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Xu N, Sai L, Wang G, Dasch GA, Eremeeva ME. Utility of next-generation sequencing for the etiological diagnosis of Orientia tsutsugamushi infection. INFECTIOUS MEDICINE 2024; 3:100116. [PMID: 39220860 PMCID: PMC11362791 DOI: 10.1016/j.imj.2024.100116] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/30/2023] [Revised: 02/23/2024] [Accepted: 04/21/2024] [Indexed: 09/04/2024]
Abstract
Background Scrub typhus, an acute febrile disease caused by Orientia tsutsugamushi, is transmitted to humans through infected chigger mites. We present a case of scrub typhus in a previously healthy man from Shandong Province diagnosed using next-generation sequencing (NGS) and PCR and review recent literature on NGS for scrub typhus diagnosis. Methods NGS was utilized for testing whole blood collected on admission. Confirmatory testing was done by detecting IgM and IgG antibodies to Orientia in acute and convalescent sera by ELISA. Orientia 47-kDa protein gene TaqMan and standard PCR of the 56-kDa protein gene and Sanger sequencing were performed on eschar scab DNA. Results The NGS diagnosis was confirmed by 47-kDa protein gene TaqMan and sequencing of a fragment of the O. tsutsugamushi 56-kDa protein gene from the eschar scab. Analysis of this sequence and the NGS data indicated O. tsutsugamushi strain Cheeloo2020 is a novel genotype. Mapping of the NGS data against the O. tsutsugamushi Gilliam strain genome sequence identified 304 reads with high similarity. Conclusions NGS is not only useful for multiplex diagnosis of scrub typhus, but also provides insight into the genetic diversity of O. tsutsugamushi. The common failure to submit sequences to databases makes it difficult to determine the minimal quantity and quality of NGS data being used for the positive identification of Orientia DNA in clinical specimens.
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Affiliation(s)
- Nannan Xu
- Department of Infectious Disease of Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Lintao Sai
- Department of Infectious Disease of Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | - Gang Wang
- Department of Infectious Disease of Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan 250012, China
| | | | - Marina E. Eremeeva
- Jiann-Ping Hsu College of Public Health, Georgia Southern University, Statesboro, GA 30458, USA
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Tang C, Zhang L, Huang Y, Mai W, Xue L, Wang G, Wen S, Peng R, Wu K, Tian X, Pei H, Du J, Yuen KY, Chan JFW, Du Y, Yin F. Mixed genotypes of Orientia tsutsugamushi in conserved genes and a single immune-dominant tsa56 genotype discovered from a patient with scrub typhus in Hainan Island, China: a case report. BMC Infect Dis 2022; 22:698. [PMID: 35986264 PMCID: PMC9389790 DOI: 10.1186/s12879-022-07682-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Accepted: 08/11/2022] [Indexed: 11/10/2022] Open
Abstract
Abstract
Background
Orientia tsutsugamushi (O. tsutsugamushi), an obligate intracellular bacterium, is transmitted to humans through infected larval trombiculid mite bites, causing scrub typhus. Mixed genotypes of O. tsutsugamushi in canonical conserved genes were reported in 8–25% of blood samples from patients. Yet, there are few clinical descriptions of these mixed O. tsutsugamushi-infected patients.
Case presentation
We report a patient with scrub typhus complicated with pulmonary involvement and hepatic dysfunction, who carried mixed genotypes of the conserved genes but had a single immune-dominant 56-kDa type-specific antigen (tsa56) genotype. The patient was successfully recovered by doxycycline treatment.
Conclusions
In this reported case, both patient’s eschar and blood samples have repeatedly shown the same results, i.e., no variants were discovered in tsa56 gene that bears multiple hypervariable regions. Whereas the selected highly conserved genes were identified with up to 32 variants in a 2700 base-pair concatenated sequence. The prevalence, disease severity and mechanism of these single-tsa56-genotype mixed infections remain to be investigated on a large scale with more cases.
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Yang S, Liu X, Gao Y, Chen B, Lu L, Zheng W, Fu R, Yuan C, Liu Q, Li G, Chen H. Spatiotemporal Dynamics of Scrub Typhus in Jiangxi Province, China, from 2006 to 2018. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18094599. [PMID: 33926106 PMCID: PMC8123664 DOI: 10.3390/ijerph18094599] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/15/2021] [Accepted: 04/20/2021] [Indexed: 01/04/2023]
Abstract
Background: Scrub typhus (ST) has become a significant potential threat to public health in Jiangxi. Further investigation is essential for the control and management of the spatiotemporal patterns of the disease. Methods: Time-series analyses, spatial distribution analyses, spatial autocorrelation analysis, and space-time scan statistics were performed to detect spatiotemporal dynamics distribution of the incidence of ST. Results: From 2006 to 2018, a total of 5508 ST cases occurred in Jiangxi, covering 79 counties. The number of ST cases increased continuously from 2006 to 2018, and there was obvious seasonality during the variation process in each year, with a primary peak in autumn (September to October) and a smaller peak in summer (June to August). From 2007 to 2018, the spatial distribution of the ST epidemic was significant heterogeneity, and Nanfeng, Huichang, Xunwu, Anyuan, Longnan, and Xinfeng were hotspots. Seven spatiotemporal clusters were observed using Kulldorff's space-time scan statistic, and the most likely cluster only included one county, Nanfeng county. The high-risk areas of the disease were in the mountainous, hilly region of Wuyi and the southern mountainous region of Jiangxi. Conclusions: Targeted interventions should be executed in high-risk regions for the precise prevention and control of ST.
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Affiliation(s)
- Shu Yang
- The Collaboration Unit for Field Epidemiology of State Key Laboratory of Infectious Disease Prevention and Control, Nanchang Center for Disease Control and Prevention, Nanchang 330038, China; (S.Y.); (W.Z.); (R.F.); (C.Y.)
| | - Xiaobo Liu
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (X.L.); (Y.G.); (L.L.); (Q.L.)
| | - Yuan Gao
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (X.L.); (Y.G.); (L.L.); (Q.L.)
| | - Baizhou Chen
- School of Geography and Information Engineering, China University of Geosciences, Wuhan 430078, China;
| | - Liang Lu
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (X.L.); (Y.G.); (L.L.); (Q.L.)
| | - Weiqing Zheng
- The Collaboration Unit for Field Epidemiology of State Key Laboratory of Infectious Disease Prevention and Control, Nanchang Center for Disease Control and Prevention, Nanchang 330038, China; (S.Y.); (W.Z.); (R.F.); (C.Y.)
| | - Renlong Fu
- The Collaboration Unit for Field Epidemiology of State Key Laboratory of Infectious Disease Prevention and Control, Nanchang Center for Disease Control and Prevention, Nanchang 330038, China; (S.Y.); (W.Z.); (R.F.); (C.Y.)
| | - Chenying Yuan
- The Collaboration Unit for Field Epidemiology of State Key Laboratory of Infectious Disease Prevention and Control, Nanchang Center for Disease Control and Prevention, Nanchang 330038, China; (S.Y.); (W.Z.); (R.F.); (C.Y.)
| | - Qiyong Liu
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (X.L.); (Y.G.); (L.L.); (Q.L.)
| | - Guichang Li
- State Key Laboratory of Infectious Disease Prevention and Control, National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention, Beijing 102206, China; (X.L.); (Y.G.); (L.L.); (Q.L.)
- Correspondence: (G.L.); (H.C.)
| | - Haiying Chen
- The Collaboration Unit for Field Epidemiology of State Key Laboratory of Infectious Disease Prevention and Control, Nanchang Center for Disease Control and Prevention, Nanchang 330038, China; (S.Y.); (W.Z.); (R.F.); (C.Y.)
- Correspondence: (G.L.); (H.C.)
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Paris DH, Kelly DJ, Fuerst PA, Day NPJ, Richards AL. A Brief History of the Major Rickettsioses in the Asia-Australia-Pacific Region: A Capstone Review for the Special Issue of TMID. Trop Med Infect Dis 2020; 5:tropicalmed5040165. [PMID: 33121158 PMCID: PMC7709643 DOI: 10.3390/tropicalmed5040165] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Revised: 10/15/2020] [Accepted: 10/16/2020] [Indexed: 12/19/2022] Open
Abstract
The rickettsioses of the "Far East" or Asia-Australia-Pacific region include but are not limited to endemic typhus, scrub typhus, and more recently, tick typhus or spotted fever. These diseases embody the diversity of rickettsial disease worldwide and allow us to interconnect the various contributions to this special issue of Tropical Medicine and Infectious Disease. The impact of rickettsial diseases-particularly of scrub typhus-was substantial during the wars and "police actions" of the last 80 years. However, the post-World War II arrival of effective antibiotics reduced their impact, when recognized and adequately treated (chloramphenicol and tetracyclines). Presently, however, scrub typhus appears to be emerging and spreading into regions not previously reported. Better diagnostics, or higher population mobility, change in antimicrobial policies, even global warming, have been proposed as possible culprits of this phenomenon. Further, sporadic reports of possible antibiotic resistance have received the attention of clinicians and epidemiologists, raising interest in developing and testing novel diagnostics to facilitate medical diagnosis. We present a brief history of rickettsial diseases, their relative importance within the region, focusing on the so-called "tsutsugamushi triangle", the past and present impact of these diseases within the region, and indicate how historically, these often-confused diseases were ingeniously distinguished from each another. Moreover, we will discuss the importance of DNA-sequencing efforts for Orientia tsutsugamushi, obtained from patient blood, vector chiggers, and rodent reservoirs, particularly for the dominant 56-kD type-specific antigen gene (tsa56), and whole-genome sequences, which are increasing our knowledge of the diversity of this unique agent. We explore and discuss the potential of sequencing and other effective tools to geographically trace rickettsial disease agents, and develop control strategies to better mitigate the rickettsioses.
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Affiliation(s)
- Daniel H. Paris
- Department of Medicine, Swiss Tropical and Public Health Institute, 4051 Basel, Switzerland
- Department of Clinical Research, University of Basel, 4051 Basel, Switzerland
- Correspondence: ; Tel.: +41-61-284-8111
| | - Daryl J. Kelly
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH 43210, USA; (D.J.K.); (P.A.F.)
| | - Paul A. Fuerst
- Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH 43210, USA; (D.J.K.); (P.A.F.)
| | - Nicholas P. J. Day
- Mahidol-Oxford Tropical Medicine Research Programme, Faculty of Tropical Medicine, Mahidol University, 420/6 Rajvithee Road, Bangkok 10400, Thailand;
- Center for Tropical Medicine, Nuffield Department of Clinical Medicine, Churchill Hospital, Old Road, Headington, Oxford OX3 7LJ, UK
| | - Allen L. Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA;
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Yao H, Wang Y, Mi X, Sun Y, Liu K, Li X, Ren X, Geng M, Yang Y, Wang L, Liu W, Fang L. The scrub typhus in mainland China: spatiotemporal expansion and risk prediction underpinned by complex factors. Emerg Microbes Infect 2019; 8:909-919. [PMID: 31233387 PMCID: PMC6598543 DOI: 10.1080/22221751.2019.1631719] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
In mainland China, a geographic northward expansion of scrub typhus has been seen, highlighting the need to understand the factors and identify the risk for disease prevention. Incidence data from 1980 to 2013 were used. A Cox proportional hazard model was used to identify drivers for spatial spread, and a boosted regression tree (BRT) model was constructed to predict potential risk areas. Since the 1980s, an invasive expansion from South Natural Foci towards North Natural Foci was clearly identified, with the epidemiological heterogeneity observed between two regions, mainly in spatial distribution, seasonality, and demographic characteristics. Survival analysis disclosed significant factors contributing to the spatial expansion as following: being intersected by freeway (HR = 1.31, 95% CI: 1.11-1.54), coverage percentage of broadleaf forest (HR = 1.10, 95% CI: 1.06-1.15), and monthly average temperature (HR = 1.27, 95% CI: 1.25-1.30). The BRT models showed that precipitation, sunshine hour, temperature, crop field, and relative humidity contributed substantially to the spatial distribution of scrub typhus. A county-scale risk map was created to predict the regions with high probability of the disease. The current study enabled a comprehensive overview of epidemiological characteristics of scrub typhus in mainland China.
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Affiliation(s)
- Hongwu Yao
- a Department of Infection Management and Disease Control , Chinese PLA General Hospital , Beijing , People's Republic of China
| | - Yixing Wang
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China
| | - Xianmiao Mi
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China
| | - Ye Sun
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China.,c Center for Disease Control and Prevention of the North Military region , Jinan , People's Republic of China
| | - Kun Liu
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China.,d Department of Epidemiology and Ministry of Education Key Lab of Hazard Assessment and Control in Special Operational Environment , School of Public Health, Fourth Military Medical University , Xi'an , People's Republic of China
| | - Xinlou Li
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China.,e PLA Strategic Support Force Characteristic Medical Center , Beijing , People's Republic of China
| | - Xiang Ren
- f Division of Infectious Disease, Key Laboratory of Surveillance and Early-warning on Infectious Disease , Chinese Centre for Disease Control and Prevention , Beijing , People's Republic of China
| | - Mengjie Geng
- f Division of Infectious Disease, Key Laboratory of Surveillance and Early-warning on Infectious Disease , Chinese Centre for Disease Control and Prevention , Beijing , People's Republic of China
| | - Yang Yang
- g Department of Biostatistics , College of Public Health and Health Professions, and Emerging Pathogens Institute, University of Florida , Gainesville , FL , USA
| | - Liping Wang
- f Division of Infectious Disease, Key Laboratory of Surveillance and Early-warning on Infectious Disease , Chinese Centre for Disease Control and Prevention , Beijing , People's Republic of China
| | - Wei Liu
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China.,h Beijing Key Laboratory of Vector Borne and Natural Focus Infectious Diseases , Beijing , People's Republic of China
| | - Liqun Fang
- b The State Key Laboratory of Pathogen and Biosecurity , Beijing Institute of Microbiology and Epidemiology , Beijing , People's Republic of China
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Tilak R, Kunte R. Scrub typhus strikes back: Are we ready? Med J Armed Forces India 2019; 75:8-17. [PMID: 30705472 PMCID: PMC6349656 DOI: 10.1016/j.mjafi.2018.12.018] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2018] [Accepted: 12/31/2018] [Indexed: 01/19/2023] Open
Abstract
Scrub typhus has struck back, albeit with renewed vigour, impacting areas with previously known endemicity as also impressing newer expanses. It is not surprising, therefore, that Scrub typhus has emerged as a leading cause of public health concern globally as well as in India, but are we ready to take on the challenge? Over the last decade, there has been a global increase in the number of outbreaks of Scrub typhus, be it the military occupied areas or the civil population at large. The innumerable outbreaks of Scrub typhus, although disconcerting, have nonetheless contributed phenomenally towards better understanding of the dynamics of scrub typhus. There have been significant contributions to awareness of the disease amongst medical professionals, scrub typhus as a cause of Acute Undifferentiated Febrile Illness (AUFI) and newer clinical manifestation - Acute Encephalitis Syndrome (AES), availability and advances in diagnostics and management, man-vector-pathogen interactions, new records of Leptotrombidium species, newer vectors and Orientia species. Antigenic diversity and the varied clinical presentation of scrub typhus, absence of scrub typhus surveillance system and a lack of political will to recognize the disease as one of the important reemerging public health problem are areas seeking concerted deliberations and actions so that the challenges posed by scrub typhus can be addressed.
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Affiliation(s)
- Rina Tilak
- Scientist ‘G’, Department of Community Medicine, Armed Forces Medical College, Pune 411040, India
| | - Renuka Kunte
- Professor & Head, Department of Community Medicine, Armed Forces Medical College, Pune 411040, India
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Yoo JR, Heo ST, Kang JH, Park D, Kim JS, Bae JH, Woo JJ, Kim S, Lee KH. Mixed Infection with Severe Fever with Thrombocytopenia Syndrome Virus and Two Genotypes of Scrub Typhus in a Patient, South Korea, 2017. Am J Trop Med Hyg 2018; 99:287-290. [PMID: 29943715 DOI: 10.4269/ajtmh.18-0088] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Severe fever with thrombocytopenia syndrome (SFTS) is a tick-borne viral disease with a high mortality rate. Infection can also occur through close contact with an infected patient. Scrub typhus is an acute febrile illness caused by Orientia tsutsugamushi, a bacterium transmitted to humans through chigger mite bites. South Korea is an endemic region of SFTS and scrub typhus. In this study, we confirmed that a patient was coinfected with SFTS virus and two (Boryong and Taguchi) genotypes of O. tsutsugamushi.
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Affiliation(s)
- Jeong Rae Yoo
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Sang Taek Heo
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Ji-Hoon Kang
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Dahee Park
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Jeong Soon Kim
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Jeong Hoon Bae
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Jong Jin Woo
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Suhyun Kim
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
| | - Keun Hwa Lee
- Department of Microbiology and Immunology, Jeju National University College of Medicine, Jeju, South Korea
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Kim G, Ha NY, Min CK, Kim HI, Yen NTH, Lee KH, Oh I, Kang JS, Choi MS, Kim IS, Cho NH. Diversification of Orientia tsutsugamushi genotypes by intragenic recombination and their potential expansion in endemic areas. PLoS Negl Trop Dis 2017; 11:e0005408. [PMID: 28248956 PMCID: PMC5348041 DOI: 10.1371/journal.pntd.0005408] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 03/13/2017] [Accepted: 02/13/2017] [Indexed: 12/31/2022] Open
Abstract
Background Scrub typhus is a mite-borne febrile disease caused by O. tsutsugamushi infection. Recently, emergence of scrub typhus has attracted considerable attention in several endemic countries in Asia and the western Pacific. In addition, the antigenic diversity of the intracellular pathogen has been a serious obstacle for developing effective diagnostics and vaccine. Methodology/Principal findings To understand the evolutionary pathway of genotypic diversification of O. tsutsugamushi and the environmental factors associated with the epidemiological features of scrub typhus, we analyzed sequence data, including spatiotemporal information, of the tsa56 gene encoding a major outer membrane protein responsible for antigenic variation. A total of 324 tsa56 sequences covering more than 85% of its open reading frame were analyzed and classified into 17 genotypes based on phylogenetic relationship. Extensive sequence analysis of tsa56 genes using diverse informatics tools revealed multiple intragenic recombination events, as well as a substantially higher mutation rate than other house-keeping genes. This suggests that genetic diversification occurred via frequent point mutations and subsequent genetic recombination. Interestingly, more diverse bacterial genotypes and dominant vector species prevail in Taiwan compared to other endemic regions. Furthermore, the co-presence of identical and sub-identical clones of tsa56 gene in geographically distant areas implies potential spread of O. tsutsugamushi genotypes. Conclusions/Significance Fluctuation and diversification of vector species harboring O. tsutsugamushi in local endemic areas may facilitate genetic recombination among diverse genotypes. Therefore, careful monitoring of dominant vector species, as well as the prevalence of O. tsutsugamushi genotypes may be advisable to enable proper anticipation of epidemiological changes of scrub typhus. Scrub typhus, caused by Orientia tsutsugamushi infection, is a mite-borne febrile illness endemic in the Asia-Pacific region. Recent emergence and continuous local outbreaks in many of the endemic countries make it a serious public health issue. In addition, the antigenic diversity of the tsa56 gene, encoding a major outer membrane protein, hampers the development of effective diagnostics and vaccine. Here, we extensively analyzed tsa56 sequences and their spatiotemporal information to elucidate the evolutionary pathway of genotypic diversification, as well as the environmental basis associated with the epidemiological changes of scrub typhus. Based on various informatics analyses, we found that genetic diversification of tsa56 might have been attained via frequent point mutations and subsequent genetic recombination among diverse genotypes. Prevalence of numerous bacterial genotypes and dominant vector species in Taiwan also suggest that the subtropical area located at the center of endemicity, may serve as a local mixing ground for genotype diversification. In addition, detection of identical and sub-identical clones of tsa56 genes in geographically distant countries indicates a potential spreading of bacterial genotypes. Continuous monitoring of dominant vector species and the associated O. tsutsugamushi genotypes might be required for developing better diagnostics and an effective vaccine for scrub typhus.
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Affiliation(s)
- Gwanghun Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Na-Young Ha
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Chan-Ki Min
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hong-Il Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Nguyen Thi Hai Yen
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Keun-Hwa Lee
- Department of Microbiology and Immunology, Jeju National University School of Medicine, Jeju, Republic of Korea
| | - Inbo Oh
- Environmental Health Center, University of Ulsan College of Medicine, Ulsan, Republic of Korea
| | - Jae-Seung Kang
- Department of Microbiology, Inha University School of Medicine, Incheon, Republic of Korea
| | - Myung-Sik Choi
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Ik-Sang Kim
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Nam-Hyuk Cho
- Department of Microbiology and Immunology, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University College of Medicine, Seoul, Republic of Korea
- Institute of Endemic Disease, Seoul National University Medical Research Center and Bundang Hospital, Seoul, Republic of Korea
- * E-mail:
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