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Adcox HE, Hunt JR, Allen PE, Siff TE, Rodino KG, Ottens AK, Carlyon JA. Orientia tsutsugamushi Ank5 promotes NLRC5 cytoplasmic retention and degradation to inhibit MHC class I expression. Nat Commun 2024; 15:8069. [PMID: 39277599 PMCID: PMC11401901 DOI: 10.1038/s41467-024-52119-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2023] [Accepted: 08/27/2024] [Indexed: 09/17/2024] Open
Abstract
How intracellular bacteria subvert the major histocompatibility complex (MHC) class I pathway is poorly understood. Here, we show that the obligate intracellular bacterium Orientia tsutsugamushi uses its effector protein, Ank5, to inhibit nuclear translocation of the MHC class I gene transactivator, NLRC5, and orchestrate its proteasomal degradation. Ank5 uses a tyrosine in its fourth ankyrin repeat to bind the NLRC5 N-terminus while its F-box directs host SCF complex ubiquitination of NLRC5 in the leucine-rich repeat region that dictates susceptibility to Orientia- and Ank5-mediated degradation. The ability of O. tsutsugamushi strains to degrade NLRC5 correlates with ank5 genomic carriage. Ectopically expressed Ank5 that can bind but not degrade NLRC5 protects the transactivator during Orientia infection. Thus, Ank5 is an immunoevasin that uses its bipartite architecture to rid host cells of NLRC5 and reduce surface MHC class I molecules. This study offers insight into how intracellular pathogens can impair MHC class I expression.
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Affiliation(s)
- Haley E Adcox
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, School of Medicine, Charlottesville, VA, USA
| | - Jason R Hunt
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Paige E Allen
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Thomas E Siff
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Kyle G Rodino
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
- Department of Pathology and Laboratory Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA
| | - Andrew K Ottens
- Department of Anatomy and Neurobiology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA
| | - Jason A Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, VA, USA.
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Qian J, Wu Y, Zhu C, Chen Q, Chu H, Liu L, Wang C, Luo Y, Yue N, Li W, Yang X, Yi J, Ye F, He J, Qi Y, Lu F, Wang C, Tan W. Spatiotemporal heterogeneity and long-term impact of meteorological, environmental, and socio-economic factors on scrub typhus in China from 2006 to 2018. BMC Public Health 2024; 24:538. [PMID: 38383355 PMCID: PMC10880311 DOI: 10.1186/s12889-023-17233-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2023] [Accepted: 11/15/2023] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND Large-scale outbreaks of scrub typhus combined with its emergence in new areas as a vector-borne rickettsiosis highlight the ongoing neglect of this disease. This study aims to explore the long-term changes and regional leading factors of scrub typhus in China, with the goal of providing valuable insights for disease prevention and control. METHODS This study utilized a Bayesian space-time hierarchical model (BSTHM) to examine the spatiotemporal heterogeneity of scrub typhus and analyze the relationship between environmental factors and scrub typhus in southern and northern China from 2006 to 2018. Additionally, a GeoDetector model was employed to assess the predominant influences of geographical and socioeconomic factors in both regions. RESULTS Scrub typhus exhibits a seasonal pattern, typically occurring during the summer and autumn months (June to November), with a peak in October. Geographically, the high-risk regions, or hot spots, are concentrated in the south, while the low-risk regions, or cold spots, are located in the north. Moreover, the distribution of scrub typhus is influenced by environment and socio-economic factors. In the north and south, the dominant factors are the monthly normalized vegetation index (NDVI) and temperature. An increase in NDVI per interquartile range (IQR) leads to a 7.580% decrease in scrub typhus risk in northern China, and a 19.180% increase in the southern. Similarly, of 1 IQR increase in temperature reduces the risk of scrub typhus by 10.720% in the north but increases it by 15.800% in the south. In terms of geographical and socio-economic factors, illiteracy rate and altitude are the key determinants in the respective areas, with q-values of 0.844 and 0.882. CONCLUSIONS These results indicated that appropriate climate, environment, and social conditions would increase the risk of scrub typhus. This study provided helpful suggestions and a basis for reasonably allocating resources and controlling the occurrence of scrub typhus.
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Affiliation(s)
- Jiaojiao Qian
- Department of Epidemiology, School of Public Health, Nanjing Medical University, Nanjing, China
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Yifan Wu
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Changqiang Zhu
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Qiong Chen
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Hongliang Chu
- Center for Disease Prevention and Control of Jiangsu Province, Nanjing, Jiangsu, China
| | - Licheng Liu
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Chongcai Wang
- Hainan International Travel Healthcare Center, Haikou, Hainan, China
| | - Yizhe Luo
- Department of Epidemiology, School of Public Health, Nanjing Medical University, Nanjing, China
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Na Yue
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Wenhao Li
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Xiaohong Yang
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Jing Yi
- Department of Transfusion Medicine, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, China
| | - Fuqiang Ye
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Ji He
- Xiamen International Travel Health Care Center (Xiamen Customs Port Outpatient Department), Xiamen, China
| | - Yong Qi
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China
| | - Fei Lu
- College of Information Engineering, Zhejiang University of Technology, Liuhe Rd. 288, Hangzhou, 310023, China.
| | - Chunhui Wang
- Department of Epidemiology, School of Public Health, Nanjing Medical University, Nanjing, China.
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China.
| | - Weilong Tan
- Department of Epidemiology, School of Public Health, Nanjing Medical University, Nanjing, China.
- Nanjing Bioengineering (Gene) Technology Center for Medicines, Nanjing, China.
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Silva-Ramos CR, Faccini-Martínez ÁA, Serna-Rivera CC, Mattar S, Hidalgo M. Etiologies of Zoonotic Tropical Febrile Illnesses That Are Not Part of the Notifiable Diseases in Colombia. Microorganisms 2023; 11:2154. [PMID: 37763998 PMCID: PMC10535066 DOI: 10.3390/microorganisms11092154] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Revised: 06/15/2023] [Accepted: 06/15/2023] [Indexed: 09/29/2023] Open
Abstract
In Colombia, tropical febrile illnesses represent one of the most important causes of clinical attention. Febrile illnesses in the tropics are mainly zoonotic and have a broad etiology. The Colombian surveillance system monitors some notifiable diseases. However, several etiologies are not monitored by this system. In the present review, we describe eleven different etiologies of zoonotic tropical febrile illnesses that are not monitored by the Colombian surveillance system but have scientific, historical, and contemporary data that confirm or suggest their presence in different regions of the country: Anaplasma, Arenavirus, Bartonella, relapsing fever group Borrelia, Coxiella burnetii, Ehrlichia, Hantavirus, Mayaro virus, Orientia, Oropouche virus, and Rickettsia. These could generate a risk for the local population, travelers, and immigrants, due to which they should be included in the mandatory notification system, considering their importance for Colombian public health.
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Affiliation(s)
- Carlos Ramiro Silva-Ramos
- Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 110231, Colombia;
| | - Álvaro A. Faccini-Martínez
- Servicio de Infectología, Hospital Militar Central, Bogotá 110110, Colombia;
- Servicios y Asesorías en Infectología—SAI, Bogotá 110110, Colombia
| | - Cristian C. Serna-Rivera
- Grupo de Investigación en Ciencias Veterinarias (CENTAURO), Línea de Investigación Zoonosis Emergentes y Re-Emergentes, Facultad de Ciencias Agrarias, Universidad de Antioquia, Medellín 050034, Colombia;
- Grupo de Investigación en Genética, Biodiversidad y Manejo de Ecosistemas (GEBIOME), Departamento de Ciencias Biológicas, Facultad de Ciencias Exactas y Naturales, Universidad de Caldas, Manizales 170004, Colombia
| | - Salim Mattar
- Instituto de Investigaciones Biológicas del Trópico, Universidad de Córdoba, Montería 230001, Colombia;
| | - Marylin Hidalgo
- Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá 110231, Colombia;
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Wei X, He J, Yin W, Soares Magalhaes RJ, Wang Y, Xu Y, Wen L, Sun Y, Zhang W, Sun H. Spatiotemporal dynamics and environmental determinants of scrub typhus in Anhui Province, China, 2010-2020. Sci Rep 2023; 13:2131. [PMID: 36747027 PMCID: PMC9902522 DOI: 10.1038/s41598-023-29373-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Accepted: 02/03/2023] [Indexed: 02/08/2023] Open
Abstract
This study aims to describe the epidemiological characteristics of scrub typhus, detect the spatio-temporal patterns of scrub typhus at county level, and explore the associations between the environmental variables and scrub typhus cases in Anhui Province. Time-series analysis, spatial autocorrelation analysis, and space-time scan statistics were used to explore the characteristics and spatiotemporal patterns of the scrub typhus in Anhui Province. Negative binomial regression analysis was used to explore the association between scrub typhus and environmental variables. A total of 16,568 clinically diagnosed and laboratory-confirmed cases were reported from 104 counties of 16 prefecture-level cities. The number of female cases was higher than male cases, with a proportion of 1.32:1. And the proportion of cases over 65 years old was the highest, accounting for 33.8% of the total cases. Two primary and five secondary high-risk clusters were detected in the northwestern, northeastern, and central-eastern parts of Anhui Province. The number of cases in primary and secondary high-risk clusters accounted for 60.27% and 3.00%, respectively. Scrub typhus incidence in Anhui Province was positively correlated with the population density, normalized difference vegetation index, and several meteorological variables. The mean monthly sunshine duration with 3 lags (SSD_lag3), mean monthly ground surface temperature with 1 lag (GST_lag1), and mean monthly relative humidity with 3 lags (RHU_lag3) had the most significant association with increased cases of scrub typhus. Our findings indicate that public health interventions need to be focused on the elderly farmers in north of the Huai River in Anhui Province.
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Affiliation(s)
- Xianyu Wei
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China.,Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Junyu He
- Ocean College, Zhejiang University, Zhoushan, China.,Ocean Academy, Zhejiang University, Zhoushan, China
| | - Wenwu Yin
- Chinese Center for Disease Control and Prevention, Beijing, China
| | - Ricardo J Soares Magalhaes
- Spatial Epidemiology Laboratory, School of Veterinary Science, The University of Queensland, Brisbane, Australia.,Child Health Research Center, The University of Queensland, Brisbane, Australia
| | - Yanding Wang
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Yuanyong Xu
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Liang Wen
- Chinese PLA Center for Disease Control and Prevention, Beijing, China
| | - Yehuan Sun
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China
| | - Wenyi Zhang
- Chinese PLA Center for Disease Control and Prevention, Beijing, China.
| | - Hailong Sun
- Department of Epidemiology and Biostatistics, School of Public Health, Anhui Medical University, Hefei, China. .,Chinese PLA Center for Disease Control and Prevention, Beijing, China.
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Faccini-Martínez ÁA, Silva-Ramos CR, Blanton LS, Arroyave E, Martínez-Diaz HC, Betancourt-Ruiz P, Hidalgo M, Walker DH. Serologic Evidence of Orientia Infection among Rural Population, Cauca Department, Colombia. Emerg Infect Dis 2023; 29:456-459. [PMID: 36692499 PMCID: PMC9881757 DOI: 10.3201/eid2902.221458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
We assessed serum samples collected in Cauca Department, Colombia, from 486 persons for Orientia seroreactivity. Overall, 13.8% showed reactive IgG by indirect immunofluorescence antibody assay and ELISA. Of those samples, 30% (20/67) were confirmed to be positive by Western blot, showing >1 reactive band to Orientia 56-kD or 47-kD antigens.
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Orientia tsutsugamushi OtDUB Is Expressed and Interacts with Adaptor Protein Complexes during Infection. Infect Immun 2022; 90:e0046922. [PMID: 36374099 PMCID: PMC9753657 DOI: 10.1128/iai.00469-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Orientia tsutsugamushi is an etiologic agent of scrub typhus, a globally emerging rickettsiosis that can be fatal. The bacterium's obligate intracellular lifestyle requires its interaction with host eukaryotic cellular pathways. The proteins it employs to do so and their functions during infection are understudied. Recombinant versions of the recently characterized O. tsutsugamushi deubiquitylase (OtDUB) exhibit high-affinity ubiquitin binding, mediate guanine nucleotide exchange to activate Rho GTPases, bind clathrin adaptor protein complexes 1 and 2, and bind the phospholipid phosphatidylserine. Whether OtDUB is expressed and its function during O. tsutsugamushi infection have yet to be explored. Here, OtDUB expression, location, and interactome during infection were examined. O. tsutsugamushi transcriptionally and translationally expresses OtDUB throughout infection of epithelial, monocytic, and endothelial cells. Results from structured illumination microscopy, surface trypsinization of intact bacteria, and acetic acid extraction of non-integral membrane proteins indicate that OtDUB peripherally associates with the O. tsutsugamushi cell wall and is at least partially present on the bacterial surface. Analyses of the proteins with which OtDUB associates during infection revealed several known O. tsutsugamushi cell wall proteins and others. It also forms an interactome with adapter protein complex 2 and other endosomal membrane traffic regulators. This study documents the first interactors of OtDUB during O. tsutsugamushi infection and establishes a strong link between OtDUB and the host endocytic pathway.
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Bhandari M, Singh RK, Laishevtcev A, Mohapatra TM, Nigam M, Mori E, Vasconcelos de Lacerda BCG, Coutinho HDM, Mishra AP. Revisiting scrub typhus: A neglected tropical disease. Comp Immunol Microbiol Infect Dis 2022; 90-91:101888. [PMID: 36252451 DOI: 10.1016/j.cimid.2022.101888] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/18/2022] [Accepted: 09/29/2022] [Indexed: 02/08/2023]
Abstract
Scrub typhus is an under diagnosed re-emerging vector borne disease caused by an intracellular gram negative bacteria, Orientia. The disease is commonly prevalent in rural and hilly areas of Tsutsugumashi triangle. The diagnosis of the disease is very challenging due to similarity of its early symptoms with other febrile illnesses, like dengue and COVID 19, as well as non-availability of rapid, reliable and cost-effective methods. Moreover, the diverse clinical presentation in severe cases make it significant health problem. The occupational and behavioral risks responsible for the transmission lead to urgent need of vaccine development against the disease. The complete knowledge about its pathogenesis and the interaction with host's immune cells may help the scientists in developing the appropriate diagnostic methods as well as the vaccines.
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Affiliation(s)
- Munni Bhandari
- Department of Microbiology, School of Life Sciences, Hemvati Nandan Bahuguna Garhwal University, Srinagar (Garhwal) 246174, India.
| | - Rahul Kunwar Singh
- Department of Microbiology, School of Life Sciences, Hemvati Nandan Bahuguna Garhwal University, Srinagar (Garhwal) 246174, India.
| | - Alexey Laishevtcev
- Federal Research Center - All-Russian Scientific Research Institute of Experimental Veterinary Medicine named after K.I. Skryabin and Y.R. Kovalenko of the Russian Academy of Sciences, Moscow, Russia; Laboratory of Biocontrol and Antimicrobial Resistance, Orel State, University Named After I.S. Turgenev, Orel, Russia.
| | - Tribhuvan Mohan Mohapatra
- Department of Microbiology, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India.
| | - Manisha Nigam
- Department of Biochemistry, Hemvati Nandan Bahuguna Garhwal University, Srinagar Garhwal-246174, Uttarakhand, India.
| | - Edna Mori
- CECAPE - College of Dentistry, Av. Padre Cícero, 3917, Juazeiro do Norte, São José CE 63024-015, Brazil.
| | | | | | - Abhay Prakash Mishra
- Department of Pharmacology, Faculty of Health Science, University of Free State, Bloemfontein 9300, South Africa.
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Jiang J, Martínez-Valdebenito C, Weitzel T, Farris CM, Acosta-Jamett G, Abarca K, Richards AL. Development of a New Genus-Specific Quantitative Real-Time PCR Assay for the Diagnosis of Scrub Typhus in South America. Front Med (Lausanne) 2022; 9:831045. [PMID: 35573006 PMCID: PMC9095740 DOI: 10.3389/fmed.2022.831045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Accepted: 04/05/2022] [Indexed: 12/02/2022] Open
Abstract
Scrub typhus is a potentially severe rickettsiosis, caused by Orientia tsutsugamushi in the Asia-Pacific region. Recently, however, two distinct pathogens, “Candidatus Orientia chuto” and “Candidatus Orientia chiloensis”, have been discovered in the Middle East and South America, respectively. Since the novel pathogens differ significantly from O. tsutsugamushi, many established diagnostic methods are unreliable. This work describes the development and validation of a new quantitative real-time PCR (qPCR) assay (Orien16S) for the detection of all known Orientia species. Based on a 94 bp sequence of the 16S rRNA gene (rrs), Orien16S recognized DNA samples from O. tsutsugamushi (n = 41), Ca. O. chiloensis (n = 5), and Ca. O. chuto (n = 1), but was negative for DNA preparations from closely related rickettsiae and other members of the order Rickettsiales (n = 22) as well as unrelated bacterial species (n = 11). After its implementation in Chile, the assay was verified, correctly identifying all tested eschar and buffy coat samples (n = 28) of clinical suspected cases. Furthermore, Orien16S detected Orientia DNA in trombiculid mites collected in endemic regions in southern Chile. The presented novel qPCR assay provides a useful tool for detecting Orientia and diagnosing scrub typhus from all geographical regions.
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Affiliation(s)
- Ju Jiang
- Naval Medical Research Center, Silver Spring, MD, United States.,The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Constanza Martínez-Valdebenito
- Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | | | - Gerardo Acosta-Jamett
- Instituto de Medicina Preventiva Veterinaria, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.,Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Katia Abarca
- Departamento de Enfermedades Infecciosas e Inmunología Pediátrica, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Allen L Richards
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States.,Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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Functional Characterization of Non-Ankyrin Repeat Domains of Orientia tsutsugamushi Ank Effectors Reveals Their Importance for Molecular Pathogenesis. Infect Immun 2022; 90:e0062821. [PMID: 35435726 DOI: 10.1128/iai.00628-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Orientia tsutsugamushi is a genetically intractable obligate intracellular bacterium, causes scrub typhus, and has one of the largest known armamentariums of ankyrin repeat-containing effectors (Anks). Most have a C-terminal F-box presumed to interact with the SCF ubiquitin ligase complex primarily based on their ability to bind overexpressed Skp1. Whether all F-box-containing Anks bind endogenous SCF components and the F-box residues essential for such interactions has gone unexplored. Many O. tsutsugamushi Ank F-boxes occur as part of a PRANC (pox protein repeats of ankyrin-C-terminal) domain. Roles of the non-F-box portion of the PRANC and intervening sequence region (ISR) that links the ankyrin repeat and F-box/PRANC domains are unknown. The functional relevance of these effectors' non-ankyrin repeat domains was investigated. The F-box was necessary for Flag-tagged versions of most F-box-containing Anks to precipitate endogenous Skp1, Cul1, and/or Rbx1, while the ISR and PRANC were dispensable. Ank toxicity in yeast was predominantly F-box dependent. Interrogations of Ank1, Ank5, and Ank6 established that L1, P2, E4, I9, and D17 of the F-box consensus are key for binding native SCF components and for Ank1 and Ank6 to inhibit NF-κB. The ISR is also essential for Ank1 and Ank6 to impair NF-κB. Ectopically expressed Ank1 and Ank6 lacking the ISR or having a mutagenized F-box incapable of binding SCF components performed as dominant-negative inhibitors to block O. tsutsugamushi NF-κB modulation. This study advances knowledge of O. tsutsugamushi Ank functional domains and offers an approach for validating their roles in infection.
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Wang T, Meng F, Che T, Chen J, Zhang H, Ji Y, Fan Z, Zhao G, Zhang W, Jiang B, Xu Q, Lv C, Shi T, Ruan S, Liu L, Liu W, Yang Y, Fang L. Mapping the distributions of blood-sucking mites and mite-borne agents in China: a modeling study. Infect Dis Poverty 2022; 11:41. [PMID: 35397554 PMCID: PMC8994071 DOI: 10.1186/s40249-022-00966-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 03/28/2022] [Indexed: 11/10/2022] Open
Abstract
Background Emerging mite-borne pathogens and associated disease burdens in recent decades are raising serious public health concerns, yet their distributions and ecology remain under-investigated. We aim to describe the geographical distributions of blood-sucking mites and mite-borne agents and to assess their ecological niches in China. Methods We mapped 549 species of blood-sucking mites belonging to 100 genera at the county level and eight mite-associated agents detected from 36 species of blood-sucking mites in China during 1978–2020. Impacts of climatic and environmental factors on the ecology of 21 predominant vector mites and a leading pathogen, Orientia tsutsugamushi, were assessed using boosted regression tree (BRT) models, and model-predicted risks were mapped. We also estimated the model-predicted number, area and population size of affected counties for each of the 21 mite species in China. Results Laelaps echidninus is the leading mite species that potentially affects 744 million people, followed by La. jettmari (517 million) and Eulaelaps stabularis (452 million). Leptotrombidium scutellare is the mite species harboring the highest variety of mite-borne agents including four Rickettsia species and two viruses, followed by Eu. stabularis (2 agents), L. palpale (2) and La. echidninus (2). The top two agents that parasitize the largest number of mite species are O. tsutsugamushi (28 species) and hantavirus (8). Mammalian richness, annual mean temperature and precipitation of the driest quarter jointly determine the ecology of the mites, forming four clusters of major mite species with distinct geographic distributions. High-risk areas of O. tsutsugamushi are mainly distributed in southern and eastern coastal provinces where 71.5 million people live. Conclusions Ecological niches of major mite species and mite-borne pathogens are much more extensive than what have been observed, necessitating expansion of current filed surveillance. Graphic Abstract ![]()
Supplementary Information The online version contains supplementary material available at 10.1186/s40249-022-00966-0.
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Chaisiri K, Tanganuchitcharnchai A, Kritiyakan A, Thinphovong C, Tanita M, Morand S, Blacksell SD. Risk factors analysis for neglected human rickettsioses in rural communities in Nan province, Thailand: A community-based observational study along a landscape gradient. PLoS Negl Trop Dis 2022; 16:e0010256. [PMID: 35320277 PMCID: PMC8979453 DOI: 10.1371/journal.pntd.0010256] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 04/04/2022] [Accepted: 02/12/2022] [Indexed: 12/05/2022] Open
Abstract
In this study, we estimated exposure for Scrub typhus (STG), Typhus (TG) and Spotted fever groups (SFG) rickettsia using serology at a fine scale (a whole sub-district administration level) of local communities in Nan Province, Thailand. Geographical characteristics of the sub-district were divided into two landscape types: lowland agricultural area in an urbanized setting (lowland-urbanized area) and upland agricultural area located close to a protected area of National Park (upland-forested area). This provided an ideal contrast between the two landscapes with low and high levels of human-altered habitats to study in differences in disease ecology. In total, 824 serum samples of participants residing in the eight villages were tested by screening IgG ELISA, and subsequently confirmed by the gold standard IgG Immunofluorescent Assay (IFA). STG and TG IgG positivity were highest with seroprevalence of 9.8% and 9.0%, respectively; whereas SFG positivity was lower at 6.9%. Inhabitants from the villages located in upland-forested area demonstrated significantly higher STG exposure, compared to those villages in the lowland-urbanized area (chi-square = 51.97, p < 0.0001). In contrast, TG exposure was significantly higher in those villagers living in lowland-urbanized area (chi-square = 28.26, p < 0.0001). In addition to the effect of landscape types, generalized linear model (GLM) analysis identified socio-demographic parameters, i.e., gender, occupation, age, educational level, domestic animal ownership (dog, cattle and poultry) as influential factors to explain the level of rickettsial exposure (antibody titers) in the communities. Our findings raise the public health awareness of rickettsiosis as a cause of undiagnosed febrile illness in the communities. Evidence of human exposures to rickettsial pathogens were reported from a cross-sectional study at a whole sub-district scale of local communities in Nan Province, Thailand. Seroprevalence and level of rickettsial exposures demonstrated differences between the habitat types, ecological aspects and socio-demographic factors. In addition, abundance of domestic animals in the community appeared to be one of significant factors influencing levels of human exposure to rickettsial pathogens. Our findings will benefit the local public health by raising awareness of rickettsial infections as one of potential health concerns in the community. Inclusion of rickettsioses in routine laboratory diagnosis would help to differentiate unknown febrile illness and guide appropriate treatment. Further studies are required, particularly in the fields of disease ecology as well as medical and veterinary entomology, in order to better understand epidemiology and potential zoonotic transmission of these neglected rickettsioses in endemic areas.
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Affiliation(s)
- Kittipong Chaisiri
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- * E-mail: (KC); (SDB)
| | - Ampai Tanganuchitcharnchai
- Mahidol-Oxford Tropical Research Medicine Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Anamika Kritiyakan
- Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand
| | | | - Malee Tanita
- Saen Thong Health Promoting Hospital, Tha Wang Pha, Nan, Thailand
| | - Serge Morand
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Faculty of Veterinary Technology, Kasetsart University, Bangkok, Thailand
- Faculty of Veterinary Technology, CNRS ISEM–CIRAD ASTRE, Kasetsart University, Bangkok, Thailand
| | - Stuart D. Blacksell
- Mahidol-Oxford Tropical Research Medicine Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
- Center for Tropical Medicine & Global Health, Nuffield Department of Medicine, Oxford University, Oxford, United Kingdom
- * E-mail: (KC); (SDB)
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12
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Subedi P, Ghimire M, Shrestha K, Ghimire K, Adhikari S, Tiwari B. Dengue and scrub typhus co-infection causing septic shock. Oxf Med Case Reports 2021; 2021:omab115. [PMID: 34909204 PMCID: PMC8665681 DOI: 10.1093/omcr/omab115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2021] [Revised: 10/17/2021] [Accepted: 10/28/2021] [Indexed: 11/14/2022] Open
Abstract
A 33-year-old female presented with a history of high-grade fever, cough, dyspnea, joint pain and myalgia. On examination, the patient was febrile with tachycardia, hypotension and decreased oxygen saturation. Chest auscultation revealed bilateral decreased air entry with crepitation supported by bilateral pulmonary infiltrates on chest X-ray. The laboratory investigations showed leukocytosis, thrombocytopenia, transaminitis and renal impairment. The patient was treated with intravenous fluids, ceftriaxone and levofloxacin; however, there was no clinical improvement till 48 h. She was then diagnosed with scrub typhus and dengue co-infection via serologies. Doxycycline was started following which the patient improved in 24 h. Scrub typhus can present with septic shock but does not respond to the usual antibiotics and the addition of doxycycline will result in rapid clinical improvement. Co-infection with other tropical diseases such as dengue is also common, hence it is important to test based on local endemicity.
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Affiliation(s)
- Prakriti Subedi
- General Medicine, Patan Academy of Health Sciences-School of Medicine, Lalitpur, Nepal
| | - Manoj Ghimire
- General Medicine, Government of Nepal Ministry of Health and Population, Beni Hospital, Kathmandu, Nepal
| | - Karun Shrestha
- General Medicine, Patan Academy of Health Sciences-School of Medicine, Lalitpur, Nepal
| | - Kalpana Ghimire
- General Medicine, Government of Nepal Ministry of Health and Population, Illam District Hospital, Kathmandu, Nepal
| | - Sudeep Adhikari
- Internal Medicine, Patan Academy of Health Sciences-School of Medicine, Lalitpur, Nepal
| | - Bishal Tiwari
- General Medicine, Ministry of Health and Population Department of Health Services, Beni Hospital, Kathmandu, Nepal
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13
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Hunt JR, Carlyon JA. Analysis of Orientia tsutsugamushi promoter activity. Pathog Dis 2021; 79:6369350. [PMID: 34515306 DOI: 10.1093/femspd/ftab044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 09/10/2021] [Indexed: 02/07/2023] Open
Abstract
Orientia tsutsugamushi is an obligate intracellular bacterium that causes scrub typhus, a potentially fatal rickettsiosis, and for which no genetic tools exist. Critical to addressing this technical gap is to identify promoters for driving expression of antibiotic resistance and fluorescence reporter genes in O. tsutsugamushi. Such promoters would need to be highly conserved among strains, expressed throughout infection, and exhibit strong activity. We examined the untranslated regions upstream of O. tsutsugamushi genes encoding outer membrane protein A (ompA), 22-kDa type-specific antigen (tsa22) and tsa56. The bacterium transcribed all three during infection of monocytic, endothelial and epithelial cells. Examination of the upstream noncoding regions revealed putative ribosome binding sites, one set of predicted -10 and -35 sequences for ompA and two sets of -10 and -35 sequences for tsa22 and tsa56. Comparison of these regions among geographically diverse O. tsutsugamushi patient isolates revealed nucleotide identities ranging from 84.8 to 100.0%. Upon examination of the candidates for the ability to drive green fluorescence protein expression in Escherichia coli, varying activities were observed with one of the tsa22 promoters being the strongest. Identification and validation of O. tsutsugamushi promoters is an initial key step toward genetically manipulating this important pathogen.
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Affiliation(s)
- Jason R Hunt
- Department of Microbiology and Immunology, Virginia Commonwealth University (VCU) Medical Center, School of Medicine, VCU, Richmond, VA 23298, USA
| | - Jason A Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University (VCU) Medical Center, School of Medicine, VCU, Richmond, VA 23298, USA
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14
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Wilairatana P, Kuraeiad S, Rattaprasert P, Kotepui M. Prevalence of malaria and scrub typhus co-infection in febrile patients: a systematic review and meta-analysis. Parasit Vectors 2021; 14:471. [PMID: 34521454 PMCID: PMC8442375 DOI: 10.1186/s13071-021-04969-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2021] [Accepted: 08/18/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Little information is available about malaria and scrub typhus co-infection. This study aimed to investigate the pooled prevalence of malaria and scrub typhus co-infection in febrile patients. Further, it aimed to estimate the prevalence of scrub typhus infection among patients with malaria and the odds of co-infection. This will aid the diagnosis and management of co-infected patients in endemic areas. METHODS We searched for relevant studies in three databases: PubMed, Scopus, and Web of Science. We assessed the quality of the included studies using the Joanna Briggs Institute checklist for analytical cross-sectional studies. We estimated (1) the pooled prevalence of malaria and scrub typhus co-infection, (2) the pooled prevalence of scrub typhus infection in malaria-positive patients, and (3) the pooled odds of co-infection using the DerSimonian-Laird method for random-effects models. The study results and summary estimates were visualized on a forest plot as point estimates (effect size, prevalence) and 95% confidence intervals (CI). We assessed the heterogeneity of the studies by Cochrane Q or I2 statistics. We performed subgroup analyses of countries and scrub typhus diagnostic tests to explore the sources of heterogeneity of the included studies. We assessed publication bias if more than 10 studies were used to estimate the outcome. All data analyses were conducted using Stata version 14 (StataCorp, College Station, TX, USA). RESULTS Of the 542 studies retrieved from three databases, we included 14 meeting the inclusion criteria in the systematic review and meta-analysis. The pooled prevalence of malaria and scrub typhus co-infection (56 cases) among febrile patients (7920 cases) was 1% (95% CI: 0-1%, I2: 78.28%), while the pooled prevalence of scrub typhus infection (321 cases) in patients with malaria (1418 cases) was 21% (95% CI: 12-30%, I2: 98.15%). Subgroup analysis showed that the pooled prevalence of scrub typhus infection among patients with malaria in India was 8% (95% CI: 4-13%, I2: 85.87%, nine studies with 59/794 cases), while the pooled prevalence of scrub typhus infection among patients with malaria in Thailand was 35% (95% CI: 7-64%, I2: 98.9%, four studies with 262/624 cases). The co-infections did not occur by chance (P = 0.013, odds: 0.43, 95% CI: 0.22-0.84%, I2: 60.9%). In the sensitivity analysis, the pooled prevalence of malaria and scrub typhus co-infection among febrile patients was 0% (95% CI: 0-1%, I2: 59.91%). CONCLUSIONS The present study showed the pooled prevalence and a significant association between malaria and scrub typhus. The results show the status of co-infection. Further research into co-infection in endemic areas is needed, in particular, to determine whether co-infection can accelerate disease progression or protect against severe disease.
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Affiliation(s)
- Polrat Wilairatana
- Department of Clinical Tropical Medicine, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Saruda Kuraeiad
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, 80160, Thailand
| | - Pongruj Rattaprasert
- Department of Protozoology, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Manas Kotepui
- Department of Medical Technology, School of Allied Health Sciences, Walailak University, Tha Sala, Nakhon Si Thammarat, 80160, Thailand.
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15
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Weitzel T, Silva-de la Fuente MC, Martínez-Valdebenito C, Stekolnikov AA, Pérez C, Pérez R, Vial C, Abarca K, Acosta-Jamett G. Novel vector of scrub typhus in subantarctic Chile - evidence from human exposure. Clin Infect Dis 2021; 74:1862-1865. [PMID: 34453514 DOI: 10.1093/cid/ciab748] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2021] [Indexed: 11/15/2022] Open
Abstract
The exposure of a research team to chigger mites in southern Chile allowed the first identification of a trombiculid species as vector and reservoir of scrub typhus outside the tsutsugamushi triangle, providing unique insights into the ecology and transmission of this recently discovered rickettsial infection in South America.
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Affiliation(s)
- Thomas Weitzel
- Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | | | | | | | - Caricia Pérez
- Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Ruth Pérez
- Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Cecilia Vial
- Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Katia Abarca
- Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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16
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Linsuwanon P, Wongwairot S, Auysawasdi N, Monkanna T, Richards AL, Leepitakrat S, Sunyakumthorn P, Im-Erbsin R, Poole-Smith K, McCardle P. Establishment of a Rhesus Macaque Model for Scrub Typhus Transmission: Pilot Study to Evaluate the Minimal Orientia tsutsugamushi Transmission Time by Leptotrombidium chiangraiensis Chiggers. Pathogens 2021; 10:pathogens10081028. [PMID: 34451491 PMCID: PMC8402083 DOI: 10.3390/pathogens10081028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 08/02/2021] [Accepted: 08/10/2021] [Indexed: 11/16/2022] Open
Abstract
Recently, an intradermal inoculation of the rhesus macaque model of scrub typhus has been characterized at our institution. The current project was to establish a rhesus macaque model of scrub typhus using the naturally infected chigger challenge method that faithfully mimics the natural route of pathogen transmission to fully understand the host-pathogen-vector interactions influencing pathogen transmission. Unlike the needle-based inoculation route, Orientia tsutsugamushi-infected chiggers introduce both pathogen and chigger saliva into the host epidermis at the bite site. However, information on the interaction or influence of chigger saliva on pathogenesis and immunity of host has been limited, consequently hindering vaccine development and transmission-blocking studies. To characterize chigger inoculated O. tsutsugamushi in rhesus macaques, we determined the minimum chigger attachment time required to efficiently transmit O. tsutsugamushi to the immunocompetent hosts and preliminary assessed clinical parameters, course of bacterial infection, and host’s immunological response to identifying potential factors influencing pathogen infection. Chigger infestation on hosts resulted in: (i) Rapid transmission of O. tsutsugamushi within 1 h and (ii) antigen-specific type I and II T-cell responses were markedly increased during the acute phase of infection, suggesting that both systems play critical roles in response to the pathogen control during the primary infection. In summary, we demonstrate that O. tsutsugamushi infection in rhesus macaques via chigger challenge recapitulates the time of disease onset and bacteremia observed in scrub typhus patients. Levels of proinflammatory cytokines and chemokines were positively correlated with bacteremia.
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Affiliation(s)
- Piyada Linsuwanon
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
- Correspondence:
| | - Sirima Wongwairot
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
| | - Nutthanun Auysawasdi
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
| | - Taweesak Monkanna
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
| | - Allen L. Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of Health Sciences, Bethesda, MD 20814, USA;
| | - Surachai Leepitakrat
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
| | - Piyanate Sunyakumthorn
- Department of Veterinary Medicine, USAMD-AFRIMS, Bangkok 10330, Thailand; (P.S.); (R.I.-E.)
| | - Rawiwan Im-Erbsin
- Department of Veterinary Medicine, USAMD-AFRIMS, Bangkok 10330, Thailand; (P.S.); (R.I.-E.)
| | - Katie Poole-Smith
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
| | - Patrick McCardle
- Department of Entomology, USAMD-AFRIMS, Bangkok 10330, Thailand; (S.W.); (N.A.); (T.M.); (S.L.); (K.P.-S.); (P.M.)
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17
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Orientia tsutsugamushi Nucleomodulin Ank13 Exploits the RaDAR Nuclear Import Pathway To Modulate Host Cell Transcription. mBio 2021; 12:e0181621. [PMID: 34340535 PMCID: PMC8406279 DOI: 10.1128/mbio.01816-21] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Orientia tsutsugamushi is the etiologic agent of scrub typhus, the deadliest of all diseases caused by obligate intracellular bacteria. Nucleomodulins, bacterial effectors that dysregulate eukaryotic transcription, are being increasingly recognized as key virulence factors. How they translocate into the nucleus and their functionally essential domains are poorly defined. We demonstrate that Ank13, an O. tsutsugamushi effector conserved among clinical isolates and expressed during infection, localizes to the nucleus in an importin β1-independent manner. Rather, Ank13 nucleotropism requires an isoleucine at the thirteenth position of its fourth ankyrin repeat, consistent with utilization of eukaryotic RaDAR (RanGDP-ankyrin repeats) nuclear import. RNA-seq analyses of cells expressing green fluorescent protein (GFP)-tagged Ank13, nucleotropism-deficient Ank13I127R, or Ank13ΔF-box, which lacks the F-box domain essential for interacting with SCF ubiquitin ligase, revealed Ank13 to be a nucleomodulin that predominantly downregulates transcription of more than 2,000 genes. Its ability to do so involves its nucleotropism and F-box in synergistic and mutually exclusive manners. Ank13 also acts in the cytoplasm to dysregulate smaller cohorts of genes. The effector’s toxicity in yeast heavily depends on its F-box and less so on its nucleotropism. Genes negatively regulated by Ank13 include those involved in the inflammatory response, transcriptional control, and epigenetics. Importantly, the majority of genes that GFP-Ank13 most strongly downregulates are quiescent or repressed in O. tsutsugamushi-infected cells when Ank13 expression is strongest. Ank13 is the first nucleomodulin identified to coopt RaDAR and a multifaceted effector that functions in the nucleus and cytoplasm via F-box-dependent and -independent mechanisms to globally reprogram host cell transcription.
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18
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Tantibhedhyangkul W, Matamnan S, Longkunan A, Boonwong C, Khowawisetsut L. Endothelial Activation in Orientia tsutsugamushi Infection Is Mediated by Cytokine Secretion From Infected Monocytes. Front Cell Infect Microbiol 2021; 11:683017. [PMID: 34368012 PMCID: PMC8340038 DOI: 10.3389/fcimb.2021.683017] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Accepted: 07/06/2021] [Indexed: 12/24/2022] Open
Abstract
Scrub typhus, caused by Orientia tsutsugamushi, is a common systemic infection in Asia. Delay in diagnosis and treatment can lead to vasculitis in the visceral organs and other complications. The mechanisms that drive endothelial activation and the inflammatory response in O. tsutsugamushi infection remain unknown. In addition, the interaction between monocytes and endothelial cells is still unclear. Here we demonstrate that O. tsutsugamushi-infected human dermal microvascular endothelial cells produced moderate levels of chemokines and low levels of IL-6 and IFN-β, but not TNF or IL-1β. Recombinant TNF and cytokine-rich supernatants from infected monocytes markedly enhanced chemokine production in infected endothelial cells. We also show that TNF and monocyte supernatants, but not O. tsutsugamushi infection of endothelial cells per se, upregulated the endothelial cell surface expression of ICAM-1, E-selectin, and tissue factor. This finding was consistent with the inability of O. tsutsugamushi to induce cytokine secretion from endothelial cells. The upregulation of surface molecules after stimulation with monocyte supernatants was significantly reduced by neutralizing anti-TNF antibodies. These results suggest that endothelial cell activation and response are mainly mediated by inflammatory cytokines secreted from monocytes.
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Affiliation(s)
- Wiwit Tantibhedhyangkul
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Sutthicha Matamnan
- Graduate Program in Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.,Research Division, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Asma Longkunan
- Department of Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.,Graduate Program in Immunology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Chawikan Boonwong
- Research Division, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Ladawan Khowawisetsut
- Department of Parasitology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand
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19
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Silva-Ramos CR, Jacinavicius FDC, Weitzel T, Walker DH, Faccini-Martínez ÁA. Scrub typhus: A new cause of acute undifferentiated febrile illness in Latin America? Travel Med Infect Dis 2021; 43:102138. [PMID: 34260988 DOI: 10.1016/j.tmaid.2021.102138] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 07/07/2021] [Indexed: 01/31/2023]
Affiliation(s)
- Carlos Ramiro Silva-Ramos
- Grupo de Enfermedades Infecciosas, Departamento de Microbiología, Facultad de Ciencias, Pontificia Universidad Javeriana, Bogotá, Colombia
| | | | - Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad Del Desarrollo, Santiago, Chile; Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad Del Desarrollo, Santiago, Chile.
| | - David H Walker
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA
| | - Álvaro A Faccini-Martínez
- Department of Pathology, University of Texas Medical Branch, Galveston, TX, USA; Committee of Tropical Medicine, Zoonoses and Travel Medicine, Asociación Colombiana de Infectología, Bogotá, Colombia.
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20
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Abarca K, Martínez-Valdebenito C, Angulo J, Jiang J, Farris CM, Richards AL, Acosta-Jamett G, Weitzel T. Molecular Description of a Novel Orientia Species Causing Scrub Typhus in Chile. Emerg Infect Dis 2021; 26:2148-2156. [PMID: 32818400 PMCID: PMC7454112 DOI: 10.3201/eid2609.200918] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Scrub typhus is a potentially fatal rickettsiosis caused by Orientia species intracellular bacteria of the genus Orientia. Although considered to be restricted to the Asia Pacific region, scrub typhus has recently been discovered in southern Chile. We analyzed Orientia gene sequences of 16S rRNA (rrs) and 47-kDa (htrA) from 18 scrub typhus patients from Chile. Sequences were ≥99.7% identical among the samples for both amplified genes. Their diversity was 3.1%–3.5% for rrs and 11.2%–11.8% for htrA compared with O. tsusugamushi and 3.0% for rrs and 14.8% for htrA compared with Candidatus Orientia chuto. Phylogenetic analyses of both genes grouped the specimens from Chile in a different clade from other Orientia species. Our results indicate that Orientia isolates from Chile constitute a novel species, which, until they are cultivated and fully characterized, we propose to designate as Candidatus Orientia chiloensis, after the Chiloé Archipelago where the pathogen was identified.
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21
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S DC, A C, C UC, E HH, V G, I S, N SP, D PM, D GA, C N, J V, G AJ, D V, J M. Mapping the distribution and risk factors of Anaplasmataceae in wild and domestic canines in Chile and their association with Rhipicephalus sanguineus species complex lineages. Ticks Tick Borne Dis 2021; 12:101752. [PMID: 34134063 DOI: 10.1016/j.ttbdis.2021.101752] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Revised: 04/19/2021] [Accepted: 05/02/2021] [Indexed: 12/11/2022]
Abstract
Anaplasma platys and Ehrlichia canis are members of the Anaplasmataceae family that cause disease in dogs and are mainly transmitted by Rhipicephalus sanguineus species group ticks. We performed a cross-sectional study on these pathogens across six bioclimatic regions of Chile, including 719 free-ranging rural dogs, 132 Andean foxes (Lycalopex culpaeus), and 82 South American gray foxes (Lycalopex griseus). Dog and fox blood samples were first screened for DNA of Anaplasmataceae followed by two Ehrlichia-specific protocols. Antibodies against Anaplasma sp. and E. canis were assessed by immunofluorescence in dogs. Ectoparasites were collected and identified, with the determination of the lineages of the Rhipicephalus sanguineus species group by molecular and phylogenetic analyses. Finally, potential risk factors for infection were investigated across the different bioclimatic regions and host species. All DNA amplicons obtained from the screening protocol corresponded to Anaplasma platys. The occurrence of both A. platys DNA and antibodies was confirmed in all six bioclimatic regions, except for regions at high altitude and/or without either R. sanguineus species group lineage present. Dogs infested with R. sanguineus ticks were significantly more prone to be infected and exposed to Anaplasma spp. Prevalence of DNA was significantly higher in juvenile (19%) than in adult dogs (9%), whereas the opposite was found for seroprevalence (19% versus 35%, respectively). Overall prevalence of A. platys DNA was higher in dogs (11%) than in foxes (4%), probably owing to markedly lower tick infestations in the foxes. Ehrlichia canis DNA was not detected in any sample, and antibodies against this pathogen were detected only in four dogs, in areas with both R. sanguineus lineages present. Free-ranging dogs in Chile could be favoring the maintenance of A. platys in all areas suitable for its tick vector. Although apparently infrequent, spillovers from dogs to foxes may be taking place and should be considered in management plans in Chile.
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Affiliation(s)
- Di Cataldo S
- Conservation Medicine, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 252, Santiago, Chile.
| | - Cevidanes A
- Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile; Department of Animal Health. NEIKER-Basque Institute for Agricultural Research and Development. Basque Research and Technology Alliance (BRTA). Parque Científico y Tecnológico de Bizkaia, P812, 48160 Derio, Spain
| | - Ulloa-Contreras C
- Facultad de Ciencias Veterinarias y Pecuarias, Universidad de Chile, Santa Rosa 11735, La Pintana, Santiago, Chile
| | - Hidalgo-Hermoso E
- Conservation and Research Department, Parque Zoológico Buin Zoo, Panamericana Sur Km 32, Buin, Chile
| | - Gargano V
- Centro di Referenza Nazionale per Anaplasma, Babesia, Rickettsia, e Theileria, Istituto zooprofilattico sperimentale della Sicilia, via Gino Marinuzzi, 3, Palermo, Sicilia, Italy
| | - Sacristán I
- Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile
| | - Sallaberry-Pincheira N
- Unidad de Rehabilitación de Fauna Silvestre, Escuela de Medicina Veterinaria, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 252, Santiago, Chile
| | - Peñaloza-Madrid D
- Parque Safari Chile, Ruta H-30, Km 5, Camino A Doñihue S/N, Rancagua, O'Higgins, Chile
| | - González-Acuña D
- Departamento de Ciencias Pecuarias, Facultad de Medicina Veterinaria, 71 Universidad de Concepción, Chillán, Chile
| | - Napolitano C
- Departamento de Ciencias Biológicas y Biodiversidad, Universidad de Los Lagos, Av. Fuchslocher 1305, Osorno, Chile; Instituto de Ecología y Biodiversidad, Santiago, Chile
| | - Vianna J
- Departamento de Ecosistemas y Medio Ambiente, Facultad de Agronomía e Ingeniería Forestal, Pontificia Universidad Católica de Chile, Av. Vicuña Mackenna 4860, Santiago, Chile
| | - Acosta-Jamett G
- Instituto de Medicina Preventiva Veterinaria y Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Casilla 567, Valdivia, Chile
| | - Vicari D
- Centro di Referenza Nazionale per Anaplasma, Babesia, Rickettsia, e Theileria, Istituto zooprofilattico sperimentale della Sicilia, via Gino Marinuzzi, 3, Palermo, Sicilia, Italy
| | - Millán J
- Facultad de Ciencias de la Vida, Universidad Andres Bello, República 440, Santiago, Chile; Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Miguel Servet 177, 50013 Zaragoza, Spain; Fundación ARAID, Avda. de Ranillas, 50018 Zaragoza, Spain
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Abstract
PURPOSE OF REVIEW Scrub typhus, caused by Orientia tsutsugamushi, is a widely neglected disease which is gaining global momentum because of its resurgence patterns. The disease is now being reported in newer regions as well as areas previously endemic areas. In this review, we aim to comprehensively review the data available to assist physicians in making an accurate diagnosis and appropriate management of the disease. RECENT FINDINGS Several diagnostic tests have been developed for confirming scrub typhus. However, there is lack of clarity on which tests are most appropriate in a given clinical scenario. A recent study has demonstrated that in early disease (<7 days) when serological tests remain negative, the quantitative polymerase chain reaction is the most sensitive test. Among the serological tests, both IgM enzyme-linked immunosorbent assay as well as rapid diagnostic tests revealed excellent sensitivities and specificities. SUMMARY With the reemergence of scrub typhus, a high degree of clinical suspicion is required to appropriately diagnose this disease which presents as an acute febrile illness. It can progress to develop various complications leading to multi-organ dysfunction syndrome. Mild illness responds well to antibiotic treatment with doxycycline and azithromycin. Further studies are required to determine the most optimal therapy in severe scrub typhus infections and superiority of one drug over the other.
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Bhandari I, Karmacharya Malla K, Ghimire P, Bhandari B. Scrub Typhus among Febrile Children in a Tertiary Care Center of Central Nepal: A Descriptive Cross-sectional Study. JNMA J Nepal Med Assoc 2021; 59:437-441. [PMID: 34508431 PMCID: PMC8673454 DOI: 10.31729/jnma.6166] [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: 02/25/2021] [Accepted: 05/12/2021] [Indexed: 11/18/2022] Open
Abstract
Introduction: Scrub typhus is a mite borne infectious disease caused by Orientia tsutsugamushi, obligate intracellular bacteria, transmitted by chigger mites. Scrub typhus is an emerging febrile illness with clinical suspicion being the only key to diagnosis. This study was conducted to find out the prevalence of Scrub typhus among febrile children in a tertiary care center of central Nepal. Methods: A descriptive cross-sectional study was conducted from January 2018 to December 2019 in the pediatric inpatients of a tertiary care hospital after obtaining ethical clearance from Institutional Review Committee of Institute (Reference number 2020-105). Convenient sampling method was used. Data was analyzed using Statistical Packages for the Social Science version 16. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data. Results: Out of 1024 febrile patients, prevalence of scrub typhus among febrile children was 55 (5.37%) (3.66-7.08 at 90% Confidence Interval). Of 55 patients, mean age was 9.2 years with 52 (94.6%) of cases diagnosed between July to November. Among 55 patients, other symptoms were vomiting 33 (60%), headache 22 (40%), abdominal pain 19 (34.5%), cough 15 (27.3%), nausea (25.5%), seizure 11 (20 %), and dyspnea 6 (10.9%). Major clinical signs was lymphadenopathy 29 (52.7%). Major complication noted was meningitis 11 (20%). Conclusions: The prevalence of scrub typhus is considerably high during July to November so it should be considered as a differential diagnosis of fever particularly in this period.
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Affiliation(s)
- Isha Bhandari
- Department of Pediatrics, College of Medical Sciences and Teaching Hospital, Bharatpur, Chitwan, Nepal
| | - Kalpana Karmacharya Malla
- Department of Pediatrics, College of Medical Sciences and Teaching Hospital, Bharatpur, Chitwan, Nepal
| | - Pukar Ghimire
- Department of Internal Medicine, College of Medical Sciences and Teaching Hospital, Bharatpur, Chitwan, Nepal
| | - Bibek Bhandari
- Department of Pediatrics, College of Medical Sciences and Teaching Hospital, Bharatpur, Chitwan, Nepal
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Linsuwanon P, Auysawasdi N, Wongwairot S, Leepitakrat S, Rodkhamtook W, Wanja E, Monkanna T, Wegner M, Davidson S, Poovorawan Y, Poole-Smith B, Limsuwon C, McCardle P. Assessing scrub typhus and rickettsioses transmission risks in the Chiang Rai province of northern Thailand. Travel Med Infect Dis 2021; 42:102086. [PMID: 34044127 DOI: 10.1016/j.tmaid.2021.102086] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 05/19/2021] [Accepted: 05/20/2021] [Indexed: 01/25/2023]
Abstract
BACKGROUND Scrub typhus is an important disease in the Asia-Pacific countries with increasing relevance for public health worldwide. Entomological risk assessment for scrub typhus and rickettsial disease in Phu Chi Fah village-Chiang Rai was performed to determine areas at greatest risk for disease transmission in order to increase awareness of diseases to travelers and healthcare workers. METHODS From 2016 to 2018, rodents and chiggers were collected from 7 sites covering residential, grassland, and forest areas to determine the prevalence of pathogen of interest. The correlation between land type and vector-host-pathogen interaction system was investigated. RESULT High prevalence of O. tsutsugamushi-infected and Rickettsia-infected chiggers was observed especially in areas with grassland and forest ecotones. Chigger and rodent species composition were negatively associated with the level of human disturbance. Increased density of rodents was responsible for a higher abundance of chigger population and increased prevalence of O. tsutsugmaushi infection in chigger in the following year. CONCLUSION Communities in the study areas have an increased exposure risk to scrub typhus and potentially spotted fever group rickettsiosis. Travellers to this endemic area should pay more attention pathogen risks so as to avoid vector and disease exposure. Seasonal rodenticidal activity may help migitate the risk of pathogen transmission.
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Affiliation(s)
- Piyada Linsuwanon
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand.
| | - Nutthanun Auysawasdi
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Sirima Wongwairot
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Surachai Leepitakrat
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Wuttikon Rodkhamtook
- Research Division, Royal Thai Army Component-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Elizabeth Wanja
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Taweesak Monkanna
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Matthew Wegner
- Department of Veterinary Medicine, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Silas Davidson
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Yong Poovorawan
- Center of Excellence in Clinical Virology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Betty Poole-Smith
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Chawin Limsuwon
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
| | - Patrick McCardle
- Department of Entomology, US Medical Directorate-Armed Forces Research Institute of Medical Science, Bangkok, Thailand
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25
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Imported scrub typhus in Europe: Report of three cases and a literature review. Travel Med Infect Dis 2021; 42:102062. [PMID: 33862243 DOI: 10.1016/j.tmaid.2021.102062] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 04/07/2021] [Accepted: 04/09/2021] [Indexed: 11/21/2022]
Abstract
BACKGROUND Scrub typhus is a vector-borne rickettsial infection, which can cause relevant morbidity and mortality. While the number of cases is around a million per year globally, the infection is seldom diagnosed in travellers from Europe. METHODS We herein report three cases diagnosed in Italian travellers and review the literature about imported cases in Europe in the last 60 years. RESULTS Three participants to the same hiking trip to the forest of northern Laos presented fever and other symptoms, including eschars (2 individuals) and skin rash (2 individuals). Overall, they didn't report complications, and recovered soon after doxycycline treatment. Diagnosis was retrospectively confirmed with PCR in one of them. The review collected data from 40 patients. Almost all of them (95%) presented fever, more than a half had headache, skin rash, eschars, arthromyalgias. 73% of them were hospitalized, and 16.2% needed intensive care. Diagnosis was confirmed by serology in almost all cases (94.6%). Most patients (88%) were treated with doxycycline. All patients survived, although one case resulted in incomplete tetraparesis. CONCLUSIONS Scrub typhus should be considered in all travellers coming back from endemic areas and presenting with acute febrile illness. Laboratory diagnosis can be challenging, as specific tests are not widely available. In case of clinical suspicion, a prompt treatment with oral doxycycline could avoid severe complications.
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26
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Wangsanut T, Brann KR, Adcox HE, Carlyon JA. Orientia tsutsugamushi modulates cellular levels of NF-κB inhibitor p105. PLoS Negl Trop Dis 2021; 15:e0009339. [PMID: 33857149 PMCID: PMC8078813 DOI: 10.1371/journal.pntd.0009339] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 04/27/2021] [Accepted: 03/29/2021] [Indexed: 11/26/2022] Open
Abstract
Background Scrub typhus is a neglected tropical disease that threatens more than one billion people. If antibiotic therapy is delayed, often due to mis- or late diagnosis, the case fatality rate can increase considerably. Scrub typhus is caused by the obligate intracellular bacterium, Orientia tsutsugamushi, which invades phagocytes and endothelial cells in vivo and diverse tissue culture cell types in vitro. The ability of O. tsutsugamushi to replicate in the cytoplasm indicates that it has evolved to counter eukaryotic host cell immune defense mechanisms. The transcription factor, NF-κB, is a tightly regulated initiator of proinflammatory and antimicrobial responses. Typically, the inhibitory proteins p105 and IκBα sequester the NF-κB p50:p65 heterodimer in the cytoplasm. Canonical activation of NF-κB via TNFα involves IKKβ-mediated serine phosphorylation of IκBα and p105, which leads to their degradation and enables NF-κB nuclear translocation. A portion of p105 is also processed into p50. O. tsutsugamushi impairs NF-κB translocation into the nucleus, but how it does so is incompletely defined. Principal findings Western blot, densitometry, and quantitative RT-PCR analyses of O. tsutsugamushi infected host cells were used to determine if the pathogen’s ability to inhibit NF-κB is linked to modulation of p105. Results demonstrate that p105 levels are elevated several-fold in O. tsutsugamushi infected HeLa and RF/6A cells with only a nominal increase in p50. The O. tsutsugamushi-stimulated increase in p105 is bacterial dose- and protein synthesis-dependent, but does not occur at the level of host cell transcription. While TNFα-induced phosphorylation of p105 serine 932 proceeds unhindered in infected cells, p105 levels remain elevated and NF-κB p65 is retained in the cytoplasm. Conclusions O. tsutsugamushi specifically stabilizes p105 to inhibit the canonical NF-κB pathway, which advances understanding of how it counters host immunity to establish infection. Scrub typhus is a neglected disease that can be fatal and occurs predominantly in the Asia-Pacific, one of the most densely populated regions of the world. Notably, cases continue to emerge outside this area. The etiologic agent is Orientia tsutsugamushi, a bacterial pathogen that infects certain leukocytes and cells that line blood vessels in animals and humans. The success of O. tsutsugamushi to colonize these cells is at least partially attributable to its ability to counter host immunity. In this study, we demonstrate that O. tsutsugamushi stabilizes p105, a mammalian inhibitor of the transcription factor, NF-κB, which is otherwise key for activating proinflammatory and antimicrobial gene expression. O. tsutsugamushi is the first example of a bacterium that inhibits NF-κB by promoting elevated levels of p105 and impairing its degradation. Our findings provide fundamental information that helps explain how this important pathogen has evolved to stealthily establish infection in host cells.
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Affiliation(s)
- Tanaporn Wangsanut
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, Unites States of America
| | - Katelynn R. Brann
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, Unites States of America
| | - Haley E. Adcox
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, Unites States of America
| | - Jason A. Carlyon
- Department of Microbiology and Immunology, Virginia Commonwealth University Medical Center, School of Medicine, Richmond, Virginia, Unites States of America
- * E-mail:
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27
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Raoult D. Rickettsioses: "A Treasure Is Hidden in This Garden". Clin Infect Dis 2021; 72:1179-1180. [PMID: 31999822 DOI: 10.1093/cid/ciaa096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 01/28/2020] [Indexed: 11/14/2022] Open
Affiliation(s)
- Didier Raoult
- Microbes, Evolution, Phylogeny and Infection, IRD, Aix Marseille University, AP-HM, Marseille, France.,IHU-Méditerranée Infection, Marseille, France
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28
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Silva-de la Fuente MC, Stekolnikov AA, Weitzel T, Beltrami E, Martínez-Valdebenito C, Abarca K, Acosta-Jamett G. Chigger Mites (Acariformes: Trombiculidae) of Chiloé Island, Chile, With Descriptions of Two New Species and New Data on the Genus Herpetacarus. JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:646-657. [PMID: 33300548 DOI: 10.1093/jme/tjaa258] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2020] [Indexed: 06/12/2023]
Abstract
Three species of chigger mites are recorded in our collections from four species of cricetid rodents on Chiloé Island (southern Chile, Los Lagos Region), an area endemic to scrub typhus (Orientia sp.). Two species are described as new-Herpetacarus (Abonnencia) eloisae sp. nov. and Quadraseta chiloensis sp. nov. One species, Paratrombicula goffiStekolnikov and González-Acuña 2012, is for the first time recorded on a mammal host (one species of cricetid rodent), and its distribution is extended to the Los Lagos Region of Chile. The genus ProschoengastiaVercammen-Grandjean, 1967 is synonymized with the subgenus Herpetacarus (Abonnencia)Vercammen-Grandjean, 1960, and four new combinations are established: Herpetacarus (Abonnencia) herniosa (Brennan and Jones, 1961), comb. nov., Herpetacarus (Abonnencia) insolita (Brennan and Jones, 1961), comb. nov., Herpetacarus (Abonnencia) macrochaeta (Brennan and Jones, 1961), comb. nov., and Herpetacarus (Abonnencia) antarctica (Stekolnikov and Gonzalez-Acuña, 2015), comb. nov.
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Affiliation(s)
| | | | - Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
- Hantavirus and Zoonoses Program, Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Esperanza Beltrami
- Instituto de Medicina Preventiva Veterinaria, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Escuela de Graduados, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Constanza Martínez-Valdebenito
- Laboratorio de Infectología y Virología Molecular, Red Salud UC-Christus, Santiago, Chile
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Katia Abarca
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gerardo Acosta-Jamett
- Instituto de Medicina Preventiva Veterinaria, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
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29
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Jiang J, Farris CM, Yeh KB, Richards AL. International Rickettsia Disease Surveillance: An Example of Cooperative Research to Increase Laboratory Capability and Capacity for Risk Assessment of Rickettsial Outbreaks Worldwide. Front Med (Lausanne) 2021; 8:622015. [PMID: 33738293 PMCID: PMC7960665 DOI: 10.3389/fmed.2021.622015] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Accepted: 01/20/2021] [Indexed: 01/30/2023] Open
Abstract
Cooperative research that addresses infectious disease surveillance and outbreak investigations relies heavily on availability and effective use of appropriate diagnostic tools, including serological and molecular assays, as exemplified by the current COVID-19 pandemic. In this paper, we stress the importance of using these assays to support collaborative epidemiological studies to assess risk of rickettsial disease outbreaks among international partner countries. Workforce development, mentorship, and training are important components in building laboratory capability and capacity to assess risk of and mitigate emerging disease outbreaks. International partnerships that fund cooperative research through mentoring and on-the-job training are successful examples for enhancing infectious disease surveillance. Cooperative research studies between the Naval Medical Research Center's Rickettsial Diseases Research Program (RDRP) and 17 institutes from nine countries among five continents were conducted to address the presence of and the risk for endemic rickettsial diseases. To establish serological and molecular assays in the collaborative institutes, initial training and continued material, and technical support were provided by RDRP. The laboratory methods used in the research studies to detect and identify the rickettsial infections included (1) group-specific IgM and IgG serological assays and (2) molecular assays. Twenty-six cooperative research projects performed between 2008 and 2020 enhanced the capability and capacity of 17 research institutes to estimate risk of rickettsial diseases. These international collaborative studies have led to the recognition and/or confirmation of rickettsial diseases within each of the partner countries. In addition, with the identification of specific pathogen and non-pathogen Rickettsia species, a more accurate risk assessment could be made in surveillance studies using environmental samples. The discoveries from these projects reinforced international cooperation benefiting not only the partner countries but also the scientific community at large through presentations (n = 40) at international scientific meetings and peer-reviewed publications (n = 18). The cooperative research studies conducted in multiple international institutes led to the incorporation of new SOPs and trainings for laboratory procedures; biosafety, biosurety, and biosecurity methods; performance of rickettsia-specific assays; and the identification of known and unknown rickettsial agents through the introduction of new serologic and molecular assays that complemented traditional microbiology methods.
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Affiliation(s)
- Ju Jiang
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, United States
- The Henry M. Jackson Foundation for the Advancement of Military Medicine, Inc., Bethesda, MD, United States
| | - Christina M. Farris
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, United States
| | | | - Allen L. Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States
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30
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Baak-Baak C, Garcia-Rejon J, Tzuc-Dzul J, Nuñez-Corea D, Arana-Guardia R, Cetina-Trejo R, Machain-Williams C, Jimenez-Coello M, Acosta-Viana K, Torres-Chable O, Pietri JE, Cigarroa-Toledo N. Four Species of Under-reported Parasitic Arthropods in Mexico and their Potential Role as Vectors of Pathogens. J Parasitol 2021; 106:835-842. [PMID: 33378530 DOI: 10.1645/20-58] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
Numerous arthropod taxa are important in human and veterinary medicine. The salivary secretions and feces of arthropods can cause allergic reactions in host vertebrates or harbor pathogens. Also, bites can be a risk factor for secondary infections. Documenting the diversity of arthropods of medical and veterinary importance remains an important aspect of disease control and prevention. We provide new records of ectoparasitic arthropods from Mexico that are of potential medical or veterinary relevance. Scanning electron microscopy along with amplification and sequencing of a fragment of the mitochondrial gene (16S rRNA) was used to confirm some species identities. We report the cat louse Felicola subrostratus from cats and the chewing louse Heterodoxus spiniger from dogs, which are common ectoparasites but largely not reported in Mexico. The chigger Eutrombicula alfreddugesi is common on wild lizards (Squamata). For the first time, E. alfreddugesi is reported on Hemidactylus frenatus (common house gecko). This reptile has a close relationship with humans and its chiggers can cause dermatitis (i.e., trombiculiasis) or transmit pathogens. In addition, the common bed bug Cimex lectularius is reported for the first time in the state of Yucatan, an atypical area for its natural distribution. Phylogenetic analysis revealed that Cimex lectularius from Yucatan is closely related to genetic sequences of Cimex lectularius from China. Knowing the regional distribution of arthropods allows the design and implementation of prevention strategies for those that have potential roles as reservoirs or vectors.
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Affiliation(s)
- Carlos Baak-Baak
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - Julian Garcia-Rejon
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - Julio Tzuc-Dzul
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - David Nuñez-Corea
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - Roger Arana-Guardia
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - Rosa Cetina-Trejo
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - Carlos Machain-Williams
- Laboratorio de Arbovirología. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Calle 43 s/n x 96, Col. Paseo de las Fuentes, Mérida, Yucatán, C.P. 97225, México
| | - Matilde Jimenez-Coello
- Laboratorio de Biología Celular. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Avenida Itzaes, No. 490 x Calle 59, Col. Centro, Mérida, Yucatán, C.P. 97000, México
| | - Karla Acosta-Viana
- Laboratorio de Biología Celular. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Avenida Itzaes, No. 490 x Calle 59, Col. Centro, Mérida, Yucatán, C.P. 97000, México
| | - Oswaldo Torres-Chable
- Laboratorio de Enfermedades Tropicales y Transmitidas por Vector, Universidad Juárez Autónoma de Tabasco, Villahermosa, Tabasco, C.P. 86040, México
| | - Jose E Pietri
- University of South Dakota, Sanford School of Medicine, Division of Basic Biomedical Sciences, 414 E. Clark Street, Vermillion, South Dakota 57069
| | - Nohemi Cigarroa-Toledo
- Laboratorio de Biología Celular. Centro de Investigaciones Regionales "Dr. Hideyo Noguchi", Universidad Autónoma de Yucatán, México, Avenida Itzaes, No. 490 x Calle 59, Col. Centro, Mérida, Yucatán, C.P. 97000, México
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31
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Lee HJ, Park C. Density of Chigger Mites as Tsutsugamushi Vectors Collected from Jinan, Jeollabuk-do. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2020. [DOI: 10.15324/kjcls.2020.52.4.364] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Hyeok Jae Lee
- Department of Biomedical Laboratory Science, Gwangju Health University, Gwangju, Korea
| | - Chul Park
- Department of Biomedical Laboratory Science, Gwangju Health University, Gwangju, Korea
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Banerjee A, Kulkarni S. Orientia tsutsugamushi: The dangerous yet neglected foe from the East. Int J Med Microbiol 2020; 311:151467. [PMID: 33338890 DOI: 10.1016/j.ijmm.2020.151467] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2019] [Revised: 10/06/2020] [Accepted: 11/25/2020] [Indexed: 01/22/2023] Open
Abstract
Orientia tsutsugamushi (OT), the causative agent of the vector-borne Scrub typhus zoonotic disease in humans, is a unique microorganism that exists in the Asia-Pacific region since a long time. In spite of its occurrence, the organism had been neglected until recent years. Humans are the accidental dead-end hosts of O. tsutsugamushi and display manifestations which are both severe and misleading. The vast antigenic diversity of OT and non-pathognomic symptoms of Scrub typhus, create hurdles in the clinical management of the disease and impede the OT-research. Many countries in the Asia-Pacific region have reported the resurgence of OT- infections and have raised concerns for its expanding distribution. This has triggered the development of advanced techniques for diagnosis and research on exploring a successful vaccine candidate to reduce the burden of the disease. Thus, the aim of this systematic review is to provide an update on the recent advances in the OT-research and highlight the key areas that have remained obscure and demand attention.
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Affiliation(s)
- Anwesha Banerjee
- ICMR-National AIDS Research Institute, Bhosari, Pune, 411026, India
| | - Smita Kulkarni
- ICMR-National AIDS Research Institute, Bhosari, Pune, 411026, India.
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Osborn J, Roberts T, Guillen E, Bernal O, Roddy P, Ongarello S, Sprecher A, Page AL, Ribeiro I, Piriou E, Tamrat A, de la Tour R, Rao VB, Flevaud L, Jensen T, McIver L, Kelly C, Dittrich S. Prioritising pathogens for the management of severe febrile patients to improve clinical care in low- and middle-income countries. BMC Infect Dis 2020; 20:117. [PMID: 32041536 PMCID: PMC7011354 DOI: 10.1186/s12879-020-4834-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2019] [Accepted: 01/28/2020] [Indexed: 11/26/2022] Open
Abstract
Background Severe febrile illness without a known source (SFWS) is a challenge for clinicians when deciding how to manage a patient, particularly given the wide spectrum of potential aetiologies that contribute to fever. These infections are difficult to distinguish clinically, and accurate diagnosis requires a plethora of diagnostics including blood cultures, imaging techniques, molecular or serological tests, and more. When laboratory services are available, a limited test menu hinders clinical decision-making and antimicrobial stewardship, leading to empiric treatment and suboptimal patient outcomes. To specifically address SFWS, this work aimed to identify priority pathogens for a globally applicable panel for fever causing pathogens. Method A pragmatic two-pronged approach combining currently available scientific data in an analytical hierarchy process and systematically gathered expert input, was designed to address the lack of comprehensive global aetiology data. The expert re-ranked list was then further adapted for a specific use case to focus on community acquired infections in whole blood specimens. The resulting list was further analysed to address different geographical regions (Asia, Africa, and Latin America), and Cohen kappa scores of agreement were calculated. Results The expert ranked prioritized pathogen list generated as part of this two-pronged approach included typhoidal Salmonella, Plasmodium species and Mycobacterium tuberculosis as the top 3 pathogens. This pathogen list was then further adapted for the SFWS use case to develop a final pathogen list to inform product development. Subsequent analysis comparing the relevance of the SFWS pathogen list to multiple populations and geographical regions showed that the SFWS prioritized list had considerable utility across Africa and Asia, but less so for Latin America. In addition, the list showed high levels of agreement across different patient sub-populations, but lower relevance for neonates and symptomatic HIV patients. Conclusion This work highlighted once again the challenges of prioritising in global health, but it also shows that taking a two-pronged approach, combining available prevalence data with expert input, can result in a broadly applicable priority list. This comprehensive utility is particularly important in the context of product development, where a sufficient market size is essential to achieve a sustainable commercialized diagnostic product to address SFWS.
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Weitzel T, Aylwin M, Martínez-Valdebenito C, Acosta-Jamett G, Abarca K. Scrub typhus in Tierra del Fuego: a tropical rickettsiosis in a subantarctic region. Clin Microbiol Infect 2020; 27:S1198-743X(20)30719-9. [PMID: 33253942 DOI: 10.1016/j.cmi.2020.11.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 11/17/2020] [Accepted: 11/23/2020] [Indexed: 10/22/2022]
Affiliation(s)
- Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile; Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.
| | - Mabel Aylwin
- Unidad de Infectología, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Constanza Martínez-Valdebenito
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Gerardo Acosta-Jamett
- Instituto de Medicina Preventiva Veterinaria y Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Katia Abarca
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, División de Pediatría, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Abstract
Over the last decades, rickettsioses are emerging worldwide. These diseases are caused by intracellular bacteria. Although rickettsioses can be treated with antibiotics, a vaccine against rickettsiae is highly desired for several reasons. Rickettsioses are highly prevalent, especially in poor countries, and there are indications of the development of antibiotic resistance. In addition, some rickettsiae can persist and cause recurrent disease. The development of a vaccine requires the understanding of the immune mechanisms that are involved in protection as well as in immunopathology. Knowledge about these immune responses is accumulating, and efforts have been undertaken to identify antigenic components of rickettsiae that may be useful as a vaccine. This review provides an overview on current knowledge of adaptive immunity against rickettsiae, which is essential for defense, rickettsial antigens that have been identified so far, and on vaccination strategies that have been used in animal models of rickettsial infections.
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Fisher J, Card G, Soong L. Neuroinflammation associated with scrub typhus and spotted fever group rickettsioses. PLoS Negl Trop Dis 2020; 14:e0008675. [PMID: 33091013 PMCID: PMC7580963 DOI: 10.1371/journal.pntd.0008675] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Scrub typhus and spotted fever rickettsioses (SFR) are understudied, vector-borne diseases of global significance. Over 1 billion individuals are at risk for scrub typhus alone in an endemic region, spanning across eastern and southern Asia to Northern Australia. While highly treatable, diagnostic challenges make timely antibiotic intervention difficult for these diseases. Delayed therapy may lead to severe outcomes affecting multiple organs, including the central nervous system (CNS), where infection and associated neuroinflammation may be lethal or lead to lasting sequelae. Meningitis and encephalitis are prevalent in both scrub typhus and SFR. Additionally, case reports detailing focal neurological deficits have come to light, with attention to both acute and chronic sequelae of infection. Despite the increasing number of clinical reports outlining neurologic consequences of these diseases, relatively little research has examined underlying mechanisms of neuroinflammation. Animal models of scrub typhus have identified cerebral T-cell infiltration and vascular damage associated with endothelial infection and neuropathogenesis. Differential gene expression analysis of brain tissues during murine scrub typhus have revealed selective increases in CXCR3 ligands, proinflammatory and type-1 cytokines and chemokines, and cytotoxicity molecules, as well as alterations in the complement pathway. In SFR, microglial expansion and macrophage infiltration contribute to neurological disease progression. This narrative Review highlights clinical neurologic features of scrub typhus and SFR and evaluates our current understanding of basic research into neuroinflammation for both diseases in animal models. Further investigation into key mediators of neuropathogenesis may yield prognostic markers and treatment regimens for severe patients.
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Affiliation(s)
- James Fisher
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Galen Card
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Lynn Soong
- Department of Microbiology and Immunology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Department of Pathology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Institute for Human Infections and Immunity, University of Texas Medical Branch, Galveston, Texas, United States of America
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Müller A, Sepúlveda P, Di Cataldo S, Cevidanes A, Lisón F, Millán J. Molecular investigation of zoonotic intracellular bacteria in Chilean bats. Comp Immunol Microbiol Infect Dis 2020; 73:101541. [PMID: 32911380 DOI: 10.1016/j.cimid.2020.101541] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/23/2020] [Accepted: 08/28/2020] [Indexed: 01/06/2023]
Abstract
Intracellular pathogens were investigated for the first time in 55 Chilean bats belonging to six species. Using a conventional PCR protocol targeting a fragment of the ITS region, 21 bats (38 %) were positive for DNA of Bartonella sp. Molecular characterization of fragments of the gltA, rpoB and fstZ genes and subsequent phylogenetic analysis indicated the presence of diverse genotypes related to Bartonella from bats worldwide. DNA from C. burnetii was investigated using a real-time PCR (qPCR) protocol targeting the IS1111 gene and yielded positive results for 5 individuals (9%), being the first report of C. burnetii in wildlife in Chile. All bats were negative for Rickettsia sp., evaluated by qPCR for the gltA gene, confirming that bats do not act as important reservoirs for Rickettsia. This preliminary survey calls for more comprehensive studies on the epidemiology of these agents, including larger sample sizes, the evaluation of potential transmission routes and spillover potential.
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Affiliation(s)
- Ananda Müller
- Department of Biomedical Sciences, Ross University School of Veterinary Medicine, Saint Kitts and Nevis, West Indies, Cote d'Ivoire; Instituto de Ciencias Clínicas Veterinarias, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Paulina Sepúlveda
- Instituto de Ciencias Clínicas Veterinarias, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Sophia Di Cataldo
- PhD Program in Conservation Medicine, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 252, Santiago, Chile
| | - Aitor Cevidanes
- PhD Program in Conservation Medicine, Facultad de Ciencias de la Vida, Universidad Andres Bello, República 252, Santiago, Chile
| | - Fulgencio Lisón
- Laboratorio de Ecología del Paisaje y Conservación, Departamento de Ciencias Forestales y Medioambiente, Universidad de La Frontera, P.D. Box 45-D, Temuco, Chile; Wildlife Ecology and Conservation Lab, Departamento de Zoología, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - Javier Millán
- Facultad de Ciencias de la Vida, Universidad Andres Bello, República 252, Santiago, Chile; Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Miguel Servet 177, 50013, Zaragoza, Spain; Fundación ARAID, Avda. de Ranillas, 50018, Zaragoza, Spain.
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Weitzel T, Acosta-Jamett G, Jiang J, Martínez-Valdebenito C, Farris CM, Richards AL, Abarca K. Human seroepidemiology of Rickettsia and Orientia species in Chile - A cross-sectional study in five regions. Ticks Tick Borne Dis 2020; 11:101503. [PMID: 32993924 DOI: 10.1016/j.ttbdis.2020.101503] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 05/19/2020] [Accepted: 06/30/2020] [Indexed: 01/31/2023]
Abstract
In recent years, the spectrum and epidemiology of human rickettsioses has become an emerging topic in Chile. This survey aimed to assess the seroprevalence of spotted fever group rickettsiae (SFGR), typhus group rickettsiae (TGR), and scrub typhus group orientiae (STGO) in northern, central, and southern Chile. We performed a cross-sectional study of healthy adults in rural and urban settings of five regions. Participants were chosen by double stratified random sampling in urban and by convenience in rural locations (n = 1302). Serum specimens were analyzed for group-specific IgG antibodies against SFGR, TGR, and STGO by enzyme-linked immunosorbent assays (ELISAs). Overall seroprevalences to SFGR, TGR, and STGO were 5.3 %, 1.2 %, and 0.4 %, respectively. Prevalences showed geographical differences. Statistical analyses revealed an association of older age with seropositivity to SFGR and to TGR and of rural setting and male gender with seropositivity to SFGR. The study indicates that SFGR, TGR, and STGO are endemic in Chile. The very low STGO seroprevalence might indicate an insufficient sensitivity of serological tests using Asian O. tsutsugamushi strains as ELISA antigens for the detection of antibodies against Chilean Orientia species.
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Affiliation(s)
- Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile; Instituto de Ciencias e Innovación en Medicina (ICIM) Facultad de Medicina Clínica Alemana Universidad del Desarrollo Santiago Chile.
| | - Gerardo Acosta-Jamett
- Instituto de Medicina Preventiva Veterinaria y Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.
| | - Ju Jiang
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA.
| | - Constanza Martínez-Valdebenito
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
| | - Christina M Farris
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, USA.
| | - Allen L Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences. Bethesda, MD, USA.
| | - Katia Abarca
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile.
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Weitzel T, Makepeace BL, Elliott I, Chaisiri K, Richards AL, Newton PN. Marginalized mites: Neglected vectors of neglected diseases. PLoS Negl Trop Dis 2020; 14:e0008297. [PMID: 32701946 PMCID: PMC7377360 DOI: 10.1371/journal.pntd.0008297] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
- Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Benjamin L. Makepeace
- Institute of Infection & Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Ivo Elliott
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Lao PDR
| | - Kittipong Chaisiri
- Department of Helminthology, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Allen L. Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, Maryland, United States of America
| | - Paul N. Newton
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Lao PDR
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Acosta-Jamett G, Weitzel T, López J, Alvarado D, Abarca K. Prevalence and Risk Factors of Antibodies to Anaplasma spp. in Chile: A Household-Based Cross-Sectional Study in Healthy Adults and Domestic Dogs. Vector Borne Zoonotic Dis 2020; 20:572-579. [PMID: 32233979 DOI: 10.1089/vbz.2019.2587] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: Pet-related tick-borne infections constitute an emerging problem in human and veterinary medicine worldwide. In Chile, two pathogens of the Anaplasmataceae family, Anaplasma platys and Ehrlichia canis, have been identified in recent years in dogs and vectors. This epidemiological survey aimed to determine the human and canine seroprevalence of Anaplasma spp. in urban and rural areas of different regions in Chile and to analyze the factors associated with seropositivity. Methods: We performed a cross-sectional household-based study in four regions, where healthy adults and their household dogs were included. Households were chosen by double stratified random sampling in urban areas and by convenience sampling in rural areas. Anaplasma seroreactivity was determined by a commercial microimmunofluorescence assay using Anaplasma phagocytophilum antigens. A questionnaire survey was applied to assess risk factors for Anaplasma seropositivity. Results: A total of 1105 persons and 905 dogs were included. The overall seroprevalence in humans was 9.4%, ranging from 5.6% in central Chile to 13.7% in the extreme north; in dogs the overall prevalence was 44.0% and ranged from 37.2% in the northern region to 61.1% in central Chile. Risk factors for human seropositivity were lower education and external deworming of dogs, whereas canine seropositivity was associated to urban site, mixed-breed, older animals, and tick infestation. Conclusions: This cross-sectional study suggests a broad exposure of both dogs and dog owners to Anaplasma or related agents in Chile. Further epidemiological and clinical studies are necessary to understand the complete spectrum and epidemiology of tick-borne zoonotic infections in the different ecoclimatic regions of Chile.
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Affiliation(s)
- Gerardo Acosta-Jamett
- Instituto de Medicina Preventiva Veterinaria y Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile.,Chilean Rickettsia and Zoonosis Research Group, Santiago, Chile
| | - Thomas Weitzel
- Chilean Rickettsia and Zoonosis Research Group, Santiago, Chile.,Laboratorio Clínico, Clínica Alemana, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile.,Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
| | - Javier López
- Hospital Veterinario Puente Alto, Santiago, Chile
| | - Doris Alvarado
- Instituto de Medicina Preventiva Veterinaria y Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Katia Abarca
- Chilean Rickettsia and Zoonosis Research Group, Santiago, Chile.,Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Facultad de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
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Richards AL, Jiang J. Scrub Typhus: Historic Perspective and Current Status of the Worldwide Presence of Orientia Species. Trop Med Infect Dis 2020; 5:E49. [PMID: 32244598 PMCID: PMC7344502 DOI: 10.3390/tropicalmed5020049] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2020] [Revised: 03/22/2020] [Accepted: 03/25/2020] [Indexed: 12/13/2022] Open
Abstract
Scrub typhus and its etiological agents, Orientia species, have been around for a very long time. Historical reference to the rickettsial disease scrub typhus was first described in China (313 AD) by Hong Ge in a clinical manual (Zhouhofang) and in Japan (1810 AD) when Hakuju Hashimoto described tsutsuga, a noxious harmful disease in the Niigata prefecture. Other clinicians and scientists in Indonesia, Philippines, Taiwan, Australia, Vietnam, Malaysia, and India reported on diseases most likely to have been scrub typhus in the early 1900s. All of these initial reports about scrub typhus were from an area later designated as the Tsutsugamushi Triangle-an area encompassing Pakistan to the northwest, Japan to the northeast and northern Australia to the south. It was not until the 21st century that endemic scrub typhus occurring outside of the Tsutsugamushi Triangle was considered acceptable. This report describes the early history of scrub typhus, its distribution in and outside the Tsutsugamushi Triangle, and current knowledge of the causative agents, Orientia species.
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Affiliation(s)
- Allen L. Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA
| | - Ju Jiang
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD 20817, USA;
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Acosta-Jamett G, Martínez-Valdebenito C, Beltrami E, Silva-de La Fuente MC, Jiang J, Richards AL, Weitzel T, Abarca K. Identification of trombiculid mites (Acari: Trombiculidae) on rodents from Chiloé Island and molecular evidence of infection with Orientia species. PLoS Negl Trop Dis 2020; 14:e0007619. [PMID: 31971956 PMCID: PMC6999909 DOI: 10.1371/journal.pntd.0007619] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2019] [Revised: 02/04/2020] [Accepted: 12/03/2019] [Indexed: 11/18/2022] Open
Abstract
Background Scrub typhus is an emerging vector-borne zoonosis, caused by Orientia spp. and transmitted by larvae of trombiculid mites, called chiggers. It mainly occurs within a region of the Asia-Pacific called the tsutsugamushi triangle, where rodents are known as the most relevant hosts for the trombiculid vector. However, the reservoir(s) and vector(s) of the scrub typhus outside Asia-Pacific are unknown. The disease has recently been discovered on and is considered endemic for Chiloé Island in southern Chile. The aim of the present work was to detect and determine the prevalence of chiggers on different rodent species captured in probable sites for the transmission of orientiae responsible for scrub typhus on Chiloé Island in southern Chile and to molecularly examine collected chiggers for the presence of Orientia DNA. Methodology/Principal findings During the austral summer 2018, rodents were live-trapped in six sites and examined for chigger infestation. All study sites were rural areas on Chiloé Island, previously identified as probable localities where human cases acquired the scrub typhus. During a total of 4,713 trap-nights, 244 rodents of seven species were captured: the most abundant was Abrothrix olivacea. Chiggers were detected on all seven rodent species with a 55% prevalence rate. Chiggers showed low host specificity and varied according to site specific host abundance. Three genera of trombiculids were identified. Herpetacarus was the most abundant genus (93%), prevalent in five of the six sites. Infestation rates showed site specific differences, which were statistically significant using a GLM model with binomial errors. Molecular analyses proved that 21 of 133 (15.8%) mite pools were positive for Orientia species, all of them belonged to the genus Herpetacarus. Conclusions/Significance This study firstly reports the presence of different rodent-associated chigger mites positive for Orientia sp., in a region endemic for scrub typhus in southern Chile. Herpetacarus and two other genera of mites were found with high infestation rates of rodents in sites previously identified as probable exposure of scrub typhus cases. A substantial percentage of mite pools were positive for Orientia DNA, suggesting that chigger mites serve as vectors and reservoirs of this emerging zoonosis in South America. Scrub typhus is a chigger-transmitted zoonotic infection caused by Orientia species, which is endemic to the tsutsugamushi triangle in Asia-Pacific region. Recently, a focus of scrub typhus in South America has been confirmed on Chiloé Island in southern Chile. However, the vectors of scrub typhus in this region remain unknown. We undertook a survey to study the presence of chiggers on different rodent species in areas identified as probable sites of exposure to scrub typhus on Chiloé Island. The study showed that 55% of rodents were infested by trombiculids. Three mite genera were identified, of which Herpetacarus was the most abundant. Chiggers showed low host specificity, but spatial differences. Using molecular techniques, the trombiculid mites were found to be infected with Orientia species. These findings suggest that chigger mites play a role in the life cycle and transmission of this emerging infectious disease in Chile.
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Affiliation(s)
- Gerardo Acosta-Jamett
- Instituto de Medicina Preventiva Veterinaria, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Programa de Investigación Aplicada en Fauna Silvestre, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - Constanza Martínez-Valdebenito
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Laboratorio de Infectología y Virología Molecular, Red Salud UC–Christus, Santiago, Chile
| | - Esperanza Beltrami
- Instituto de Medicina Preventiva Veterinaria, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
- Escuela de Graduados, Facultad de Ciencias Veterinarias, Universidad Austral de Chile, Valdivia, Chile
| | - María Carolina Silva-de La Fuente
- Departamento de Ciencias Animal, Facultad de Ciencias Veterinarias, Universidad de Concepción, Concepción, Chile
- Programa de Doctorado en Ciencias Veterinarias, Facultad de Ciencias Veterinarias, Universidad de Concepción, Chillán, Chile
- Facultad de Medicina Veterinaria, Universidad San Sebastián, Concepción, Chile
| | - Ju Jiang
- Viral and Rickettsial Diseases Department, Naval Medical Research Center, Silver Spring, MD, United States of America
| | - Allen L. Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, United States of America
| | - Thomas Weitzel
- Laboratorio Clínico, Clínica Alemana de Santiago, Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
- Hantavirus and Zoonoses Program, Instituto de Ciencias e Innovación en Medicina (ICIM), Facultad de Medicina Clínica Alemana, Universidad del Desarrollo, Santiago, Chile
- * E-mail: (TW); (KA)
| | - Katia Abarca
- Departamento de Enfermedades Infecciosas e Inmunología Pediátricas, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- Millennium Institute on Immunology and Immunotherapy, Escuela de Medicina, Pontificia Universidad Católica de Chile, Santiago, Chile
- * E-mail: (TW); (KA)
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Seo CW. Analysis of Factors Related to Regional Occurrence Distribution of Scrub Typhus: 2012∼2016. KOREAN JOURNAL OF CLINICAL LABORATORY SCIENCE 2019. [DOI: 10.15324/kjcls.2019.51.4.420] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Affiliation(s)
- Choong Won Seo
- Division of Control for Zoonotic and Vector Borne Disease, Korea Centers for Disease Control and Prevention, Cheongju, Korea
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Blacksell SD, Robinson MT, Newton PN, Ruanchaimun S, Salje J, Wangrangsimakul T, Wegner MD, Abdad MY, Bennett AM, Richards AL, Stenos J, Day NPJ. Biosafety and biosecurity requirements for Orientia spp. diagnosis and research: recommendations for risk-based biocontainment, work practices and the case for reclassification to risk group 2. BMC Infect Dis 2019; 19:1044. [PMID: 31822267 PMCID: PMC6902544 DOI: 10.1186/s12879-019-4653-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 11/22/2019] [Indexed: 11/22/2022] Open
Abstract
Scrub typhus is an important arthropod-borne disease causing significant acute febrile illness by infection with Orientia spp.Using a risk-based approach, this review examines current practice, the evidence base and regulatory requirements regarding matters of biosafety and biosecurity, and presents the case for reclassification from Risk Group 3 to Risk Group 2 along with recommendations for safe working practices of risk-based activities during the manipulation of Orientia spp. in the laboratory.We recommend to reclassify Orientia spp. to Risk Group 2 based on the classification for RG2 pathogens as being moderate individual risk, low community risk. We recommend that low risk activities, can be performed within a biological safety cabinet located in a Biosafety Level (BSL) 2 core laboratory using standard personal protective equipment. But when the risk assessment indicates, such as high concentration and volume, or aerosol generation, then a higher biocontainment level is warranted. For, the majority of animal activities involving Orientia spp., Animal BSL 2 (ABSL2) is recommended however where high risk activities are performed including necropsies, Animal BSL (ABSL3) is recommended.
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Affiliation(s)
- Stuart D Blacksell
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand.
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Churchill Hospital, Oxford, OX3 7FZ, UK.
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Mahosot Hospital, Vientiane, Lao People's Democratic Republic.
| | - Matthew T Robinson
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Churchill Hospital, Oxford, OX3 7FZ, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Paul N Newton
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Churchill Hospital, Oxford, OX3 7FZ, UK
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit (LOMWRU), Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Soiratchaneekorn Ruanchaimun
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Jeanne Salje
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Churchill Hospital, Oxford, OX3 7FZ, UK
| | - Tri Wangrangsimakul
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Churchill Hospital, Oxford, OX3 7FZ, UK
| | - Matthew D Wegner
- Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok, 10400, Thailand
| | - Mohammad Yazid Abdad
- Infectious Disease Research Laboratory, National Centre for Infectious Diseases, Singapore, Singapore
| | - Allan M Bennett
- Public Health England, Biosafety, Air and Water Microbiology Group, Porton, Salisbury, Wiltshire, SP4 0JG, UK
| | - Allen L Richards
- Department of Preventive Medicine and Biostatistics, Uniformed Services University of the Health Sciences, Bethesda, MD, 20814, USA
| | - John Stenos
- Australian Rickettsial Reference Laboratory, Geelong Hospital, Geelong, Victoria, 3220, Australia
| | - Nicholas P J Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Churchill Hospital, Oxford, OX3 7FZ, UK
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