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Emerging Infectious Diseases May 2019PCR amplification indicated the minimum infection rate of Rickettsia spp. was 0.66% in Haemaphysalis longicornis ticks collected from Shandong Province, China....
PCR amplification indicated the minimum infection rate of Rickettsia spp. was 0.66% in Haemaphysalis longicornis ticks collected from Shandong Province, China. Phylogenetic analysis based on the rrs, gltA, ompA, and ompB genes indicated that the ticks carried R. japonica, Candidatus Rickettsia longicornii, and a novel Rickettsia species related to R. canadensis.
Topics: Animals; China; DNA, Bacterial; Humans; Phylogeny; Polymerase Chain Reaction; Public Health Surveillance; Rickettsia; Ticks; Vector Borne Diseases
PubMed: 31002060
DOI: 10.3201/eid2505.171745 -
Infectious Disease Reports Dec 2020(1) Background. () infection induces severe inflammation, and the disappearance of eosinophil in the acute stage is one of the phenomena. (2) Materials and Methods. In...
(1) Background. () infection induces severe inflammation, and the disappearance of eosinophil in the acute stage is one of the phenomena. (2) Materials and Methods. In the current study, we measured the serum concentrations of Th1, Th2, and Th17 cytokines in the acute and recovery stages. (3) Results. In the acute phase, IL-6 and IFN-γ levels were elevated and we speculated that they played a role as a defense mechanism against . The high concentration of IFN-γ suppressed the differentiation of eosinophil and induced apoptosis of eosinophil, leading to the disappearance of eosinophil. On day 7, IL-6 and IFN-γ concentrations were decreased, and Th2 cytokines such as IL-5 and IL-9 were slightly increased. On day 14, eosinophil count recovered to the normal level. The transition of serum cytokine concentration in infection was presented. (4) Conclusions. IL-6 and IFN-γ seem to be critical cytokines as defense mechanism against in the acute phase, and this may deeply connect to the decrease of eosinophil.
PubMed: 33322277
DOI: 10.3390/idr12030023 -
Emerging Infectious Diseases Sep 2019During 2014-2017, we screened for Rickettsia japonica infection in Xinyang, China, and identified 20 cases. The major clinical manifestations of monoinfection were...
During 2014-2017, we screened for Rickettsia japonica infection in Xinyang, China, and identified 20 cases. The major clinical manifestations of monoinfection were fever, asthenia, myalgia, rash, and anorexia; laboratory findings included thrombocytopenia and elevated hepatic aminotransferase concentrations. Physicians in China should consider R. japonica infection in at-risk patients.
Topics: Adult; Aged; Animals; China; Female; Humans; Male; Middle Aged; Phylogeny; Rickettsia; Rickettsia Infections; Risk Factors; Tick Bites; Ticks
PubMed: 31441748
DOI: 10.3201/eid2509.171421 -
Frontiers in Microbiology 2019is the causative agent of Far-Eastern spotted fever (FESF). In Japan, a human case of FESF was identified in Sendai in Miyagi Prefecture in 2008, and bacteria were...
is the causative agent of Far-Eastern spotted fever (FESF). In Japan, a human case of FESF was identified in Sendai in Miyagi Prefecture in 2008, and bacteria were isolated from ticks collected in the suspected geographical area of infection. Although the intraspecies genome diversity of Rickettsia has been poorly investigated, our recent analysis revealed extremely low genomic diversity of , the agent of Japanese spotted fever, which is a close relative of . In this study, to investigate the genomic diversity of and understand the genetic relationship between Japanese and Chinese isolates, we sequenced three isolates from ticks collected in Sendai and one isolate from a tick collected in Inner Mongolia, China, and performed genomic comparisons between these isolates and strain 054, the type strain isolated from a tick in Heilongjiang Province, China. Although the three Japanese strains were isolated in 2008, 2009, and 2012, their genome sequences were identical, indicating that ticks carrying a single clone have been distributed in Sendai, Japan. Among the five isolates, only 81 SNPs and 13 insertion/deletion sites were identified, despite the significant differences in these isolates both geographically and temporally. A significant portion of the 81 SNPs (16/81) were found to be recombinogenic. These results indicate low genomic diversity of , as observed in . We further performed a detailed genomic comparison of and to accurately define conserved and species-specific genes. This analysis revealed that although notable variations were found in the genomic loci encoding RelA/SpoT family proteins and tandem repeats in major surface proteins, there was only a small difference in the gene repertoire between the two species, suggesting that SNPs and small InDels are responsible for the functional or physiological differences between the two species, if present. Through this analysis, several species-specific genomic regions that can serve as ideal PCR targets for distinguishing and were also identified.
PubMed: 31866968
DOI: 10.3389/fmicb.2019.02787 -
Microbiology Spectrum Oct 2022The increasing awareness of emerging tickborne pathogens (TBPs) has inspired much research. In the present study, the coinfections of TBPs both in ticks and their wild...
The increasing awareness of emerging tickborne pathogens (TBPs) has inspired much research. In the present study, the coinfections of TBPs both in ticks and their wild hedgehog hosts in Jiangsu province, Eastern China were determined by metagenome next-generation sequencing and nested PCR. As a result, Rickettsia japonica (81.1%), novel sp. SFGR-1 (5.1%), Anaplasma bovis (12%), A. platys (6.3%), novel spp. Ehr-1 (16%) and Ehr-2 (0.6%), E. ewingii-like strain (0.6%), Coxiella burnetii (10.9%), and a novel -like endosymbiont (CLE) strain (61.1%) were detected in ticks. A. bovis (43.8%), sp. Ehr-1 (83.3%), and C. burnetii (80%) were detected in Erinaceus amurensis hedgehogs. Coinfection rates with various TBPs were 71.5% and 83.3% in ticks and hedgehogs, respectively, both with double-pathogen/endosymbiont coinfection rates over 50%. We found the following. (i) hedgehogs seem to contribute to the natural cycles of , , sp., and C. burnetii and may be reservoirs of them except for , and is proved to infect hedgehogs for the first time. (ii) is proved to harbor various TBPs as a reservoir host, including CLE identified for the first time, which could inhibit coinfection of C. burnetii while promoting that of spp. in (iii) Four novel TBP species were identified. This study provides useful epidemiological information crucial for assessing the potential infection risks to humans, thus benefiting the development of strategies to prevent and control tick-borne diseases. In the present study, we found the following. (i) hedgehogs seem to contribute to the natural cycles of , , sp., and C. burnetii and may be reservoirs of them except for , and is proved to infect hedgehogs for the first time. (ii) is proved to harbor various tickborne pathogens (TBPs) as a reservoir host, including -like endosymbiont (CLE) identified for the first time, which could inhibit coinfection of C. burnetii while promoting that of spp. in (iii) Four novel TBP species were identified. This study provides useful epidemiological information on TBPs harbored and transmitted by ticks and their hosts, for assessing the potential infection risks to humans, thus benefiting the developing strategies for tick-borne diseases prevention and control.
Topics: Animals; Humans; Ticks; Hedgehogs; Coinfection; Rickettsia; Tick-Borne Diseases; Ehrlichia; Parasites
PubMed: 36000911
DOI: 10.1128/spectrum.02138-22 -
PloS One 2024Ixodid ticks, such as Ixodes ovatus and Haemaphysalis flava, are important vectors of tick-borne diseases in Japan, such as Japanese spotted fever caused by Rickettsia...
Ixodid ticks, such as Ixodes ovatus and Haemaphysalis flava, are important vectors of tick-borne diseases in Japan, such as Japanese spotted fever caused by Rickettsia japonica. This study describes the Rickettsia infection rates influenced by the population genetic structure of I.ovatus and H. flava along an altitudinal gradient. A total of 346 adult I. ovatus and 243 H. flava were analyzed for the presence of Rickettsia by nested PCR targeting the 17kDA, gltA, rOmpA, and rOmpB genes. The population genetic structure was analyzed utilizing the mitochondrial cytochrome oxidase 1 (cox1) marker. The Rickettsia infection rates were 13.26% in I. ovatus and 6.17% in H. flava. For I. ovatus, the global FST value revealed significant genetic differentiation among the different populations, whereas H. flava showed non-significant genetic differentiation. The cox1 I. ovatus cluster dendrogram showed two cluster groups, while the haplotype network and phylogenetic tree showed three genetic groups. A significant difference was observed in Rickettsia infection rates and mean altitude per group between the two cluster groups and the three genetic groups identified within I. ovatus. No significant differences were found in the mean altitude or Rickettsia infection rates of H. flava. Our results suggest a potential correlation between the low gene flow in I. ovatus populations and the spatially heterogeneous Rickettsia infection rates observed along the altitudinal gradient. This information can be used in understanding the relationship between the tick vector, its pathogen, and environmental factors, such as altitude, and for the control of tick-borne diseases in Japan.
Topics: Animals; Ixodes; Altitude; Phylogeny; Ixodidae; Rickettsia Infections; Rickettsia; Spotted Fever Group Rickettsiosis; Genetic Structures
PubMed: 38478554
DOI: 10.1371/journal.pone.0298656 -
Clinics and Practice Feb 2023and spp. are pathogens transmitted by ticks to humans. However, the developmental stage of the tick carrying the greatest risk of infection is unknown. Detection of...
and spp. are pathogens transmitted by ticks to humans. However, the developmental stage of the tick carrying the greatest risk of infection is unknown. Detection of pathogen-specific genes proves that ticks carrying or spp. constitute a reservoir of infection. However, conventional PCR methods are unable to quantitate the pathogens within ticks. In the present study, we collected ticks in the endemic area of Japanese spotted fever, caused by , and determined the rate of tick-borne pathogens carried by the ticks. As a method of evaluation, next-generation sequencing was used to estimate the proportion of pathogens in 10 adult and 10 larval ticks. Ticks were identified (H.L) from the results of the sequencing of PCR products amplified using tick identification-specific primers. The gene detection rates were 10/10 for sp. and 10/10 for sp. among the adult ticks. For the larval ticks, the ratios were 7/10 and 5/10 for sp. and sp., respectively. The largest proportion of sp.-specific DNA reached 96% in one adult tick. The proportion of sp. genes ranged from 1.76% to 41.81% (mean, 15.56%) in the adult ticks. The proportions of and spp. genes in the larvae ranged from 0% to 27.4% (mean 5.86%) and from 0% to 14.6% (mean 3.38%), respectively. When the percentage of sp., out of all pathogens detected via next-generation sequencing, was analyzed between the adult and larval stages of the ticks, a significant difference was observed at = 0.0254. For sp., a highly significant difference ( < 0.0001) was found between the adult and larval stages of the ticks. In conclusion, the detection rates and proportions of and spp. genes were highest in adult H.L ticks. The risk of contracting tick-borne infections may increase with bites from adult ticks, especially those harboring sp.
PubMed: 36826164
DOI: 10.3390/clinpract13010022 -
Tropical Medicine and Infectious Disease Dec 2022Ticks can carry and transmit a large number of pathogens, including bacteria, viruses and protozoa, posing a huge threat to human health and animal husbandry. Previous...
Ticks can carry and transmit a large number of pathogens, including bacteria, viruses and protozoa, posing a huge threat to human health and animal husbandry. Previous investigations have shown that the dominant species of ticks in Shanghai are and . However, no relevant investigations and research have been carried out in recent decades. Therefore, we investigated the bacterial communities and tick-borne pathogens (TBPs) in spp. from Shanghai, China. Ixodid ticks were collected from 18 sites in Shanghai, China, and identified using morphological and molecular methods. The V3-V4 hypervariable regions of the bacterial 16S rRNA gene were amplified from the pooled tick DNA samples and subject to metagenomic analysis. The microbial diversity in the tick samples was estimated using the alpha diversity that includes the observed species index and Shannon index. The Unifrac distance matrix as determined using the QIIME software was used for unweighted Unifrac Principal coordinates analysis (PCoA). Individual tick DNA samples were screened with genus-specific or group-specific nested polymerase chain reaction (PCR) for these TBPs and combined with a sequencing assay to confirm the results of the V3-V4 hypervariable regions of the bacterial 16S rRNA gene. We found and to be the dominant species of ticks in Shanghai in this study. Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria are the main bacterial communities of spp. The total species abundances of Proteobacteria, Firmicutes and Bacteroidetes, are 48.8%, 20.8% and 18.1%, respectively. At the level of genus analysis, and carried at least 946 genera of bacteria. The bacteria with high abundance include , , and . Additionally, , , , , , , spp. and -like endosymbiont were detected in spp. from Shanghai, China. This study is the first report of bacterial communities and the prevalence of some main pathogens in spp. from Shanghai, China, and may provide insights and evidence for bacterial communities and the prevalence of the main pathogen in ticks. This study also indicates that people and other animals in Shanghai, China, are exposed to several TBPs.
PubMed: 36548668
DOI: 10.3390/tropicalmed7120413 -
Clinical and Vaccine Immunology : CVI Jan 2011Rickettsia japonica pathogenesis and reservoir potential in dogs were evaluated by both experimental inoculation and epidemiologic survey. In the experimental...
Rickettsia japonica pathogenesis and reservoir potential in dogs were evaluated by both experimental inoculation and epidemiologic survey. In the experimental inoculation study, dogs 1 and 2 were pretreated with an immunosuppressive dose of cyclosporine 14 days before inoculation and became ill after exposure to R. japonica. Dogs exhibited clinical signs, including fever, anorexia, depression, and decreased water consumption, between 36 and 96 h after inoculation, but these signs disappeared spontaneously by 5 days after inoculation. Dogs 3 and 4 were not pretreated with cyclosporine, and no clinical signs were detected in them throughout the 14-day observation period. The control dog was clinically normal and had a normal rectal temperature throughout the study period. We attempted to detect rickettsial DNA from peripheral blood and aspiration samples from kidney and spleen by nested PCR, but all samples examined were negative. The control dog lacked detectable titers to R. japonica antigen on day 14, while positive antibodies to R. japonica were detected in all four experimentally infected dogs, with titers of 1:160 to 1:80. In the epidemiologic survey, 24 (1.8%) of the 1,363 dogs examined throughout Japan had antibodies against R. japonica, with titers of 1:40 or more. However, we observed neither clinical signs at the time of sample collection nor nested PCR results indicative of rickettsial infection in these dogs. In conclusion, dogs in Japan can be exposed to R. japonica, and infected dogs with immunosuppressive conditions can temporarily develop clinical symptoms, including fever, anorexia, depression, and decreased water consumption.
Topics: Animals; Antibodies, Bacterial; DNA, Bacterial; Disease Reservoirs; Dog Diseases; Dogs; Japan; Rickettsia; Rickettsia Infections
PubMed: 20980481
DOI: 10.1128/CVI.00369-10 -
IDCases 2021Two patients from Huanggang, China, were diagnosed with spotted fever group (SFG) rickettsiosis-caused by ()-in 2021. This study aimed to investigate the clinical...
Two patients from Huanggang, China, were diagnosed with spotted fever group (SFG) rickettsiosis-caused by ()-in 2021. This study aimed to investigate the clinical symptoms, laboratory examinations, epidemiological factors, and therapeutic responses in patients with SFG rickettsiosis-an emerging disease in this region. The patients showed a variety of clinical signs and symptoms, such as acute febrile illness with severe headache, myalgia, asthenia, anorexia, eschar, lymphadenopathy, and rash on the trunk and extremities. They exhibited increased neutrophil ratio, mild thrombocytopenia, liver dysfunction, and increased C-reactive protein and procalcitonin levels. Following treatment with doxycycline, the patients recovered completely. This is the first report of infection in Huanggang City, Hubei Province, China. infection is a tick-borne disease, which can be effectively treated with doxycycline; however, it has a mortality rate of approximately 10% with delays in treatment. The Huanggang area is also a high-risk area for tick-borne severe fever with thrombocytopenia syndrome (SFTS). Therefore, SFTS and SFG rickettsiosis should be carefully diagnosed in this area and clinicians should be alert with respect to the possibility of infections with both SFTS and SFG rickettsiosis.
PubMed: 34712573
DOI: 10.1016/j.idcr.2021.e01309