission of crimean-congo hemorrhagic fever virus by rhipicephalus evertsi evertsi (acarina:ixodidae)].we have conducted experiments to assess the ability of rhipicephalus evertsi evertsi tick to transmit the crimean-congo haemorrhagic fever (cchf) and determine their reproductive cycle. the rh. e. evertsi was infected by intracoelomic (transparietal and intra-anal) inoculation during the imaginal stases and by oral feeding on an infected viremic goat during imaginal and nymphal stases. the infection rate, transovarial and trans-stasial cchf virus transmission were monitored for virus reisolation ...199910472436
spatial and temporal distributions of parasites: can wild and domestic ungulates avoid african tick larvae?infestation of a new host is a crucial stage in the life-cycle of parasites, and the possibility that hosts avoid infesting contact depends, in part, on the predictability of infestation risk. immature free stages of ticks (acari, ixodidae) have limited mobility and survival in the vegetation and strongly depend on host behaviours for their infestation. we studied spatial and temporal distributions of the larvae of 2 major groups of african risk species in a ranch in zimbabwe. no difference in t ...199910599078
detection and micro-scale isolation of a low molecular mass paralysis toxin from the tick, argas (persicargas) walkerae.this study describes the isolation of a 11 kda paralysis toxin from crude larval extracts of argas (persicargas) walkerae by exploiting the cross-reactivity of a monoclonal antibody (4b12), directed against the paralysis toxin of rhipicephalus evertsi evertsi. this low molecular mass is in contrast to previous findings of a 60-70 kda toxin for a. (p.) walkerae, but is similar to neurotoxins isolated from venomous forms of the class arachnida, which comprise the orders araneae (spiders). scorpion ...200011201354
analysis of the systematic relationships among ticks of the genera rhipicephalus and boophilus (acari: ixodidae) based on mitochondrial 12s ribosomal dna gene sequences and morphological characters.a portion of mitochondrial 12s rdna sequences (337-355 base pairs) and 63 morphological characters of 36 hard-tick species belonging to 7 genera were analyzed to determine the phylogenetic relationships among groups and species of rhipicephalus and between the genera rhipicephalus and boophilus. molecular and morphological data sets were first examined separately. the molecular data were analyzed by maximum parsimony (mp), maximum likelihood, and neighbor-joining distance methods; the morphologi ...200111227901
tick infestation of borana cattle in the borana province of ethiopia.a study was conducted to identify and determine burdens of ticks infesting borana cattle in the borana province of ethiopia. rhipicephalus pulchellus, rhipicephalus pravus, rhipicephalus muhsamae, rhipicephalus praetextatus, rhipicephalus evertsi evertsi, amblyomma gemma, amblyomma variegatum, amblyomma cohaerens, amblyomma lepidum, hyalomma truncatum, hyalomma marginatum rufipes and boophilus decoloratus were identified on the cattle. their burdens ranged from 658-1,554 with a mean of 1,205 tic ...200111403429
dermatophilus congolensis infection in goats in tanzania.when goats in eastern tanzania were screened for skin diseases, dermatophilus congolensis was isolated from the skin lesions in 8 of 484 animals examined. in one severely affected case, the disease was also characterized by histological studies (gram stain, giemsa stain and routine he studies) and electron microscopy. the histological picture was characterized by hyperkeratosis, parakeratosis, acanthosis, folliculitis and an inflammatory cellular reaction involving the epidermis. gram stain and ...200111556616
influence of sheep breed and application site on the efficacy of a flumethrin pour-on formulation against ticks.the objectives of this study were to determine the influence of application site and sheep breed on the efficacy of a flumethrin (1% m/v) solution for the control of 'bont'-legged (hyalomma spp.) and red-legged ticks (rhipicephalus evertsi evertsi). this study was conducted from november 1996 to february 1997 on 3 farms in the southwestern free state province. two trials were conducted on dorper sheep and 2 on merino sheep. for each specific application 30 sheep were selected and allocated to 3 ...200111811701
the distribution of ixodid ticks (acari: ixodidae) in central ethiopia.ixodid ticks were collected from domestic animals, mainly cattle, in 11 administrative zones covering 84 districts in central ethiopia over a period of 2 years (july 1996 to june 1998). nineteen tick species were identified. four of these belonged to the genus amblyomma, one to boophilus, two to haemaphysalis, three to hyalomma and nine to rhipicephalus. amblyomma variegatum and rhipicephalus evertsi evertsi were present in all 11 administrative zones and, with the exception of afar, boophilus d ...200112026058
ixodid ticks on indigenous goats owned by small-scale farmers in four communal grazing areas in south africa.indigenous goats belonging to small-scale farmers in 4 communal grazing areas in south africa were sampled for ixodid ticks during the period september 1991 to may 1993. three of these areas were in the north west province (rietgat, madinyane and bethany), and one in mpumalanga province (geluk). no tick control was practised unless requested by the owners. seven ixodid tick species, of which the majority were immature ticks, were collected from the goats in north west province. amblyomma hebraeu ...200212088070
seasonal abundance of adult ixodid ticks infesting cattle belonging to resource-limited farmers in the north-eastern free state province of south africa.a study was undertaken to determine the seasonal abundance of the ticks infesting cattle owned by resource-limited farmers in the north-eastern free state province of south africa. infestations of boophilus decoloratus koch, 1844, rhipicephalus evertsi evertsi neumann, 1897, rhipicephalus follis donitz, 1910, rhipicephalus gertrudae feldman-muhsam, 1960 and rhipicephalus warburtoni walker & horak, 2000, were monitored on cattle of mixed breeds at monthly intervals from may 1998 to april 1999. hi ...200212092776
introduced ticks and tick-borne diseases: the threat and approaches to eradication.exotic tick species and tick-borne diseases are serious threats to live-stock, companion animals, and wildlife in the united states. recurring introductions of exotic tick species into the united states are a significant indicator of the degree of risk. successful tick-eradication campaigns, such as the national program that eradicated boophilus annulatus and b. microplus from the united states, the cattle fever tick eradication program of the us department of agriculture's veterinary services t ...200212442574
ixodid ticks on cattle belonging to small-scale farmers at 4 communal grazing areas in south africa.ixodid ticks were collected during the period september 1991 to august 1993 from cattle belonging to small-scale farmers utilising 4 communal grazing areas. three of these were in north west province and 1 in mpumalanga province, south africa. ten tick species were collected in north west province and 7 in mpumalanga. the adults of amblyomma hebraeum, rhipicephalus appendiculatus and rhipicephalus evertsi evertsi were most numerous in north west province, while in mpumalanga boophilus decoloratu ...200212515294
ticks and tick-borne diseases of livestock belonging to resource-poor farmers in the eastern free state of south africa.the paper provides a summary of three studies conducted in the eastern free state of south africa between 1998 and 2000. in a questionnaire-based study approximately 21% of interviewed resource-poor farmers (n = 150) indicated that they experienced problems with ticks and tick-borne diseases. about 56% of farmers indicated that tick-related problems were most severe in summer, while 32% indicated that the most problems were encountered in winter. about 12% indicated that the tick problems were e ...200214570134
seasonal fluctuation of parasitic infestation in donkeys (equus asinus) in oodi village, kgatleng district, botswana.during the period march to september 2000, a study was conducted in oodi village, kgatleng district, botswana, to investigate the seasonal fluctuation of internal, external and blood parasites of donkeys. twelve adult donkeys were randomly selected from a farmer with a herd of 15 donkeys. monthly visits were made to the farmer when the donkeys were examined for parasites. the only ectoparasites recovered from the donkeys were instars of various tick species. the most prevalent tick was rhipiceph ...200312836744
a sero-epidemiological survey of blood parasites in cattle in the north-eastern free state, south africa.a survey to determine the incidence of parasites in cattle (n = 386) was conducted in the north eastern free state between august 1999 and july 2000. giemsa-stained blood smears were negative for blood parasites. a total of 94% of the cattle were sero-positive for babesia bigemina by indirect fluorescent antibody test while 87% were sero-positive for anaplasma by enzyme-linked immunosorbent assay. the observation of negative blood smears but high incidence of positive serological results for ana ...200415185577
crimean-congo hemorrhagic fever, mauritania.from february to august 2003, 38 persons were infected with crimean-congo hemorrhagic fever (cchf) virus in mauritania; 35 of these persons were residents of nouakchott. the first patient was a young woman who became ill shortly after butchering a goat. she transmitted the infection to 15 persons in the hospital where she was admitted and four members of her family. in nouakchott, two disease clusters and 11 isolated cases were identified. the case-fatality ratio was 28.6%. of the patients not i ...200415663851
preliminary survey of ticks (acari: ixodidae) on cattle in northern sudan.in a cross sectional survey conducted during the period june 2001 to july 2002, the geographical distribution of ticks on cattle in the sudan was determined. seventeen locations were surveyed from northern, central, eastern, western, blue nile and white nile provinces. total body collections of ticks were made from 20 cattle at each location. four tick genera and 11 species were identified. the tick species collected included amblyomma lepidum, amblyomma variegatum, boophilus decoloratus, hyalom ...200415732459
transstadial and intrastadial experimental transmission of ehrlichia canis by male rhipicephalus sanguineus.the acquisition and transmission of rickettsial pathogens by different tick developmental stages has important epidemiological implications. the purpose of this study was to determine if male rhipicephalus sanguineus can experimentally acquire and transmit ehrlichia canis in the absence of female ticks. two trials were performed where nymphal and male r. sanguineus were simultaneously acquisition fed on the same infected donor hosts, and transstadially or intrastadially exposed male ticks were f ...200515941624
prevalence of theileriosis in red hartebeest (alcelaphus buselaphus caama) in namibia.a total of 23 blood samples from red hartebeest and 28 ticks of the subspecies rhipicephalus evertsi were collected in namibia during the summer 2003. for a piroplasmida species, theileria sp 95.7% of blood and 50.0% of tick samples (all r. e. mimeticus, none of r. e. evertsi were carrying the pathogen) were pcr positive. sequencing showed infection from a re-emerging mild species of theileria phylogenetically different from other african theileria species such as theileria parva, t. buffeli, t. ...200515986252
detection of babesia canis rossi, b. canis vogeli, and hepatozoon canis in dogs in a village of eastern sudan by using a screening pcr and sequencing methodologies.babesia and hepatozoon infections of dogs in a village of eastern sudan were analyzed by using a single pcr and sequencing. among 78 dogs, 5 were infected with babesia canis rossi and 2 others were infected with b. canis vogeli. thirty-three dogs were positive for hepatozoon. hepatozoon canis was detected by sequence analysis.200516275954
some observations on ticks (acari: ixodidae) infesting sheep in river nile province of northern sudan.five species of ixodid ticks were found in a cross-sectional survey in which 200 sheep were examined for ticks in river nile province, sudan. hyalomma anatolicum anatolicum was the predominant species (73.6%), whereas ticks belonging to the rhipicephalus sanguineus group (14.7%), rhipicephalus evertsi evertsi (9.1%), rhipicephalus simus (2%) and hyalomma dromedarii (0.5%) were also found. the mean tick load was 11.2 per animal. in a subsequent longitudinal survey ticks were collected on a monthl ...200516300192
acaricide efficiency of amitraz/cypermethrin and abamectin pour-on preparations in game.the efficacy of an amitraz/cypermethrin pour-on preparation (1% w/v each) was tested against natural tick infestations of buffaloes, eland and blesbok in three separate trials. the eland were also treated with a 0.02% abamectin (w/v) acaricidal pour-on preparation. the amitraz/cypermethrin pour-on was effective against amblyomma hebraeum, rhipicephalus evertsi evertsi, rhipicephalus appendiculatus and hyalomma marginatum rufipes on the buffaloes. both acaricides were effective against r. appendi ...200516562734
ticks on crested francolins, francolinus sephaena, and on the vegetation on a farm in limpopo province, south africa.ticks were collected at approximately bi-monthly intervals between june 1996 and june 1997 from crested francolins, francolinus sephaena, and from the vegetation on a mixed cattle and wildlife farm in limpopo province, south africa. the birds were infested with the immature stages of 13 tick species, of which amblyomma hebraeum, amblyomma marmoreum and hyalomma marginatum rufipes were the most numerous and prevalent. ten ixodid tick species were collected from the vegetation, of which the immatu ...200516562738
a secondary structural common core in the ribosomal its2 (internal transcribed spacer) of culexspecies from diverse geographical locations.in the present study, sequence and structural analysis of its2 region (the spacer segment between 5.8s and 28s rrna of mature rrna sequences) of 7 culex species belonging to 5 different geographical locations was carried out. alignment of the its2 sequence from the 7 species revealed 8 homologous domains. four species namely c. vishnui, c. annulus, c. pipiens, c. quiquefasciatusshowed high sequence (98-100%) and rna secondary structure similarity. the its2 similarity among different species is h ...200517597853
the use of a pour-on and spray dip containing amitraz to control ticks (acari: ixodidae) on cattle.knockdown and persistence efficacies of a pour-on containing amitraz 1% and cypermethrin 1% and a spray dip containing 12.5% amitraz were compared. knock-down and persistence efficacies of the amitraz spray dip against rhipicephalus (boophilus) decoloratus and amblyomma hebraeum were significantly higher for the duration of the trial than those of the pour-on. in the case of rhipicephalus appediculatus and rhipicephalus evertsi evertsi, efficacy was significantly higher on days 2 and 5. resistan ...200617120621
ehrlichia ruminantium variants which do not cause heartwater found in south africa.in 1994 a batch of apparently healthy goats was selected for intended export to the usa from a heartwater-free and vector tick-free region of south africa. the animals were tested serologically for heartwater, using either or both an ifa and an elisa test, and 52% were found to be serologically positive. a pcr assay based on ehrlichia ruminantium 16s gene sequences gave positive results for 54% of the animals, suggesting that apparently non-pathogenic e. ruminantium variants existed in this hear ...200717123750
detection of rickettsia africae in rhipicephalus (boophilus) decoloratus ticks from the republic of botswana, south africa.a total of 53 engorged adult ticks belonging to the species rhipicephalus (boophilus) decoloratus (n = 9), rhipicephalus evertsi evertsi (n = 27), rhipicephalus appendiculatus (n = 9), amblyomma hebraeum (n = 5), and hyalomma marginatum turanicum (n = 3), were removed from oryx in botswana (south africa). they were tested for the presence of spotted fever group (sfg) rickettsia and anaplasma phagocytophilum using polymerase chain reaction (pcr). seventy-seven percent of r. decoloratus as well as ...200717690416
goats as alternative hosts of cattle ticks.the objective of this study was to compare the presence on goats and cattle of adult ticks that usually infest cattle. to this end ticks collected from sets of five goats were compared with those collected from sets of five cattle at 72 communal dip-tanks in the eastern region of the eastern cape province. amblyomma hebraeum was present on goats at 25 and on cattle at 39 dip-tanks, and a total of 61 goats and 138 cattle were infested. adult rhipicephalus (boophilus) microplus was present on goat ...200717708147
ticks associated with the three largest wild ruminant species in southern africa.the objective of this study was to assess the host status of the three largest southern african wild ruminants, namely giraffes, giraffa camelopardalis, african buffaloes, syncerus caffer, and eland, taurotragus oryx for ixodid ticks. to this end recently acquired unpublished data are added here to already published findings on the tick burdens of these animals, and the total numbers and species of ticks recorded on 12 giraffes, 18 buffaloes and 36 eland are summarized and discussed. twenty-eigh ...200717933365
distribution and population dynamics of ticks (acari: ixodidae) infesting sheep in sennar state, sudan.a cross-sectional survey of ticks infesting sheep was conducted in sennar state, sudan. a total body collection of ticks was carried out at five localities sennar town, singa, dinder, abu naama and um banein on two types of desert sheep (watish and ashgar) on two farms at each locality at two monthly intervals for one year starting july 2002 to may 2003. four tick genera and eight species were identified. they were amblyomma lepidum, hyalomma anatolicum anatolicum, hyalomma truncatum, rhipicepha ...200718453239
identification of a novel babesia sp. from a sable antelope (hippotragus niger harris, 1838).babesiosis in a sable antelope (hippotragus niger harris, 1838) was first reported in 1930; the parasite was named babesia irvinesmithi. recently, specimens from an adult sable that presented with a sudden onset of disease and that subsequently died during immobilization were submitted for molecular characterization. microscopic examination of thin blood smears revealed the presence of small piroplasms. dna was extracted from blood samples; the v4 variable region of the 18s rrna gene was amplifi ...200818508943
reliminary survey of ticks (acari: ixodidae) on cattle in central equatoria state, southern sudan.in a preliminary survey conducted in 2005, the species composition and seasonality of ticks infesting cattle in central equatoria state, southern sudan was determined. three locations were selected (gumbo, khor rumla and nyaing) and surveyed every 3 months. two cattle herds in each of the three locations were visited four times during the study period. total body collections of ticks were made from each of five cattle (nilotic zebu breed) kept in six different herds. four tick genera and ten spe ...200818575063
protection of metarhizium anisopliae conidia from ultra-violet radiation and their pathogenicity to rhipicephalus evertsi evertsi ticks.metarhizium anisopliae conidia were formulated in water or in olive oil containing 3% commercial sunscreens (everysun or e45 sun block 50) and exposed to an artificial uv source for up to 5 hours. survival of conidia after 5 h of exposure to uv in oil formulation was 29% when protected with everysun, 40% when protected with e45, and 4% in control. in comparison, survival of conidia formulated in water was 13% when protected with everysun, 24% when protected with e45, and 0% in control. furthermo ...200818712608
the prevalence of serum antibodies to ehrlichia ruminantium infection in ranch cattle in tanzania: a cross-sectional study.serum samples collected in a cross-sectional survey of grazing cattle on manyara ranch, monduli district, tanzania, were tested by indirect major antigenic protein 1 fragment b (map 1-b) elisa to determine the seroprevalence of ehrlichia ruminantium and to assess ranch-level risk factors for heartwater. heartwater-exposed cattle were widespread on the ranch and overall seroprevalence was 50.3% (95% ci, 44.9-55.6), enough to indicate an endemically unstable situation. multivariate logistic regres ...200818846851
host surveys, ixodid tick biology and transmission scenarios as related to the tick-borne pathogen, ehrlichia canis.the ehrlichioses have been subject to increasing interest from veterinary and public health perspectives, but experimental studies of these diseases and their etiologic agents can be challenging. ehrlichia canis, the primary etiologic agent of canine monocytic ehrlichiosis, is relatively well characterized and offers unique advantages and opportunities to study interactions between a monocytotropic pathogen and both its vertebrate and invertebrate hosts. historically, advances in tick-borne dise ...200818963493
ixodid ticks infesting domestic goats in communal land areas of zimbabwe.the purpose of this study was to determine the species spectrum of ticks infesting goats owned by resource-limited farmers in the state-owned communal land areas of zimbabwe. ticks were collected from goats at a single locality within each of 5 communal land areas, and a total of 14 ixodid tick species was recovered. the most numerous tick was rhipicephalus evertsi evertsi, which was present in all areas at each sampling, and a rhipicephalus sp. (near r. punctatus), which was most abundant on go ...200819244819
the extent of acaricide resistance in 1-, 2- and 3-host ticks on communally grazed cattle in the eastern region of the eastern cape province, south africa.in order to determine the extent of acaricide resistance in the eastern region of the eastern cape province 1-, 2- and 3-host ticks were collected from cattle at 59 dip-tanks over a period of 2 years. these ticks were tested for resistance against 3 compounds, namely amitraz, cypermethrin and chlorfenvinphos. the shaw larval immersion test detected emerging resistance to amitraz in rhipicephalus (boophilus) microplus at 2 dip-tanks and resistance at a 3rd. it also revealed resistance in this tic ...200819244821
species composition and geographic distribution of ticks infesting cattle, goats and dogs in a temperate and in a subtropical region of south-east africa.the species and distribution of ticks infesting cattle, goats and dogs in the eastern region of the eastern cape province, south africa and maputo province, mozambique were determined from collections made from these animals at 72 localities in the former region and 30 in the latter. eleven ixodid and one argasid species were recovered in the eastern cape province and 15 ixodid species in maputo province. the most common ticks infesting cattle and goats in both provinces were amblyomma hebraeum, ...200921105593
poxvirus protein evolution: family wide assessment of possible horizontal gene transfer events.to investigate the evolutionary origins of proteins encoded by the poxviridae family of viruses, we examined all poxvirus protein coding genes using a method of characterizing and visualizing the similarity between these proteins and taxonomic subsets of proteins in genbank. our analysis divides poxvirus proteins into categories based on their relative degree of similarity to two different taxonomic subsets of proteins such as all eukaryote vs. all virus (except poxvirus) proteins. as an example ...200919464330
the comparative prevalence of five ixodid tick species infesting cattle and goats in maputo province, mozambique.this study compares the prevalence of ixodid tick species on cattle and goats in maputo province. adult ticks as well as the nymphs of three species, and only the adults of two species were collected from sets of five cattle at 21 localities throughout the province and compared with those collected from similar sets of goats at the same places. amblyomma hebraeum adults and/or nymphs were present on cattle and on goats at all 21 localities, and 90 cattle and 22 goats were infested with adult tic ...200920698440
tick infestation, and udder and teat damage in selected cattle herds of matabeleland south, zimbabwe.a cross-sectional survey was conducted to determine tick infestation, and udder and teat damage in 286 lactating cows and heifers at six properties in the smallholder and commercial sectors in gwanda district of matabeleland south province, zimbabwe. eight tick species were identified: amblyomma hebraeum, hyalomma truncatum, hyalomma marginatum rufipes, rhipicephalus evertsi evertsi, rhipicephalus (boophilus) decoloratus, rhipicephalus appendiculatus, rhipicephalus zambeziensis and rhipicephalus ...200920698443
tick-borne rickettsioses, neglected emerging diseases in rural senegal.rickettsioses are one of the most important causes of systemic febrile illness among travelers from developed countries, but little is known about their incidence in indigenous populations, especially in west africa.201020856858
tick loads in cattle raised on sweet and sour rangelands in the low-input farming areas of south africa.the objective of this study was to compare tick loads and prevalence in nguni and non-descript cattle in the sweet (palatable throughout the year) and sour (palatable only in the rainy season) communal rangelands of the eastern cape province, south africa. engorged adult female ixodid ticks were collected and identified seasonally from 144 cattle raised on sweet and sour rangelands from august 2007 to april 2008. three tick species were identified in the sweet and sour rangelands namely rhipicep ...201020967568
coxiella burnetii in humans and ticks in rural senegal.q fever is a worldwide zoonotic disease caused by coxiella burnetii. epidemiologically, animals are considered reservoirs and humans incidental hosts.201020386603
survey of ixodid ticks in domestic ruminants in bedelle district, southwestern ethiopia.a survey aimed at determining the status of ticks in cattle, sheep and goats in bedelle district (southwestern ethiopia) was carried out from november 2007 to april 2008. out of the total 330 animals examined, 314 (95.2%) were found to be infested (harbouring of at least a single tick). high rates of infestations were recorded across all three host species. factors like month of collection, age and sex of host species did not show significant association with infestation rates. a total of 5,507 ...201020563884
bm86 homologues and novel ataq proteins with multiple epidermal growth factor (egf)-like domains from hard and soft ticks.tick control on livestock relies principally on the use of acaricides but the development of acaricide resistance and concerns for environmental pollution underscore the need for alternative control methods, for instance through the use of anti-tick vaccines. two commercial vaccines based on the recombinant bm86 protein from rhipicephalus (boophilus) microplus ticks were developed. partial protection of the bm86 vaccine against other rhipicephalus (boophilus) and hyalomma tick species suggests t ...201020647015
ticks on pastures and on two breeds of cattle in the eastern cape province, south africa.many studies on the population dynamics of questing ticks on pastures and of parasitic ticks on cattle have been conducted. few, however, have attempted to link the two in a single study. this study aimed to assess the population dynamics of questing ixodid ticks on pastures and of adult ticks on two breeds of cattle with different levels of susceptibility to tick infestation on the same pastures. between january 2005 and december 2009 questing ixodid ticks were collected monthly from natural pa ...201123327215
the dynamics of questing ticks collected for 164 consecutive months off the vegetation of two landscape zones in the kruger national park (1988-2002). part iii. the less commonly collected species.despite many studies regarding tick ecology, limited information on long-term changes in tick populations exist. this study assessed the long-term population dynamics of the less frequently collected questing ixodid ticks in the kruger national park (knp). from 1988 to 2002, monthly dragging of the vegetation was performed in three habitats (grassland, woodland and gully) at two sites in the knp (nhlowa road, landscape zone 17, and skukuza, landscape zone 4). amblyomma marmoreum and rhipicephalu ...201123327206
tick paralysis in australia caused by ixodes holocyclus neumann.ticks are obligate haematophagous ectoparasites of various animals, including humans, and are abundant in temperate and tropical zones around the world. they are the most important vectors for the pathogens causing disease in livestock and second only to mosquitoes as vectors of pathogens causing human disease. ticks are formidable arachnids, capable of not only transmitting the pathogens involved in some infectious diseases but also of inducing allergies and causing toxicoses and paralysis, wit ...201121396246
colonization of grande comore island by a lineage of rhipicephalus appendiculatus ticks.union of the comoros suffered a severe east coast fever epidemic in 2004. rhipicephalus appendiculatus was probably involved in pathogen transmission as this competent tick species, although previously absent from comoros, was sampled on 4 animals on one geographical site during the epidemic. we carried out an entomological survey on all three islands of union of the comoros to establish cattle tick species distribution with a special emphasis on r. appendiculatus. we investigated r. appendicula ...201121414194
prevalence and species composition of ixodid ticks infesting horses in three agroecologies in central oromia, ethiopia.a cross-sectional study was conducted to determine the species composition and prevalence of ixodid ticks infesting horses in three agroecological zones in central ethiopia. for this purpose, a total of 1,168 horses were examined for tick infestation. an overall prevalence of 39.04% of tick infestation on horses was recorded. a total of 917 adult ticks were collected from infested horses. amblyomma, boophilus, rhipicephalus, and hyalomma genera with the respective prevalence of 3.2%, 1.8%, 29.2% ...201121656133
control of tick populations by spraying metarhizium anisopliae conidia on cattle under field conditions.conidia of the entomopathogenic fungus, metarhizium anisopliae, in oil/water formulation (1-á+ù-á10(8) conidia/ml) were sprayed at 3-áweekly intervals on rhipicephalus evertsi evertsi and rhipicephalus (boophilus) decoloratus ticks while feeding on afrikana bulls grazing in paddocks for a period of 1-áyear. the fungus reduced the on-host tick populations by 83% 3-ámonth after commencement of the experiment. the formulation by itself had only minimal effect on the tick population. tick population ...201121725837
an elisa to detect serum antibodies to the salivary gland toxin of ixodes holocyclus neumann in dogs and rodents.the ixodes holocyclus tick causes paralysis in up to 10,000 companion and domestic animals each year in australia. treatment requires the removal of the parasite and the administration of a commercial tick antiserum that is prepared from hyperimmune dogs. each batch of this serum is initially tested for toxin-neutralising potency in a mouse bioassay that is expensive, time consuming, and subjective. with the aim of developing a rapid in vitro assay to replace the bioassay, we used a partially pu ...201121687655
relationships between tick counts and coat characteristics in nguni and bonsmara cattle reared on semiarid rangelands in south africa.indigenous nguni cattle are adapted to the semiarid rangeland and appear to be resistant to ticks; however, the mechanism for tick resistance is yet to be established. to understand tick resistance in cattle, relationships among skin thickness, hair length, coat score, and tick counts were estimated in nguni (n=12) and bonsmara (n=12) heifers on semiarid rangelands of south africa. the tick species observed to infest the heifers were rhipicephalus (boophilus) decoloratus (frequency: 76%), rhipic ...201121890073
tick cell lines for study of crimean-congo hemorrhagic fever virus and other arboviruses.abstract continuous cell lines derived from many of the vectors of tick-borne arboviruses of medical and veterinary importance are now available. their role as tools in arbovirus research to date is reviewed and their potential application in studies of tick cell responses to virus infection is explored, by comparison with recent progress in understanding mosquito immunity to arbovirus infection. a preliminary study of propagation of the human pathogen crimean-congo hemorrhagic fever virus (cc ...201121955214
ticks (acari: ixodidae) infesting cattle and african buffaloes in the tsavo conservation area, kenya.several ixodid tick species are shared between domestic cattle and african buffaloes (syncerus caffer). so too, are a number of tick-borne diseases. the aim of the study was to compare the species composition of ticks that infest cattle and buffaloes utilising the same habitat within the tsavo conservation area, kenya. to this end, 25 cattle and 62 buffaloes were each opportunistically sampled for ticks on a single occasion in february 2010. eight species, namely amblyomma gemma, amblyomma lepid ...201223327329
ectoparasites of sheep in three agro-ecological zones in central oromia, ethiopia.a cross-sectional study was conducted to determine the prevalence and risk factors for ectoparasites infestation in sheep in three agro-ecological zones in central oromia, ethiopia, from october 2009 to april 2010. the study revealed that 637 (48.1%) of the 1325 sheep examined were infested with one or more ectoparasites. the ectoparasites identified were bovicola ovis (27.2%), melophagus ovinus (16.4%), ctenocephalides sp. (2.3%), linognathus africanus (1.2%), linognathus ovillus (0.3%), sarcop ...201223327319
epidemiological perspectives of ticks and tick-borne diseases in south sudan: cross-sectional survey results.a cross-sectional study was conducted between september and october 2010 in five states of south sudan that were selected on the basis of the perceived risk of tick-borne diseases. the purpose was to investigate epidemiological parameters of tick-borne diseases in south sudan and their uses in future control strategies. a total of 805 calves were assessed by clinical, microscopic and serological examination and tick counts. the indirect enzyme-linked immuno-sorbent assay (elisa) was used to dete ...201223327317
theileriosis (cytauxzoonosis) in roan antelope (hippotragus equinus): field exposure to infection and identification of potential vectors.four hand-reared, naïve roan antelope, 4 months of age, were exposed to naturally infected pasture on a game farm in mpumalanga province, south africa, where roan are known to die from theileriosis. various clinical parameters were recorded during this period. the predominant ticks parasitising these animals at the time (january to february), were rhipicephalus appendiculatus and rhipicephalus evertsi evertsi adults. after a period of 5 weeks the animals developed signs of clinical theileriosis ...201223327309
gene silencing in tick cell lines using small interfering or long double-stranded rna.gene silencing by rna interference (rnai) is an important research tool in many areas of biology. to effectively harness the power of this technique in order to explore tick functional genomics and tick-microorganism interactions, optimised parameters for rnai-mediated gene silencing in tick cells need to be established. ten cell lines from four economically important ixodid tick genera (amblyomma, hyalomma, ixodes and rhipicephalus including the sub-species boophilus) were used to examine key p ...201222773071
pathogen prevalence in ticks collected from the vegetation and livestock in nigeria.ticks are important disease vectors that can cause considerable economic losses by affecting animal health and productivity, especially in tropical and subtropical regions. in this study, we investigated the prevalence and diversity of bacterial and protozoan tick-borne pathogens in ticks collected from the vegetation and cattle in nigeria by pcr. the infection rates of questing ticks were 3.1% for rickettsia species, 0.1% for coxiella burnetii and 0.4% for borrelia species. other pathogens, suc ...201222327584
tick infestation patterns in free ranging african buffalo (syncercus caffer): effects of host innate immunity and niche segregation among tick species.ticks are of vast importance to livestock health, and contribute to conflicts between wildlife conservation and agricultural interests; but factors driving tick infestation patterns on wild hosts are not well understood. we studied tick infestation patterns on free-ranging african buffalo (syncercus caffer), asking (i) is there evidence for niche segregation among tick species?; and (ii) how do host characteristics affect variation in tick abundance among hosts? we identified ticks and estimated ...201224533310
new data regarding distribution of cattle ticks in the south-western indian ocean islands.recent studies have produced new insight into the origin and distribution of some cattle ticks in the south-western indian ocean islands. rhipicephalus appendiculatus, introduced from tanzania in 2002, is now well established on grande comore but has not yet reached the other islands of the archipelago (mohéli, anjouan and mayotte). only one of the two clades identified in africa has settled so far. amblyomma variegatum, which was not supposed to be able to persist in the antananarivo region (13 ...201324016261
relationship between the prevalence of ectoparasites and associated risk factors in free-range pigs in kenya.a cross-sectional study was undertaken to determine the prevalence of ectoparasites and possible risk factors in free-range pigs from 135 farms of busia district, kenya. three hundred and six pigs were examined for presence of external parasites using standard parasitological methods. data on management practices including housing and history of acaricide spraying were also collected. the ectoparasites found in the pigs were haematopinus suis (96.1%), sarcoptes scabiei (63.7%), and ticks (29.7%) ...201323984085
relapsing fever borreliae in africa.the study of relapsing fever borreliae in africa has long suffered from the use of non-specific laboratory tools for the direct detection of these spirochetes in clinical and vector specimens. accordingly, borrelia hispanica, borrelia crocidurae, borrelia duttonii, and borrelia recurrentis have traditionally been distinguished on the basis of geography and vector and the unproven hypothesis that each species was exclusive to one vector. the recent sequencing of three relapsing fever borrelia gen ...201323926141
a comparison between tick species collected in a controlled and control free area on a game ranch in south africa.despite the large number of collection records, there are no recent collections of ixodid ticks of this magnitude in the waterberg area, limpopo province, south africa. free-living ticks on a commercial game farm were obtained by a total of 432 drag-samples in eight sample sites from september 2003 to august 2008. the ticks were collected to establish the difference between tick species and densities associated with acaricide-controlled (semi-intensive) and control-free areas on a game farm in t ...201323718159
molecular detection and characterization of tick-borne pathogens in dogs and ticks from nigeria.only limited information is currently available on the prevalence of vector borne and zoonotic pathogens in dogs and ticks in nigeria. the aim of this study was to use molecular techniques to detect and characterize vector borne pathogens in dogs and ticks from nigeria.201323505591
host specialization in ticks and transmission of tick-borne diseases: a review.determining patterns of host use, and the frequency at which these patterns change, are of key importance if we are to understand tick population dynamics, the evolution of tick biodiversity, and the circulation and evolution of associated pathogens. the question of whether ticks are typically host specialists or host generalists has been subject to much debate over the last half-century. indeed, early research proposed that morphological diversity in ticks was linked to host specific adaptation ...201324109592
detection of borrelia theileri in rhipicephalus geigyi from mali.disease burden within cattle is a concern around the world. bovine borreliosis, one such disease, is caused by the spirochete borrelia theileri transmitted by the bite of an infected rhipicephalus (boophilus) species tick. a number of species within the genus are capable of transmitting the agent and are found on multiple continents. cattle in the west african nation of mali are infested with four species of rhipicephalus ticks of the subgenus boophilus: rhipicephalus annulatus, rhipicephalus mi ...201424709337
identification of rickettsial pathogens in ixodid ticks in northern senegal.the spotted fevers, caused by the rickettsia bacteria, are a group of emerging diseases that are responsible for significant human morbidity. in africa, the distribution of different species of rickettsia in their tick vectors is poorly studied. we have collected 1169 hard ticks from 5 different species in the northern senegal, close to the saharan border. in a far northern collection site, corresponding to the rickettsia africae distribution area, we collected three amblyomma variegatum ticks i ...201424908548
protozoan and bacterial pathogens in tick salivary glands in wild and domestic animal environments in south africa.a total of 7364 ticks belonging to 13 species was collected from 64 game animals (belonging to 11 species) and from 64 livestock animals (cattle and sheep) living in close vicinity at 6 localities in 3 south african provinces (free state, mpumalanga, and limpopo). the geographic distribution of all tick species was congruent with the literature except for haemaphysalis silacea. from each infested host, a maximum of 10 males and 10 females of each tick species were dissected to isolate the saliva ...201424378080
molecular detection of piroplasms in ixodid ticks infesting cattle and sheep in western oromia, ethiopia.in ethiopia, ticks and tick-borne diseases are widely distributed and contribute to important economic losses. several studies investigated the prevalence and species composition of ticks infesting ruminants; however, data on tick-borne pathogens are still scarce. during the study period from october 2010 to april 2011, a total of 1,246 adult ticks and 264 nymphs were collected from 267 cattle and 45 sheep in bako district, western oromia, ethiopia. the study showed infestation of 228/267 (85.4  ...201423846769
history and development of research on wildlife parasites in southern africa, with emphasis on terrestrial mammals, especially ungulates.the history of wildlife parasitology in south africa, and to some extent southern africa, is reviewed, giving a brief overview of the early years and following its development from the founding of the onderstepoort veterinary institute in 1908 until the turn of the century. an emphasis is placed on game species. the main findings on protozoan parasites, including those of carnivores, are presented, starting in the 1890s and leading up to the first decade of the 21st century. important developmen ...201425830101
lumpy skin disease: attempted propagation in tick cell lines and presence of viral dna in field ticks collected from naturally-infected cattle.lumpy skin disease (lsd) is of substantial economic importance for the cattle industry in africa and the near and middle east. several insect species are thought to transmit the disease mechanically. recent transmission studies have demonstrated the first evidence for a role of hard (ixodid) ticks as vectors of lumpy skin disease virus (lsdv). the aim of this study was to attempt in vitro growth of the virus in rhipicephalus spp. tick cell lines and investigate in vivo the presence of the virus ...201425468765
first molecular detection of rickettsia africae in ticks from the union of the comoros.rickettsia africae is the agent of african tick bite fever, a disease transmitted by ticks in sub-saharan africa. in union of the comoros, a recent study reported the presence of a rickettsia africae vector but no information has been provided on the circulation of the pathogenic agent in this country.201425245895
are ticks venomous animals?as an ecological adaptation venoms have evolved independently in several species of metazoa. as haematophagous arthropods ticks are mainly considered as ectoparasites due to directly feeding on the skin of animal hosts. ticks are of major importance since they serve as vectors for several diseases affecting humans and livestock animals. ticks are rarely considered as venomous animals despite that tick saliva contains several protein families present in venomous taxa and that many ixodida genera ...201425006341
bunyavirus-vector interactions.the bunyaviridae family is comprised of more than 350 viruses, of which many within the hantavirus, orthobunyavirus, nairovirus, tospovirus, and phlebovirus genera are significant human or agricultural pathogens. the viruses within the orthobunyavirus, nairovirus, and phlebovirus genera are transmitted by hematophagous arthropods, such as mosquitoes, midges, flies, and ticks, and their associated arthropods not only serve as vectors but also as virus reservoirs in many cases. this review present ...201425402172
arachnids of medical importance in brazil: main active compounds present in scorpion and spider venoms and tick saliva.arachnida is the largest class among the arthropods, constituting over 60,000 described species (spiders, mites, ticks, scorpions, palpigrades, pseudoscorpions, solpugids and harvestmen). many accidents are caused by arachnids, especially spiders and scorpions, while some diseases can be transmitted by mites and ticks. these animals are widely dispersed in urban centers due to the large availability of shelter and food, increasing the incidence of accidents. several protein and non-protein compo ...201526273285
molecular detection and characterization of babesia bovis, babesia bigemina, theileria species and anaplasma marginale isolated from cattle in kenya.infections with babesia bovis, babesia bigemina, theileria species and anaplasma marginale are endemic in kenya yet there is a lack of adequate information on their genotypes. this study established the genetic diversities of the above tick-borne hemoparasites infecting cattle in kenya.201526420543
ethnoecological knowledge of ticks and treatment of tick-borne diseases among maasai people in northern tanzania.the aim of this study was to understand traditional knowledge of tick ecology and remedies for tick-borne diseases (tbds) among the maasai people in northern tanzania.201527065643
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
distribution of endemic and introduced tick species in free state province, south africa.the distributions of endemic tick vector species as well as the presence of species not endemic to free state province, south africa, were determined during surveys or opportunistic collections from livestock, wildlife and vegetation. amongst endemic ticks, the presence of rhipicephalus appendiculatus was confirmed in the north of the province, whilst rhipicephalus decoloratus was collected at 31 localities mostly in the centre and east, and ixodes rubicundus at 11 localities in the south, south ...201526244582
an update on the ecological distribution of the ixodidae ticks in zimbabwe.in total 7657 ticks were collected from 121 dip tanks in 12 districts representative of zimbabwe's five ecological regions between september 2013 and may 2014. based on morphological traits four genera and 13 species of ticks were identified. amblyomma hebraeum (60.3 %), rhipicephalus microplus (58.7 %), rhipicephalus decoloratus (47.1 %), rhipicephalus appendiculatus (56.2 %), rhipicephalus evertsi evertsi (67.8 %), rhipicephalus (near) punctatus (13.2 %), hyalomma truncatum (38 %) and hyalomma ...201525721256
faustovirus-like asfarvirus in hematophagous biting midges and their vertebrate hosts.faustovirus, a new asfarviridae-related giant virus, was recently isolated in vermamoeba vermiformis, a protist found in sewage water in various geographical locations and occasionally reported in human eye infection cases. as part of a global metagenomic analysis of viral communities existing in biting midges, we report here for the first time the identification and isolation of a faustovirus-like virus in hematophagous arthropods and its detection in their animal hosts. the dna virome analysis ...201526733117
seasonal patterns of hormones, macroparasites, and microparasites in wild african ungulates: the interplay among stress, reproduction, and disease.sex hormones, reproductive status, and pathogen load all affect stress. together with stress, these factors can modulate the immune system and affect disease incidence. thus, it is important to concurrently measure these factors, along with their seasonal fluctuations, to better understand their complex interactions. using steroid hormone metabolites from fecal samples, we examined seasonal correlations among zebra and springbok stress, reproduction, gastrointestinal (gi) parasite infections, an ...201525875647
propagation of the israeli vaccine strain of anaplasma centrale in tick cell lines.anaplasma centrale has been used in cattle as a live blood vaccine against the more pathogenic anaplasma marginale for over 100 years. while a. marginale can be propagated in vitro in tick cell lines, facilitating studies on antigen production, immunisation and vector-pathogen interaction, to date there has been no in vitro culture system for a. centrale. in the present study, 25 cell lines derived from 13 ixodid tick species were inoculated with the israeli vaccine strain of a. centrale and mon ...201526210950
laboratory diagnosis of tick-borne african relapsing fevers: latest developments.in africa, relapsing fevers caused by ectoparasite-borne borrelia species are transmitted by ticks, with the exception of borrelia recurrentis, which is a louse-borne spirochete. these tropical diseases are responsible for mild to deadly spirochetemia. cultured borrelia crocidurae, borrelia duttonii, and borrelia hispanica circulate alongside at least six species that have not yet been cultured in vectors. direct diagnosis is hindered by the use of non-specific laboratory tools. indeed, microsco ...201526618151
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