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1.
An increasing number of studies reveal that ticks and their hosts are infected with multiple pathogens, suggesting that coinfection might be frequent for both vectors and wild reservoir hosts. Whereas the examination of associations between coinfecting pathogen agents in natural host–vector–pathogen systems is a prerequisite for a better understanding of disease maintenance and transmission, the associations between pathogens within vectors or hosts are seldom explicitly examined. We examined the prevalence of pathogen agents and the patterns of associations between them under natural conditions, using a previously unexamined host–vector–pathogen system—green lizards Lacerta viridis, hard ticks Ixodes ricinus, and Borrelia, Anaplasma, and Rickettsia pathogens. We found that immature ticks infesting a temperate lizard species in Central Europe were infected with multiple pathogens. Considering I. ricinus nymphs and larvae, the prevalence of Anaplasma, Borrelia, and Rickettsia was 13.1% and 8.7%, 12.8% and 1.3%, and 4.5% and 2.7%, respectively. The patterns of pathogen prevalence and observed coinfection rates suggest that the risk of tick infection with one pathogen is not independent of other pathogens. Our results indicate that Anaplasma can play a role in suppressing the transmission of Borrelia to tick vectors. Overall, however, positive effects of Borrelia on Anaplasma seem to prevail as judged by higher-than-expected BorreliaAnaplasma coinfection rates.  相似文献   

2.
Anaplasma phagocytophilum has been first isolated from the blood of two Czech patients simultaneously with a cultivation of Borrelia burgdorferi sensu lato from their erythema migrans lesions. Cultivation of different Borrelia spp. from 12 erythema migrans biopsies, from 2 blood, one liquor and one placenta sample in BSK-H medium was successful. Adapted conventional methods targeting 16S rRNA and OspA genes for real-time polymerase chain reaction (PCR) and partial sequencing of these genes together with microscopical examinations of the blood smears provided a direct detection of the B. afzelii, B. burgdorferi, B. garinii, B. valaisiana and B. bissettii in the skin, B. garinii in the blood, placenta and liquor in 24 (36.3 %) patients, and A. phagocytophilum in 10 (15 %) patients with erythema migrans. Positive indirect IgM immunofluorescence against Anaplasma sp. was obtained in 7 cases, specific IgG antibodies were detected in 12 patients. Three women suffering from erythema migrans in the first trimester had positive PCR for Anaplasma and/or for Borrelia in the blood and two of them, later, in the placenta. Interpretation of laboratory data can bring important contribution to establishing the role of Anaplasma sp. in erythema migrans and forming the principle of precaution with laboratory diagnosis during pregnancy which always should be reflected in the resistance of Anaplasma sp. toward penicillins.  相似文献   

3.
Borrelia valaisiana-related spirochetes were detected for the first time in Ixodes granulatus ticks collected in Taiwan. The genetic identities of these detected spirochetes were determined by analyzing the gene sequences amplified by a genospecies-specific polymerase chain reaction assay based on the outer surface protein A (OspA) gene of B. burgdorferi sensu lato. Phylogenetic relationships were analyzed by comparing the sequences of OspA gene obtained from 35 strains of Borrelia spirochetes representing six genospecies of Borrelia. Eight major clades can be easily distinguished by neighbour-joining analysis and were congruent by maximum-parsimony method. Except one strain (KH-74), all these Borrelia spirochetes of Taiwan were genetically affiliated to the same clade with highly homogeneous sequences (97.8–100% similarity), and can be discriminated from other groups of B. valaisiana and other genospecies of Borrelia spirochetes with a sequence divergence ranging from 3 to 19.6%. Moreover, intraspecific analysis also revealed that three distinct groups are evident between the same species of B. valaisiana spirochetes detected in Taiwan. Our results provide the first evidence of B. valaisiana spirochetes detected in I. granulatus ticks collected in Taiwan and demonstrate that all these B. valaisiana spirochetes of Taiwan represent three major groups distinct from the European group of B. valaisiana spirochetes.  相似文献   

4.
Tick-borne bacterial zoonoses of livestock and free-ranging ungulates caused by Anaplasma spp. are common in Central Europe. The aim of this study was to analyze the prevalence of Anaplasma phagocytophilum and other tick-borne bacteria in wild animals from western Slovakia. Infection with A. phagocytophilum was recorded in 62.86% of analyzed roe deer (Capreolus capreolus), in two red deer (Cervus elaphus) and two wild boars (Sus scrofa). Dermacentor reticulatus and Ixodes ricinus ticks collected on red deer were not A. phagocytophilum-infected. However, spotted fever group rickettsiae were detected in ticks collected from red deer. High prevalence of A. phagocytophilum in roe deer as well as positive red deer and wild boars suggest the occurrence of natural foci in western Slovakia.  相似文献   

5.
In this study, we identified two Haemaphysalis species present at the Khao Yai National Park in Thailand and investigated the presence of rickettsia in these ticks. A total of 166 Haemaphysalis specimens were collected randomly under leaves along visitor paths at five locations in the park. Male and female adults of two different Haemaphysalis species, H. shimoga and H. lagrangei, were identified. Polymerase chain reaction (PCR) analysis revealed Rickettsia bacteria in these two Haemaphysalis species; this study represents the first time such presence has been reported in Thailand. The infection rates of Rickettsia were in both H. shimoga (7.41%) and H. lagrangei (10.17%) at these locations in addition to two pools of Haemahysalis nymphs (28.57%). Furthermore, 25.93% of H. shimoga showed positive results that matched Haemaphysalis longicornis symbionts (92% sequence identity) and the Coxeilla burnetti 16S ribosomal RNA gene (90% sequence identity). We propose that this is a novel H. shimoga symbiont bacterium in Thailand and might be a novel Coxeilla-like agent or Coxeilla sp. found in H. shimoga. In contrast, we did not observe any Wolbachia bacteria, which also belong to the order Rickettsiales, in the same group of Haemaphysalis ticks. Furthermore, PCR was used to detect three other genera of bacteria, Anaplasma, Ehrlichia and Borrelia, none of which were identified in the Haemaphysalis ticks studied.  相似文献   

6.
Lyme disease risk is increasing in the United States due in part to the spread of blacklegged ticks Ixodes scapularis, the principal vector of the spirochetal pathogen Borrelia burgdorferi. A 5-year study was undertaken to investigate hypothesized coinvasion of I. scapularis and B. burgdorferi in Lower Michigan. We tracked the spatial and temporal dynamics of the tick and spirochete using mammal, bird, and vegetation drag sampling at eight field sites along coastal and inland transects originating in a zone of recent I. scapularis establishment. We document northward invasion of these ticks along Michigan’s west coast during the study period; this pattern was most evident in ticks removed from rodents. B. burgdorferi infection prevalences in I. scapularis sampled from vegetation in the invasion zone were 9.3% and 36.6% in nymphs and adults, respectively, with the majority of infection (95.1%) found at the most endemic site. There was no evidence of I. scapularis invasion along the inland transect; however, low-prevalence B. burgdorferi infection was detected in other tick species and in wildlife at inland sites, and at northern coastal sites in years before the arrival of I. scapularis. These infections suggest that cryptic B. burgdorferi transmission by other vector-competent tick species is occurring in the absence of I. scapularis. Other Borrelia spirochetes, including those that group with B. miyamotoi and B. andersonii, were present at a low prevalence within invading ticks and local wildlife. Reports of Lyme disease have increased significantly in the invasion zone in recent years. This rapid blacklegged tick invasion—measurable within 5 years—in combination with cryptic pathogen maintenance suggests a complex ecology of Lyme disease emergence in which wildlife sentinels can provide an early warning of disease emergence.  相似文献   

7.
To detect Babesia-infected Ixodes persulcatus Shulze in a suburb of St. Petersburg, Russia, 738 adult ticks were studied using Babesia specific primers and PCR techniques. The entire sample (more than 1,200 individuals) was screened for the presence of Borrelia spp., Ehrlichia spp. and tick-borne encephalitis virus (TBEV). All 7 ticks infected with Babesia microti, were also infected with other pathogens (all 7 among 417 infected ticks, zero amongst the remaining 321 naive ones (χ2 = 5.25, p < 0.05). Babesia microti occurred twice with Borrelia afzelii, 3 times with Borrelia garinii, once with both, and once with both B. garinii and TBEV. The prevalence of infection with Borrelia spp. was 34.0%, with Ehrlichia spp. 6.2%, with TBEV 1.5%, and with Ba microti 0.9%. Babesia microti infection was not found in combination with Ehrlichia sp. or Borrelia burgdorferi sensu stricto. The latter pathogen (prevalence 2.6%), just like Ba. microti, was not encountered as a monoinfection. The data suggest that Ba. microti infection can only survive in I. persulcatus in combination with Borrelia spp. (7 of 7 infections). The disease in humans is more severe and longer-lasting when more than one pathogen is involved. Our observations show that the well known St. Petersburg focus of tick-borne encephalitis and Lyme disease is also a focus of ehrlichiosis and babesiosis. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

8.
The purpose of this study was to investigate the role of wild animals for Anaplasma phagocytophilum, other ehrlichiae/anaplasmae, Rickettsia helvetica and other rickettsiae and whether different genetic variants of A. phagocytophilum in central Slovakia exist. A total of 109 spleen samples from 49 red deer (Cervus elaphus), 30 roe deer (Capreolus capreolus), 28 wild boar (Sus scrofa) and two mouflon (Ovis musimon) were collected from June 2005 to December 2006. Polymerase chain reaction (PCR) amplification of the16S rRNA gene was used for detection of ehrlichiae/anaplasmae. A nested PCR targeting part (392 bp) of groESL gene was applied for the specific detection of A. phagocytophilum. Fragments of the gltA and ompA genes (381 bp and 632 bp, respectively) were amplified to detect rickettsiae, followed by sequencing. A. phagocytophilum and R. helvetica were detected in wild animals. The prevalence of A. phagocytophilum was 50.0 ± 18.2% in roe deer and 53.1 ± 14.1% in red deer. None of the 28 wild boar was PCR positive for ehrlichiae/anaplasmae. A. phagocytophilum was detected in one mouflon. R. helvetica was found in one roe deer. Our study suggests a role of cervids as a natural reservoir of A. phagocytophilum in Slovakia. However, the role of cervids and wild boars in the circulation of R. helvetica remains unknown. The analysis of sequence variation in the msp4 coding region of A. phagocytophilum showed the presence of different variants previously described in ruminants.  相似文献   

9.
The bacterium Serratia marcescens isolated from surface-sterilised Psoroptes cuniculi was found sensitive to the antibiotic Amikacin. Mites placed in this antibiotic for 48–72 h and then washed by centrifugation were found to be alive and S. marcescens-free. Two experimental infestations were undertaken in order to verify the ability of the S. marcescens-free mites to infect and to give ear skin lesions in healthy rabbits and to evaluate the differential ability of the S. marcescens-free and S. marcescens-infected mites to give ear skin lesions. All rabbits were found to be infested, but only rabbits infested with S. marcescens-free mites presented crusts in their ears, whereas mites and/or eggs were only detected in the ear cerumen of all rabbits infested with S. marcescens-infected mites. S. marcescens was isolated only from P. cuniculi mites taken from these latter rabbits. Results indicate that P. cuniculi mites do not need S. marcescens to live and to be able to infest a healthy rabbit. In addition, S. marcescens was not isolated from eggs and newly born larvae of S. marcescens-infected P. cuniculi, demonstrating that in a population of P. cuniculi this bacterium is not transmitted transovarially.  相似文献   

10.
Sunflower (Helianthus annuus) stem canker caused by Diaporthe helianthi is one of the most important sunflower diseases in Croatia. Until recently, sunflower was the only known host for D. helianthi. In our research carried out in the area of Eastern Croatia, isolates of Diaporthe/Phomospis were collected from Xanthium italicum, X. strumarium and Arctium lappa. Using morphological, cultural and molecular ITS rDNA data, isolates from these weeds were identified as D. helianthi. The following isolates were used in the pathogenicity test: one isolate originated from sunflower (Su5/04), three from X. italicum (Xa2, Xa3 and Xa5), two from X. strumarium (Xa9 and Xa12), one from Xanthium sp. (Xa13) and one from A. lappa (Ar3). According to the results, it was determined that isolate Xa5 (originated from X. italicum) was the most pathogenic to sunflower stems. The average length of the lesion was 11.3 cm. The lowest level of pathogenicity was found in Xa9 (isolated from X. strumarium). The length of the lesion was 0.1 cm.  相似文献   

11.
Prevalence of the infectious respiratory agens, avian influenza virus (AIV), Mycobacterium avium (M. avium), and Mycobacterium avium subspecies paratuberculosis (MAP), was studied in migratory marsh-dwelling passerines captured in the Parížske močiare wetlands in Western Slovakia during 2008. Surveillance of 650 birds revealed a lower prevalence of AIV in spring (13.6%) than in summer (17.5%). A total of 14 different subtypes were detected in samples obtained from birds captured during the spring, with the most prevalent subtypes being H8N3, H6N4, H11N6 and H12N6. Subtypes H12N6, H6N6 and H2N5 were predominant in passerines captured during summer months. In eight cases, different AIV infections were detected in the oropharyngeal and cloacal samples originating from a single bird (H1N1 and H8N3; H1N3 and H9N3; H2N3 and H12N6; H2N1 and H8N1; H4N2 and H9N6; H5N5 and H11N6; H6N4 and H11N6; H7N1 and H10N3 in the oropharynx and cloaca, respectively). M. avium was detected in 9.2% and 0.8% of marsh-dwelling passerines captured during spring and summer, respectively. Only two birds were co-infected with AIV and M. avium. All birds were negative for MAP.  相似文献   

12.
Unfed adult ticks Ixodes persulcatus from five regions of Russia were examined by PCR method in order to analyze distribution and diversity of B. miyamotoi. B. miyamotoi DNA was found in 1.8, 2.9, 4.5, 2.3, and 2.5% of ticks from Leningrad, Sverdlovsk, Novosibirsk, and Irkutsk provinces, and from Khabarovsk Territory, respectively. Molecular typing of B. miyamotoi DNA was based on the partial sequencing of the 16S rRNA, p66, and glpQ genes. A single genetic variant of B. miyamotoi was detected in all the samples of ticks collected from five regions.  相似文献   

13.
Data on the geographic prevalence of Helicobacter pylori iceA and babA alleles in Eastern Europe are still relatively scant. The aim of this study was to evaluate the prevalence of iceA and babA genotypes in Bulgarian symptomatic patients. The iceA and babA genotypes were evaluated by PCR with pure cultures in strains from 196 and 181 patients, respectively. Mixed infections were found in 10.2% of all 196 patients. Prevalence of H. pylori genotypes in patients with single-strain infections was 69.3% for iceA1, 30.7% for iceA2, 82.4% for cagA +, 89.2% for vacA s1, 10.8% for vacA s2, 39.8% for vacA m1, 60.2% for vacA m2 and 48.8% for babA2. Within the iceA1 positive strains, 94.3% and 88.5% were also vacA s1a and cagA positive, respectively. Of the babA2 positive strains, 100.0%, 92.4% and 72.2% were also vacA s1a, cagA and iceA1 positive, respectively. Ulcer patients had more often strains with cagA positive status and vacA s1a allele. Although neither iceA1 nor babA2 were more common in ulcer patients, the combination of both alleles was more frequent (48.1%) in the ulcer patients than in the rest (28.7%). Clarithromycin susceptible strains had more often iceA1 allele (74.4%) than the resistant strains (55.3%). In conclusion, the results demonstrated a high prevalence of virulent H. pylori in Bulgaria. Both iceA1 and babA2 genotypes were associated with other virulence factors of H. pylori and, in addition, the iceA1 allele was associated with the strain susceptibility.  相似文献   

14.
The recent epidemic spread of the North American powdery mildew Erysiphe elevata in Europe is described and discussed. Since 2002, this plant pathogenic fungus has been collected on Catalpa bignonioides, C. erubescens and C. speciosa in the Czech Republic, Germany, Hungary, Slovakia and Switzerland. The diagnostically important anamorph of E. elevata, so far unknown, is described and illustrated in detail. Type material of Erysiphe catalpae and two specimens of E. catalpae recently collected in Poland have been examined and compared with E. elevata. The anamorph as well as the teleomorph of E. catalpae proved to be easily distinguishable from E. elevata. The supposition that E. catalpae, introduced in Armenia, was based on immature ascomata of E. elevata proved to be wrong. The origin and distribution of E. catalpae are discussed, and a key to powdery mildew fungi on Catalpa spp. in Europe is provided.  相似文献   

15.

Background  

Free-living wild rodents are often used as zoomonitors of environmental contamination. In the present study, accumulation of cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in critical organs of yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) trapped in a polluted area in Nováky, Slovakia was investigated.  相似文献   

16.
During a survey of keratinophilic fungi from soil and children’s sandpit samples in city park of Nitra and Nová Baňa (Slovakia) three noteworthy Chrysosporium species, namely Ch. europae, Ch. fluviale and Ch. minutisporosum were encountered. The species are briefly characterized here with respect to their identification, ecology and distribution. They represent newly recorded fungal taxa from Slovakia.  相似文献   

17.
The Bacteroides genus, the most prevalent anaerobic bacteria of the intestinal tract, carries a plethora of the mobile elements, such as plasmids and conjugative and mobilizable transposons, which are probably responsible for the spreading of resistance genes. Production of β-lactamases is the most important resistance mechanism including cephalosporin resistance to β-lactam agents in species of the Bacteroides fragilis group. In our previous study, the cfxA gene was detected in B. distasonis species, which encodes a clinically significant broad-spectrum β-lactamase responsible for widespread resistance to cefoxitin and other β-lactams. Such gene has been associated with the mobilizable transposon Tn4555. Therefore, the aim of this study was to detect the association between the cfxA gene and the presence of transposon Tn4555 in 53 Bacteroides strains isolated in Rio de Janeiro, Brazil, by PCR assay. The cfxA gene was detected in 11 strains and the Tn4555 in 15. The transposon sequence revealed similarities of approximately 96% with the B. vulgatus sequence which has been deposited in GenBank. Hybridization assay was performed in attempt to detect the cfxA gene in the transposon. It was possible to associate the cfxA gene in 11 of 15 strains that harbored Tn4555. Among such strains, 9 presented the cfxA gene as well as Tn4555, but in 2 strains the cfxA gene was not detected by PCR assay. Our results confirm the involvement of Tn4555 in spreading the cfxA gene in Bacteroides species.  相似文献   

18.
19.
Anaplasma phagocytophilum is transmitted mainly by hard ticks and can cause potentially fatal granulocytic anaplasmosis in humans, but its occurrence in ticks in Taiwan has never been investigated although this pathogen has been detected in Taiwanese rodents before. Ticks collected from small mammals in Hualien, eastern Taiwan, were assayed for Anaplasma infections; infections of Rickettsia and Apicomplexa protozoans were also studied. Of the 270 individually assayed Rhipicephalus haemaphysaloides ticks, A. phagocytophilum was identified in a nymphal tick. Parasites most similar to Anaplasma bovis, Rickettsia rickettsii, Rickettsia sp. TwKM01, and at least seven apicomplexan species (including genera Cryptosporidium, Hepatozoon, and Theileria) were also identified. This study shows that A. phagocytophilum does occur in the hard tick in Taiwan, although whether R. haemaphysaloides can vector this pathogen remains to be determined. This work also reveals a high diversity of tick-borne bacteria and protozoans circulating in a small region and calls for further research on their potential risks for human health.  相似文献   

20.
Tropilaelaps mercedesae is a serious ectoparasite of Apis mellifera in China. The aim of this study was to investigate the infestation rates and intensity of T. mercedesae in A. mellifera in China, and to explore the relative importance of climate, district, management practices and beekeeper characteristics that are assumed to be associated with the intensity of T. mercedesae. Of the 410 participating apiaries, 379 apiaries were included in analyses of seasonal infestation rates and 352 apiaries were included in multivariable regression analysis. The highest infestation rate (86.3%) of T. mercedesae was encountered in autumn, followed by summer (66.5%), spring (17.2%) and winter (14.8%). In autumn, 28.9% (93) of the infested apiaries were in the north (including the northeast and northwest of China), 71.1% (229) were in the central and south (including east, southeast and southwest China), and 306 apiaries (82.9%) were co-infested by both T. mercedesae and Varroa. Multivariable regression analysis showed that geographical location, season, royal jelly collection and Varroa infestation were the factors that influence the intensity of T. mercedesae. The influence of beekeeper’s education, time of beekeeping, operation size, and hive migration on the intensity of T. mercedesa was not statistically significant. This study provided information about the establishment of the linkage of the environment and the parasite and could lead to better timing and methods of control.  相似文献   

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