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Fujisawa N, Fujita H, Fujita N, Sakai T, Kawase J, Ando S, Tabara K. Transmission Cycle of Shimokoshi-Type Orientia tsutsugamushi in Shimane Prefecture, Japan. Jpn J Infect Dis 2024; 77:55-58. [PMID: 37648489 DOI: 10.7883/yoken.jjid.2023.137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/01/2023]
Abstract
To demonstrate the transmission cycle of Shimokoshi-type Orientia tsutsugamushi in Shimane Prefecture, field rodents were captured from areas where four human infections caused by the pathogen have been reported. The rodents were investigated for the transmission cycle of the pathogen based on the pathogen's genome, antibodies against the pathogen, and the vector of the pathogen (Leptotrombidium palpale). In addition, the vector was captured from the soil in the study area. A total of 44 rodents were captured. No O. tsutsugamushi DNA was detected in the blood or spleen samples by real-time polymerase chain reaction. However, a specific antibody against the pathogen was detected in 2 out of 44 (4.5%) rodents using the indirect immunoperoxidase method, indicating the presence of the pathogen in the study area. Although 29 L. palpale were identified, DNA detection was not performed because of the insufficient number of vectors, based on the DNA detection rate in previous studies. However, the identification of the vector, as well as the specific antibody in rodents, suggests the presence of the transmission cycle of Shimokoshi-type O. tsutsugamushi in Shimane Prefecture.
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Affiliation(s)
- Naoki Fujisawa
- Division of Virology, Shimane Prefectural Institute of Public Health and Environmental Science, Japan
| | - Hiromi Fujita
- Mahara Institute of Medical Acarology, Japan
- Institute of Rickettsioses, Kita-Fukushima Medical Center, Japan
| | - Nobuko Fujita
- Mahara Institute of Medical Acarology, Japan
- Institute of Rickettsioses, Kita-Fukushima Medical Center, Japan
| | - Tomotake Sakai
- Shimane Prefectural Institute of Hamada Public Health Center, Japan
| | - Jun Kawase
- Division of Bacteriology, Shimane Prefectural Institute of Public Health and Environmental Science, Japan
| | - Shuji Ando
- Department of Virology I, National Institute of Infectious Diseases, Japan
| | - Kenji Tabara
- Department of Health and Welfare, Shimane Prefectural Governmental Office, Japan
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Ogawa M, Takada N, Noda S, Takahashi M, Matsutani M, Kageyama D, Ebihara H. GENETIC VARIATION OF LEPTOTROMBIDIUM (ACARI: TROMBICULIDAE) MITES CARRYING ORIENTIA TSUTSUGAMUSHI, THE BACTERIAL PATHOGEN CAUSING SCRUB TYPHUS. J Parasitol 2023; 109:340-348. [PMID: 37498779 PMCID: PMC10658875 DOI: 10.1645/22-97] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/29/2023] Open
Abstract
Leptotrombidium (Acari: Trombiculidae) mites are carriers of Orientia tsutsugamushi, the bacterial pathogen causing scrub typhus in humans. Classification of Leptotrombidium is vital because limited mite species carry O. tsutsugamushi. Generally, Leptotrombidium at the larval stage (approximately 0.2 mm in size) are used for morphological identification. However, morphological identification is often challenging because it requires considerable skills and taxonomic expertise. In this study, we found that the full-length sequences of the mitochondrial cytochrome c oxidase subunit 1 gene varied among the significant Leptotrombidium. On the basis of these, we modified the canonical deoxyribonucleic acid (DNA) barcoding method for animals by redesigning the primer set to be suitable for Leptotrombidium. Polymerase chain reaction with the redesigned primer set drastically increased the detection sensitivity, especially against Leptotrombidium scutellare (approximately 17% increase), one of the significant mites carrying O. tsutsugamushi. Phylogenetic analysis showed that the samples morphologically classified as L. scutellare and Leptotrombidium pallidum were further split into 3 and 2 distinct subclusters respectively. The mean genetic distance (p-distance) between L. scutellare and L. pallidum was 0.2147, whereas the mean distances within each species were 0.052 and 0.044, respectively. Within L. scutellare, the mean genetic distances between the 3 subclusters were 0.1626-0.1732, whereas the distances within each subcluster were 0.003-0.017. Within L. pallidum, the mean genetic distance between the 2 subclusters was 0.1029, whereas the distances within each subcluster were 0.010-0.013. The DNA barcoding uncovered a broad genetic diversity of Leptotrombidium, especially of L. scutellare and L. pallidum, the notable species carrying O. tsutsugamushi. We conclude that the DNA barcoding using our primers enables precise and detailed classification of Leptotrombidium and implies the existence of a subgenotype in Leptotrombidium that had not been found by morphological identification.
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Affiliation(s)
- Motohiko Ogawa
- Department of Virology I, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
| | - Nobuhiro Takada
- Faculty of Medical Sciences, University of Fukui, 23-3 Matsuoka, Eiheiji, Fukui 910-1193, Japan
| | - Shinichi Noda
- Research Center for the Pacific Islands, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-8580, Japan
| | - Mamoru Takahashi
- Department of Anesthesiology, Saitama Medical University, 38 Moroyama-Machi, Iruma-Gun, Saitama, 350-0495, Japan
| | - Minenosuke Matsutani
- NODAI Genome Research Center, Tokyo University of Agriculture, 1-1-1 Sakuragaoka, Setagaya, Tokyo 156-8502, Japan
| | - Daisuke Kageyama
- Institute of Agrobiological Sciences, National Agriculture and Food Research Organization, 1-2, Owashi, Tsukuba, Ibaraki 305-0851, Japan
| | - Hideki Ebihara
- Department of Virology I, National Institute of Infectious Diseases, 1-23-1, Toyama, Shinjuku-ku, Tokyo 162-8640, Japan
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Moniuszko H, Wojnarowski K, Cholewińska P. Not Only Leptotrombidium spp. an Annotated Checklist of Chigger Mites (Actinotrichida: Trombiculidae) Associated with Bacterial Pathogens. Pathogens 2022; 11:pathogens11101084. [PMID: 36297141 PMCID: PMC9611227 DOI: 10.3390/pathogens11101084] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/19/2022] [Accepted: 09/20/2022] [Indexed: 12/02/2022] Open
Abstract
Mites of the family Trombiculidae are known for playing a role in maintaining and spreading the scrub typhus etiologic agent, an intracellular Gram-negative bacterium, Orientia tsutsugamushi. Species of the genus Leptotrombidium are investigated most thoroughly, particularly in SE Asia, and a few are proven vectors for the pathogen. The mentioned association, however, is not the only one among trombiculids. Here, we present a list of chiggers indicated in the literature as positive for bacterial pathogens, tested throughout almost 100 years of research. Taxonomic identities of trombiculids follow recent revisions and checklists. Results point at 100 species, from 28 genera, evidenced for association with 31 bacterial taxa. Pathogen-positive mites constitute around 3.3% of the total number of species comprising the family. Discussed arachnids inhabit six biogeographic realms and represent free-living instars as well as external and internal parasites of rodents, soricomorphs, scadents, lagomorphs, peramelemorphs, bats, passerine birds, reptiles and humans. A variety of so far detected bacteria, including novel species, along with the mites’ vast geographical distribution and parasitism on differentiated hosts, indicate that revealing of more cases of Trombiculidae-pathogens association is highly probable, especially utilizing the newest techniques enabling a large-scale bacterial communities survey.
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Affiliation(s)
- Hanna Moniuszko
- Section of Basic Research in Horticulture, Department of Plant Protection, Institute of Horticultural Sciences, Warsaw University of Life Sciences—SGGW, 02-776 Warsaw, Poland
- Correspondence:
| | - Konrad Wojnarowski
- Chair for Fish Diseases and Fisheries Biology, Ludwig-Maximilians-University of Munich, 80539 Munich, Germany
| | - Paulina Cholewińska
- Institute of Animal Breeding, Wroclaw University of Environmental and Life Sciences, 51-630 Wroclaw, Poland
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Kinoshita H, Arima Y, Shigematsu M, Sunagawa T, Saijo M, Oishi K, Ando S. Descriptive epidemiology of rickettsial infections in Japan: Scrub typhus and Japanese spotted fever, 2007-2016. Int J Infect Dis 2021; 105:560-566. [PMID: 33610785 DOI: 10.1016/j.ijid.2021.02.069] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 11/30/2022] Open
Abstract
OBJECTIVE This study aimed to describe the epidemiological and clinical characteristics of endemics of two rickettsial diseases, scrub typhus (ST) and Japanese spotted fever (JSF), in Japan. METHODS We conducted a retrospective, descriptive epidemiological assessment of cases notified via national surveillance from 2007-2016. RESULTS Over the 10-year period, 4185 ST and 1765 JSF cases were notified; of these, 20 (0.48%) cases of ST and 16 (0.91%) cases of JSF were fatal at the time of reporting. The elderly had higher notification rates and fatalities. While the annual number of ST notifications was stable and cases were reported from a broad geographic range, the number of JSF reports increased three-fold, expanding from the southwest to the east. The seasonality of ST varied by region and was more common during spring/summer in the north and autumn/winter in the south; 78% of cases occurred during autumn/winter, mainly in the southern region. Most of the fatal ST cases occurred in the spring/summer and occurred in the northern region. CONCLUSION Our analysis identified seasonal and regional variations in the distribution of rickettsiosis. These variations were most likely to be related to the ecology of the vectors and etiological agents. Knowing the recent epidemiological and clinical features of ST and JSF can support clinical diagnosis and guide preventative activities against these vector-borne diseases.
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Affiliation(s)
| | - Yuzo Arima
- National Institute of Infectious Diseases, Tokyo, Japan
| | | | | | | | | | - Shuji Ando
- National Institute of Infectious Diseases, Tokyo, Japan.
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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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Kikuchi H, Narita M, Chida Y, Ishida T, Shinohara K. Case Report: A Fatal Case of Scrub Typhus Complicated by Heatstroke. Am J Trop Med Hyg 2020; 103:2469-2471. [PMID: 32975175 DOI: 10.4269/ajtmh.20-0577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A 76-year-old man who had been bathing in a hot spring was taken to the hospital in a coma. PCR assay performed on the eschar revealed a serotype Hirano/Kuroki of Orientia tsutsugamushi. Coexisted heatstroke superimposed on multiple underlying risk factors likely led to a fatal clinical course.
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Affiliation(s)
- Hiroaki Kikuchi
- Department of Emergency and Critical Care Medicine, Ohta Nishinouchi Hospital, Koriyama, Japan
| | - Masashi Narita
- Division of Infectious Diseases, Department of Medicine, Okinawa Chubu Hospital, Uruma, Japan
| | - Yasuyuki Chida
- Department of Emergency and Critical Care Medicine, Ohta Nishinouchi Hospital, Koriyama, Japan
| | - Tokiya Ishida
- Department of Emergency and Critical Care Medicine, Ohta Nishinouchi Hospital, Koriyama, Japan
| | - Kazuaki Shinohara
- Department of Emergency and Critical Care Medicine, Ohta Nishinouchi Hospital, Koriyama, Japan
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Kim SY, Gill B, Song BG, Chu H, Park WI, Lee HI, Shin EH, Cho SH, Roh JY. Annual Fluctuation in Chigger Mite Populations and Orientia Tsutsugamushi Infections in Scrub Typhus Endemic Regions of South Korea. Osong Public Health Res Perspect 2019; 10:351-358. [PMID: 31897364 PMCID: PMC6927423 DOI: 10.24171/j.phrp.2019.10.6.05] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Objectives Chigger mites are vectors for scrub typhus. This study evaluated the annual fluctuations in chigger mite populations and Orientia tsutsugamushi infections in South Korea. Methods During 2006 and 2007, chigger mites were collected monthly from wild rodents in 4 scrub typhus endemic regions of South Korea. The chigger mites were classified based on morphological characteristics, and analyzed using nested PCR for the detection of Orientia tsutsugamushi. Results During the surveillance period, the overall trapping rate for wild rodents was 10.8%. In total, 17,457 chigger mites (representing 5 genera and 15 species) were collected, and the average chigger index (representing the number of chigger mites per rodent), was 31.7. The monthly chigger index was consistently high (> 30) in Spring (March to April) and Autumn (October to November). The mite species included Leptotrombidium pallidum (43.5%), L. orientale (18.9%), L. scutellare (18.1%), L. palpale (10.6%), and L. zetum (3.6%). L. scutellare and L. palpale populations, were relatively higher in Autumn. Monthly O. tsutsugamushi infection rates in wild rodents (average: 4.8%) and chigger mites (average: 0.7%) peaked in Spring and Autumn. Conclusion The findings demonstrated a bimodal pattern of the incidence of O. tsutsugamushi infections. Higher infection rates were observed in both wild rodents and chigger mites, in Spring and Autumn. However, this did not reflect the unimodal incidence of scrub typhus in Autumn. Further studies are needed to identify factors, such as human behavior and harvesting in Autumn that may explain this discordance.
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Affiliation(s)
- Seong Yoon Kim
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Byoungchul Gill
- Division of Laboratory Diagnosis Management, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Bong Gu Song
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Hyuk Chu
- Division of Bacterial Disease Research, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Won Il Park
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Hee Il Lee
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - E-Hyun Shin
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Shin-Hyeong Cho
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
| | - Jong Yul Roh
- Division of Vectors and Parasitic Diseases, Korea Centers for Disease Control and Prevention, Cheongju, Korea
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Sato K, Takano A, Gaowa, Ando S, Kawabata H. Epidemics of tick-borne infectious diseases in Japan. ACTA ACUST UNITED AC 2019. [DOI: 10.7601/mez.70.3] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Kozue Sato
- National Institute of Infectious Diseases
| | - Ai Takano
- Joint Faculty of Veterinary Medicine, Yamaguchi University
| | - Gaowa
- Department of Medicine, Hetao College
| | - Shuji Ando
- National Institute of Infectious Diseases
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Kawamori F, Shimazu Y, Sato H, Monma N, Ikegaya A, Yamamoto S, Fujita H, Morita H, Tamaki Y, Takamoto N, Su H, Shimada M, Shimamura Y, Masuda S, Ando S, Ohashi N. Evaluation of Diagnostic Assay for Rickettsioses Using Duplex Real-Time PCR in Multiple Laboratories in Japan. Jpn J Infect Dis 2018; 71:267-273. [PMID: 29709963 DOI: 10.7883/yoken.jjid.2017.447] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Tsutsugamushi disease and Japanese spotted fever are representative rickettsioses in Japan, and are caused by infection with Orientia tsutsugamushi and Rickettsia japonica, respectively. For molecular-based diagnosis, conventional PCR assays, which independently amplify respective rickettsial DNA, are usually used; however, this approach is time-consuming. Here, we describe a new duplex real-time PCR assay for the simultaneous detection of O. tsutsugamushi and spotted fever group rickettsiae, and its evaluation using several PCR conditions in 6 public health laboratories. The detection limit of the assay was estimated to be 102 copies and the sensitivity was almost identical to that of 3 conventional PCR methods. A total of 317 febrile patients were selected as clinically suspected or confirmed cases of rickettsioses. The detection efficiency of this assay for O. tsutsugamushi from blood or skin (eschar) specimens appeared to be almost the same as that of the conventional PCR method, even when performed in different laboratories, whereas the efficiency for spotted fever group rickettsiae tended to be higher than that of the 2 traditional double PCR assays. Our duplex real-time PCR is thus a powerful tool for the rapid diagnosis of rickettsioses, especially at the acute stage of infection.
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Affiliation(s)
- Fumihiko Kawamori
- Shizuoka Institute of Environment and Hygiene.,Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Yukie Shimazu
- Hiroshima Prefectural Technology Research Institute, Public Health and Environment Center
| | - Hiroko Sato
- Akita Research Center for Public Health and Environment
| | | | | | - Seigo Yamamoto
- Miyazaki Prefectural Institute for Public Health and Environment
| | | | | | | | - Naoya Takamoto
- Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Hongru Su
- Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Masahiko Shimada
- Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Yuko Shimamura
- Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Shuichi Masuda
- Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
| | - Shuji Ando
- Department of Virology I, National Institute of Infectious Diseases
| | - Norio Ohashi
- Department of Food and Nutritional Sciences, Graduate School of Integrated Pharmaceutical and Nutritional Sciences, University of Shizuoka
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Meteorological factors affecting scrub typhus occurrence: a retrospective study of Yamagata Prefecture, Japan, 1984–2014. Epidemiol Infect 2016; 145:462-470. [DOI: 10.1017/s0950268816002430] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
SUMMARYClimate change, by its influence on the ecology of vectors might affect the occurrence of vector-borne diseases. This study examines the effects of meteorological factors in Japan on the occurrence of scrub typhus, a mite-borne zoonosis caused byOrientia tsutsugamushi. Using negative binomial regression, we analysed the relationships between meteorological factors (including temperature, rainfall, snowfall) and spring–early summer cases of scrub typhus in Yamagata Prefecture, Japan, during 1984–2014. The average temperature in July and August of the previous year, cumulative rainfall in September of the previous year, snowfall throughout the winter, and maximum depth of snow cover in January and February were positively correlated with the number of scrub typhus cases. By contrast, cumulative rainfall in July of the previous year showed a negative relationship to the number of cases. These associations can be explained by the life-cycle ofLeptotrombidium pallidum, a predominant vector of spring–early summer cases of scrub typhus in northern Japan. Our findings show that several meteorological factors are useful to estimate the number of scrub typhus cases before the endemic period. They are applicable to establish an early warning system for scrub typhus in northern Japan.
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11
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Suzuki Y, Shimanuki M, Seto J, Yahagi K, Mizuta K. A Case of Scrub Typhus Imported from South Korea to Yamagata, Japan. Jpn J Infect Dis 2016; 69:454-6. [PMID: 27357993 DOI: 10.7883/yoken.jjid.2016.121] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- Yu Suzuki
- Department of Microbiology, Yamagata Prefectural Institute of Public Health
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12
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Abstract
A dataset of bacterial diversity found in mites was compiled from 193 publications (from 1964 to January 2015). A total of 143 mite species belonging to the 3 orders (Mesostigmata, Sarcoptiformes and Trombidiformes) were recorded and found to be associated with approximately 150 bacteria species (in 85 genera, 51 families, 25 orders and 7 phyla). From the literature, the intracellular symbiont Cardinium, the scrub typhus agent Orientia, and Wolbachia (the most prevalent symbiont of arthropods) were the dominant mite-associated bacteria, with approximately 30 mite species infected each. Moreover, a number of bacteria of medical and veterinary importance were also reported from mites, including species from the genera Rickettsia, Anaplasma, Bartonella, Francisella, Coxiella, Borrelia, Salmonella, Erysipelothrix and Serratia. Significant differences in bacterial infection patterns among mite taxa were identified. These data will not only be useful for raising awareness of the potential for mites to transmit disease, but also enable a deeper understanding of the relationship of symbionts with their arthropod hosts, and may facilitate the development of intervention tools for disease vector control. This review provides a comprehensive overview of mite-associated bacteria and is a valuable reference database for future research on mites of agricultural, veterinary and/or medical importance.
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