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Saraswati K, Tanganuchitcharnchai A, Ongchaikupt S, Mukaka M, Day NPJ, Baird JK, Antonjaya U, Myint KSA, Dewi YP, Yudhaputri FA, Haryanto S, Witari NPD, Blacksell SD. Scrub typhus in Indonesia: A cross-sectional analysis of archived fever studies samples. Trans R Soc Trop Med Hyg 2024; 118:321-327. [PMID: 38205975 PMCID: PMC11062201 DOI: 10.1093/trstmh/trad094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 11/06/2023] [Accepted: 12/16/2023] [Indexed: 01/12/2024] Open
Abstract
BACKGROUND Scrub typhus is an understudied vector-borne bacterial infection. METHODS We tested archived fever samples for scrub typhus seropositivity to begin charting its geographic distribution in Indonesia. We analysed 1033 serum samples from three sites. IgM and IgG enzyme-linked immunosorbent assay (ELISA) against Orientia tsutsugamushi was performed using Karp, Kato, Gilliam, TA 716 antigens. To determine the cutoff in the absence of a presumed unexposed population and gold standard tests, we identified the visual inflection point, performed change point analysis, and used finite mixture models. RESULTS The optical density cutoff values used for IgM and IgG were 0.49 and 0.13, respectively. Across all sites, IgM seropositivity was 4.6% (95% CI: 3.4 to 6.0%) while IgG seropositivity was 4.4% (95% CI: 3.3 to 5.8%). The overall seropositivity across sites was 8.8% (95% CI: 8.1 to 11.7%). The overall seropositivity for Jambi, Denpasar, Tabanan were 9.7% (95% CI: 7.0 to 13.3%), 8.0% (95% CI: 5.7 to 11.0%), 9.0% (95% CI: 6.1 to 13.0%), respectively. CONCLUSIONS We conclude that O. tsutsugamushi exposure in humans occurred at all sites analysed and could be the cause of illness in some cases. Though it was not the main cause of acute fever in these locations, it is still important to consider scrub typhus in cases not responding to beta-lactam antibiotics. Future seroprevalence surveys and testing for scrub typhus in acute febrile illness studies will be essential to understand its distribution and burden in Indonesia.
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Affiliation(s)
- Kartika Saraswati
- Oxford University Clinical Research Unit Indonesia, Faculty of Medicine, Universitas Indonesia, 10430 Jakarta, Indonesia
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 10400 Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, OX3 7LG Oxford, UK
| | - Ampai Tanganuchitcharnchai
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 10400 Bangkok, Thailand
| | - Sirada Ongchaikupt
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 10400 Bangkok, Thailand
| | - Mavuto Mukaka
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 10400 Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, OX3 7LG Oxford, UK
| | - Nicholas P J Day
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 10400 Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, OX3 7LG Oxford, UK
| | - J Kevin Baird
- Oxford University Clinical Research Unit Indonesia, Faculty of Medicine, Universitas Indonesia, 10430 Jakarta, Indonesia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, OX3 7LG Oxford, UK
| | - Ungke Antonjaya
- Oxford University Clinical Research Unit Indonesia, Faculty of Medicine, Universitas Indonesia, 10430 Jakarta, Indonesia
| | | | - Yora P Dewi
- Exeins Health Initiative, 12870 Jakarta, Indonesia
| | | | - Sotianingsih Haryanto
- Raden Mattaher Hospital, 36122 Jambi, Indonesia
- Faculty of Medicine and Health Sciences, Universitas Jambi, 36361 Jambi, Indonesia
| | - N P Diah Witari
- Faculty of Medicine and Health Sciences, Warmadewa University, 80235 Denpasar, Bali, Indonesia
| | - Stuart D Blacksell
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, 10400 Bangkok, Thailand
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, OX3 7LG Oxford, UK
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Chunduru K, A R M, Poornima S, Hande H M, Devaki R, Varghese GM, Saravu K. Clinical, laboratory profile and molecular characterization of Orientia tsutsugamushi among fatal scrub typhus patients from Karnataka, India. Infect Dis (Lond) 2024; 56:220-229. [PMID: 38069822 DOI: 10.1080/23744235.2023.2290106] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Accepted: 11/27/2023] [Indexed: 02/16/2024] Open
Abstract
BACKGROUND Scrub typhus is a vector-borne infection caused by the obligate intracellular organism Orientia tsutsugamushi. In some cases, scrub typhus can result in severe complications, multiorgan failure and death. OBJECTIVE To study the clinical and laboratory profiles of patients who succumbed to scrub typhus. METHODS A prospective cohort study was conducted from August 2019 through April 2023 on scrub typhus patients admitted to our hospital. Clinical and laboratory parameters of all the patients were recorded, and blood samples were drawn. To confirm scrub typhus, a nested polymerase chain reaction (nPCR) was performed in collected samples. Viable amplicons were sequenced, and phylogenetic analyses were performed to identify infecting genotypes. RESULTS A total of 261 patients were enrolled. Of these, nine (3.45%) patients succumbed at a median (Interquartile Range) duration of 5 (1.5, 10.5) days after admission. Sepsis with septic shock (9, 100%) and acute kidney injury (AKI) (6, 66%) were noted among the succumbed patients. All the succumbed patients (100%) required intensive care admission, inotropic and ventilatory support. While 5 (55%) patients required dialysis, two (22%) required blood transfusion. Three (33%) patient samples were co-positive for Leptospira IgM, and four (44%) patients had superinfection with Candida tropicalis, multi-drug-resistant (MDR) E. Coli sepsis, pan drug-resistant (PDR) Acinetobacter Baumanii, and Klebsiella pneumoniae. Phylogenetic analysis revealed Orientia tsutsugamushi Japanese Gilliam-variant (JG-v) like (50%), Karp-like (37.5%), and Japanese Gilliam (JG) like (12.5%) strains among succumbed patients. CONCLUSION Delay in scrub typhus diagnosis can result in severe complications, septic shock, and multisystem organ failure, culminating in death.
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Affiliation(s)
- Kiran Chunduru
- Department of Infectious Diseases, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Manoj A R
- Department of Infectious Diseases, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Subhadra Poornima
- Department of Genetics and Molecular Medicine, Kamineni Life Sciences, Hyderabad, Telangana, India
| | - Manjunatha Hande H
- Department of Medicine, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
| | - Ramakrishna Devaki
- Department of Biochemistry, Kamineni Academy of Medical Sciences and Research Centre, LB Nagar, Hyderabad, Telangana, India
| | - George M Varghese
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Kavitha Saravu
- Department of Infectious Diseases, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Manipal, Karnataka, India
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Chankate P, Kalambaheti T, Kosoltanapiwat N, Tanganuchitcharnchai A, Blacksell SD, Chantratita N, Leaungwutiwong P. A Use of 56-kDa Recombinant Protein of Orientia tsutsugamushi Karp Serotype in Serodiagnosis of Scrub Typhus by Enzyme-Linked Immunosorbent Assay in Thais. Trop Med Infect Dis 2022; 8:10. [PMID: 36668917 PMCID: PMC9865064 DOI: 10.3390/tropicalmed8010010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 12/02/2022] [Accepted: 12/21/2022] [Indexed: 12/28/2022] Open
Abstract
Scrub typhus is a mite-borne disease caused by a Gram-negative obligately intracellular bacillus, Orientia tsutsugamushi. The disease is endemic in the Asia-Australia-Pacific region, including Thailand. Scrub typhus generally manifests as acute undifferentiated febrile fever along with myalgia, rash, and lymphadenopathy. An eschar can be a valuable diagnostic clue, but this skin lesion may be missed in some patients. The disease symptoms resemble those of other febrile illnesses such as leptospirosis, typhoid, murine typhus, malaria, and dengue fever, making a laboratory diagnosis necessary for the definitive diagnosis. In this study, we expressed a recombinant protein derived from 56-kDa type-specific antigen of O. tsutsugamushi Karp serotype and tested its ability to detect and differentiate scrub typhus infection. IgM and IgG antibodies were determined in sera from scrub typhus (n = 92) and other febrile illness patients (murine typhus (n = 25), melioidosis (n = 36), leptospirosis (n = 42), and dengue (n = 35)) from Thailand. Sensitivities of 87.0% and 59.8% with a specified assay cut-off were obtained for IgM and IgG indirect ELISAs, respectively, with a specificity of 100% in both tests. The sensitivity was increased to 95.7% when a combination of IgM and IgG ELISAs results was considered. Our study suggested a potential of the 56-kDa recombinant protein for further development and evaluation for use in scrub typhus serodiagnosis.
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Affiliation(s)
- Phanita Chankate
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Thareerat Kalambaheti
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Nathamon Kosoltanapiwat
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Ampai Tanganuchitcharnchai
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Stuart D. Blacksell
- Mahidol-Oxford Tropical Medicine Research Unit (MORU), Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
- Centre for Tropical Medicine & Global Health, Nuffield Department of Medicine, University of Oxford, Oxford OX3 7LG, UK
| | - Narisara Chantratita
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
| | - Pornsawan Leaungwutiwong
- Department of Microbiology and Immunology, Faculty of Tropical Medicine, Mahidol University, Bangkok 10400, Thailand
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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Rathnasekara T, Wijekoon L, Senanayake H, Siribaddana S. Rapid Recovery of Acute Respiratory Distress Syndrome in Scrub Typhus, With Pulse Methylprednisolone and Therapeutic Plasma Exchange. Cureus 2022; 14:e30329. [PMID: 36407237 PMCID: PMC9662697 DOI: 10.7759/cureus.30329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/15/2022] [Indexed: 06/16/2023] Open
Abstract
Acute respiratory distress syndrome (ARDS) is an atypical presentation of scrub typhus infection with associated high morbidity and mortality compared to uncomplicated scrub typhus infection. Here we report an otherwise healthy 41-year-old female patient admitted with moderate ARDS secondary to scrub typhus infection who gained comparatively rapid recovery within 72 hours following intravenous methylprednisolone pulse (MPP) therapy with therapeutic plasma exchange (TPE), suggesting a beneficial role of MPP and TPE in the treatment of ARDS secondary to scrub typhus infection. To our knowledge, this is the first case report regarding the use of MPP therapy and TPE in a patient with ARDS due to scrub typhus infection.
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Affiliation(s)
- Thilina Rathnasekara
- Internal Medicine, Postgraduate Institute of Medicine, University of Colombo, Colombo, LKA
| | - Lanka Wijekoon
- Medicine, Faculty of Medicine, University of Rajarata, Anuradhapura, LKA
| | - Hemal Senanayake
- Medicine, Faculty of Medicine, University of Rajarata, Anuradhapura, LKA
| | - Sisira Siribaddana
- Medicine, Faculty of Medicine, University of Rajarata, Anuradhapura, LKA
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Tarai B, Sen P, Kanaujia R, Kaur J, Biswal M, Das P. Epidemiological, clinical and genetic characterization of scrub typhus in patients presenting with acute febrile illness in New Delhi. Indian J Med Microbiol 2022; 40:552-556. [PMID: 35953350 DOI: 10.1016/j.ijmmb.2022.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 07/12/2022] [Accepted: 07/16/2022] [Indexed: 11/17/2022]
Abstract
PURPOSE Scrub typhus (ST) is a zoonotic disease, caused by O. tsutsugamushi is a major cause of acute febrile illness (AFI) in India. There is a need to study the prevalence and risk factors in various regions of India. METHODS A study to estimate the prevalence and study the risk factors of ST in patients presenting with acute febrile illness (AFI) was performed. All patients underwent serology for IgM antibodies to Orientia tsutsugamushi (In Bios International Inc, Seattle, WA) as per the manufacturers' protocol. Following this, Polymerase Chain reaction (PCR) (real time SYBR green based targeting groEL gene and conventional PCR targeting 56 kDa type specific antigen gene) was performed from stored serum samples. RESULTS During the study period, 473 patients were admitted. Of these 56 (11.8%) patients were ST positive by IgM serology. The conventional PCR targeting 56 kDa type specific antigen gene of O. tsutsugamushi was positive in six patients while Ot groEL SYBR green based PCR) was positive in five. PCR was positive in patients who had demonstrated a higher OD value in ELISA. Conventional PCR positive amplicons were sent for Sanger sequencing and confirmed to be O. tsutsugamushi. The mean age of the patients was 49 ± 18.3 years and males constituted a higher number of patients (67.9%, n = 38). The pathognomonic eschar was present in 7 (12.5%) patients. Phylogenetic analysis revealed that sequences clustered close to Kato-like Hualein-20 strain and Karp-like Linh DT strains. All patients were administered doxycycline in our study. Mortality was recorded in 8.9% of the patients. CONCLUSIONS In patients presenting with acute febrile illness, ST should be considered as a differential diagnosis, especially in post-monsoon season. Along with serology, serum can also be used as sample for PCR in an intracellular bacterium like O. tsutsugamushi.
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Devamani CS, Prakash JA, Alexander N, Stenos J, Schmidt WP. The Incidence of Orientia Tsutsugamushi Infection in Rural South India. Epidemiol Infect 2022;:1-24. [PMID: 35765168 DOI: 10.1017/S0950268822001170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Scrub typhus is a common bacterial infection in Asia caused by Orientia tsutsugamushi. This serological cohort study estimated the incidence of infection in a rural population in South India. Participants were enrolled through systematic sampling in 46 villages at baseline, and revisited the following year. Blood samples were tested for IgG antibodies using ELISA, followed by indirect immunofluorescence assays (IFA) in those positive for ELISA at both rounds. A case was defined as sero-conversion (ELISA), or at least a 4-fold titre increase (IFA), between the two time points. In addition to crude incidence rate estimates, we used piecewise linear rates across calendar months, with rates proportional to the monthly incidence of local hospital cases to address seasonality and unequal follow-up times. Of 402 participants, 61.7% were female. The mean age was 46.7 years, (range 13–88). 21 participants showed evidence for serological infection. The estimated incidence was 4.4 per 100 person-years (95% CI 2.8–6.7). The piecewise linear rates approach resulted in a similar estimate of 4.6 per 100 person years (95% CI 2.9–6.9). Considering previous estimates of symptomatic scrub typhus incidence in the same study population, only about 2–5% of infections may result in clinically relevant disease.
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Liao CC, Tsai CH, Lo HR, Lin PR, Lin CC, Chao YC. Development of a Scrub Typhus Diagnostic Platform Incorporating Cell-Surface Display Technology. Front Immunol 2021; 12:761136. [PMID: 34707621 PMCID: PMC8542878 DOI: 10.3389/fimmu.2021.761136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/23/2021] [Indexed: 11/13/2022] Open
Abstract
Scrub typhus (ST), also known as tsutsugamushi disease and caused by rickettsia Orientia tsutsugamushi, is an underestimated fatal epidemic in the Asia-Pacific region, resulting in a million human infections each year. ST is easily misdiagnosed as clinical diagnosis is based on non-specific skin eschar and flu-like symptoms. Thus, the lack of accurate, convenient, and low-cost detection methods for ST poses a global health threat. To address this problem, we adopted baculovirus surface-display technology to express three variants of TSA56, the major membrane antigen of O. tsutsugamushi, as well as the passenger domain of ScaC (ScaC-PD), on insect Sf21 cell surfaces rather than biosafety level 3 bacteria in an enzyme-linked immunosorbent assay (ELISA). Recombinant TSA56 and ScaC-PD were all properly expressed and displayed on Sf21 cells. Our cell-based ELISA comprising the four antigen-displaying cell types interacted with monoclonal antibodies as well as serum samples from ST-positive field-caught rats. This cell-based ELISA presented high accuracy (96.3%), sensitivity (98.6%), and specificity (84.6%) when tested against the ST-positive rat sera. Results of a pilot study using human sera were also highly consistent with the results of immunofluorescence analyses. By adopting this approach, we circumvented complex purification and refolding processes required to generate recombinant O. tsutsugamushi antigens and reduced the need for expensive equipment and extensively trained operators. Thus, our system has the potential to become a widely used serological platform for diagnosing ST.
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Affiliation(s)
- Chih-Chi Liao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Chih-Hsuan Tsai
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Huei-Ru Lo
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan
| | - Pey-Ru Lin
- Institute of Preventive Medicine, National Defense Medical Center, Taipei, Taiwan
| | - Chang-Chi Lin
- Institute of Preventive Medicine, National Defense Medical Center, Taipei, Taiwan
| | - Yu-Chan Chao
- Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.,Department of Entomology, National Chung Hsing University, Taichung, Taiwan.,Department of Entomology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan.,Department of Plant Pathology and Microbiology, College of Bioresources and Agriculture, National Taiwan University, Taipei, Taiwan
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9
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Basu A, Chowdhoury SR, Sarkar M, Khemka A, Mondal R, Datta K, Mondal K. Scrub Typhus-Associated Hemophagocytic Lymphohistiocytosis: Not a Rare Entity in Pediatric Age Group. J Trop Pediatr 2021; 67:6129646. [PMID: 33547467 DOI: 10.1093/tropej/fmab001] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
BACKGROUND Our goal was to study the demographic, clinical and laboratory profile and outcome of scrub typhus-associated hemophagocytic lymphohistiocytosis (HLH) in the pediatric age group. METHODS We conducted a prospective observational study in a tertiary care teaching hospital over a period of 1 year. Children in the age group of 1 month to 12 years with IgM ELISA positive for scrub typhus were included in the study. HLH was diagnosed using HLH-2004 criteria. Demographic, clinical and laboratory profile, treatment and outcome of HLH patients were noted and also compared with non-HLH scrub typhus patients. RESULTS Among 58 children with scrub typhus infection, 18 had HLH. The mean age of patients with HLH was 35.3 ± 44.8 months and 61% were male. Anemia, thrombocytopenia and hyperferritinemia were seen in all the patients. Hypertriglyceridemia, hypofibrinogenemia and coagulopathy were noted in 78%, 56% and 44%, respectively. All the patients were treated with intravenous doxycycline for an average duration of 9.5 days. Intravenous immunoglobulin and methylprednisolone were given in 33% and 22% cases, respectively. Complications like acute respiratory distress syndrome (ARDS) (p = 0.001) and MODS (p = 0.004) were significantly high in the HLH group. Younger age (<3 years), fever > 7 days, presence of convulsion, ARDS and MODS were the clinical predictors of scrub typhus-associated HLH. CONCLUSION HLH in scrub typhus infected children is being increasingly recognized. Younger age, prolonged fever, presence of convulsion, ARDS and MODS should alert clinicians of the risk of HLH. Treating the primary cause usually cures the disease and immunomodulator therapy need not be routinely administered.
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Affiliation(s)
- Ankika Basu
- Department of Pediatrics, Medical College and Hospital, Kolkata, West Bengal 700073, India
| | | | - Mihir Sarkar
- Department of Pediatrics, Medical College and Hospital, Kolkata, West Bengal 700073, India
| | - Arpita Khemka
- Department of Pediatrics, Medical College and Hospital, Kolkata, West Bengal 700073, India
| | - Rakesh Mondal
- Department of Pediatrics, Medical College and Hospital, Kolkata, West Bengal 700073, India
| | - Kalpana Datta
- Department of Pediatrics, Medical College and Hospital, Kolkata, West Bengal 700073, India
| | - Kalyanbrata Mondal
- Department of Pediatrics, Medical College and Hospital, Kolkata, West Bengal 700073, India
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Elders PND, Swe MMM, Phyo AP, McLean ARD, Lin HN, Soe K, Htay WYA, Tanganuchitcharnchai A, Hla TK, Tun NN, Nwe TT, Moe MM, Thein WM, Zaw NN, Kyaw WM, Linn H, Htwe YY, Smithuis FM, Blacksell SD, Ashley EA. Serological evidence indicates widespread distribution of rickettsioses in Myanmar. Int J Infect Dis 2020; 103:494-501. [PMID: 33310022 PMCID: PMC7862081 DOI: 10.1016/j.ijid.2020.12.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 12/04/2020] [Accepted: 12/07/2020] [Indexed: 11/26/2022] Open
Abstract
Diagnosis of rickettsial infections is difficult in low-resource settings; this leads to delays in receiving appropriate treatment. Before this study, the distribution of rickettsioses in Myanmar was not known. This serosurvey shows that rickettsioses are widespread in Myanmar. Particularly high prevalence of scrub typhus was found in central and northern regions.
Background Little research has been published on the prevalence of rickettsial infections in Myanmar. This study determined the seroprevalence of immunoglobulin G (IgG) antibodies to rickettsial species in different regions of Myanmar. Methods Seven hundred leftover blood samples from patients of all ages in primary care clinics and hospitals in seven regions of Myanmar were collected. Samples were screened for scrub typhus group (STG), typhus group (TG) and spotted fever group (SFG) IgG antibodies using enzyme-linked immunosorbent assays (ELISA). Immunofluorescence assays were performed for the same rickettsial groups to confirm seropositivity if ELISA optical density ≥0.5. Results Overall IgG seroprevalence was 19% [95% confidence interval (CI) 16–22%] for STG, 5% (95% CI 3–7%) for TG and 3% (95% CI: 2–5%) for SFG. The seroprevalence of STG was particularly high in northern and central Myanmar (59% and 19–33%, respectively). Increasing age was associated with higher odds of STG and TG seropositivity [per 10-year increase, adjusted odds ratio estimate 1.68 (p < 0.01) and 1.24 (p = 0.03), respectively]. Conclusion Rickettsial infections are widespread in Myanmar, with particularly high seroprevalence of STG IgG antibodies in central and northern regions. Healthcare workers should consider rickettsial infections as common causes of fever in Myanmar.
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Affiliation(s)
| | | | | | - Alistair R D McLean
- Myanmar Oxford Clinical Research Unit, Yangon, Myanmar; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | | | - Kyaw Soe
- Myanmar Oxford Clinical Research Unit, Yangon, Myanmar
| | | | - Ampai Tanganuchitcharnchai
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Thel K Hla
- Myanmar Oxford Clinical Research Unit, Yangon, Myanmar; Medical Action Myanmar, Yangon, Myanmar
| | - Ni Ni Tun
- Medical Action Myanmar, Yangon, Myanmar
| | - Thin Thin Nwe
- Magway General Hospital and University of Medicine, Magway, Myanmar; University of Medicine 2, Yangon, Myanmar
| | - Myat Myat Moe
- Magway General Hospital and University of Medicine, Magway, Myanmar
| | - Win May Thein
- Mandalay General Hospital and University of Medicine, Mandalay, Myanmar
| | - Ni Ni Zaw
- Mandalay General Hospital and University of Medicine, Mandalay, Myanmar
| | | | - Htun Linn
- Monywa General Hospital, Monywa, Myanmar
| | | | - Frank M Smithuis
- Myanmar Oxford Clinical Research Unit, Yangon, Myanmar; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom; Medical Action Myanmar, Yangon, Myanmar
| | - Stuart D Blacksell
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom; Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | - Elizabeth A Ashley
- Myanmar Oxford Clinical Research Unit, Yangon, Myanmar; 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, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao Democratic People's Republic.
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11
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Elders PND, Dhawan S, Tanganuchitcharnchai A, Phommasone K, Chansamouth V, Day NPJ, Garcia-Rivera JA, Hertz JC, Mayxay M, Vongsouvath M, Dubot-Pérès A, Robinson MT, Newton PN, Blacksell SD. Diagnostic accuracy of an in-house Scrub Typhus enzyme linked immunoassay for the detection of IgM and IgG antibodies in Laos. PLoS Negl Trop Dis 2020; 14:e0008858. [PMID: 33284807 DOI: 10.1371/journal.pntd.0008858] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2020] [Revised: 12/17/2020] [Accepted: 10/06/2020] [Indexed: 01/30/2023] Open
Abstract
Scrub typhus is a major cause of morbidity and mortality in Southeast Asia. Diagnosis of scrub typhus is difficult due to a lack of accessible validated diagnostic tools. Despite its objectivity, the diagnostic accuracy of ELISA tests is influenced by methodological and patient factors. This study aims to evaluate the performance of a novel in-house ELISA developed in the Mahidol Oxford Tropical Medicine Research Unit (MORU) for anti-scrub typhus group IgM and IgG compared to the “gold standard” reference IFA and PCR, and to determine whether the in-house ELISA can be used as a seroepidemiological screening tool and/or stand-alone test for scrub typhus. A total of 1,976 admission and 1,438 participant follow-up sera collected in the Lao PDR (Laos) were tested with ELISA for IgM and IgG. Samples with an ELISA OD≥0.50 were tested with IFA for IgM and/or IgG. A strong positive relationship was present between ELISA ODs and IFA titers for admission IgM (r2: 0.70, p <0.005) and IgG (r2: 0.76, p<0.005), and for follow-up IgM and IgG (both r2: 0.76, p<0.005) samples. The best compromise between sensitivity and specificity for the ELISA OD cut-off is likely to be between 0.8–1.0 for IgM antibodies and 1.2–1.8 for IgG antibodies. These results demonstrate that the diagnostic accuracy of the MORU in-house scrub typhus group ELISA is comparable to that of IFA, with similar results as reported for the commonly used InBios Scrub Typhus Detect ELISA, validating the use of the in-house ELISA. The optimal ELISA cut-off would depend on the use of the test, and the desired sensitivity and specificity. Further studies are required to authenticate the use of these cut-offs in other endemic regions. This in-house ELISA has the potential to replace the imperfect IFA, which could ultimately reduce the burden of scrub typhus by improving the rate of scrub typhus diagnoses in endemic low-resource areas. Scrub typhus is a mite-borne infectious disease, caused by the Orientia tsutsugamushi bacterium, resulting in considerable morbidity and mortality in the Asia-Pacific region. Diagnosis is difficult since it does not present with any distinctive clinical signs compared to other febrile illnesses in this region, except for a necrotic skin lesion (eschar) in some patients. Laboratory tests are therefore crucial to identify scrub typhus. Reliable laboratory tests need significant infrastructure and experienced staff, making access to accurate tests very limited in the low-resource endemic regions. This study aimed to evaluate the accuracy of less expensive and easier-to-use in-house Enzyme Linked Immunoassays (ELISAs) detecting immunoglobulin IgM and IgG antibodies against scrub typhus infection compared to the “gold-standard” Immunofluorescence Assays (IFAs). There was a strong positive relationship between ELISA and IFA antibody levels for both IgM and IgG. If the ELISA would be used as a stand-alone test for scrub typhus diagnosis in Laos, an ideal balance between sensitivity and specificity would likely be around an ELISA optical density (OD) of 0.8–1.0 for IgM and 1.2–1.8 for IgG. There is a need to investigate the use of these cut-offs in other endemic regions, which could improve the rate of scrub typhus diagnosis in low-resource settings.
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12
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Kannan K, John R, Kundu D, Dayanand D, Abhilash KPP, Mathuram AJ, Zachariah A, Sathyendra S, Hansdak SG, Abraham OC, Gunasekaran K, Iyadurai R, Abraham AM, Prakash JAJ, Yesudhason BL, Veeraraghavan B, Kavitha ML, Jose LR, Sumana MN, Saravu K, Varghese GM. Performance of molecular and serologic tests for the diagnosis of scrub typhus. PLoS Negl Trop Dis 2020; 14:e0008747. [PMID: 33180784 PMCID: PMC7660479 DOI: 10.1371/journal.pntd.0008747] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 08/25/2020] [Indexed: 01/19/2023] Open
Abstract
Diagnosis of scrub typhus, caused by the bacterium Orientia tsutsugamushi, is challenging because of the overlap of its non-specific symptoms with other infections coupled with the lack of sufficient data on the performance of diagnostic tests. Early diagnosis of scrub typhus is crucial to improve outcomes and this study evaluates the diagnostic performance of various tests. The present study aims at assessing the accuracy of various rapid diagnostic tests, serologic tests, and nucleic acid amplification methods on well-characterized patient samples. Adult patients with acute febrile illness and manifestations suggestive of scrub typhus confirmed by positive PCR in the blood, eschar or tissue were characterized as cases. Patients with acute febrile illness and a confirmed alternate etiology such as culture-confirmed typhoid, smear/PCR positive for malaria, PCR/NS1 antigen positive for dengue, PCR positive for influenza, PCR/MAT positive for leptospirosis, PCR positive for spotted fever were characterized as controls with other infections. The healthy controls consisted of subjects from the same geographic region. We performed the following tests on blood samples for scrub typhus and calculated the sensitivity, specificity, positive predictive value, and negative predictive value: (1) Quantitative real time PCR using 47kDa gene (qPCR); (2) Conventional PCR using 56kDa gene (cPCR); (3) Loop-mediated isothermal amplification assay (LAMP assay); (4) Immunofluorescence assay (IFA); (5) Enzyme-linked immunosorbent assay (ELISA); (6) Weil-Felix test(WF test); and (7) Immunochromatographic Rapid Diagnostic Test (RDT).Among the 316 participants, 158 had confirmed scrub typhus (cases) and 158 were controls. ELISA and RDT detecting Orientia tsutsugamushi specific IgM antibodies had excellent discriminative potential with sensitivities and specificities of 92%, 94% and 92%, 92% respectively. The sensitivity and specificity of IFA were found to be 95% and 74% respectively. IgM serology had a false positivity rate of 8% with other acute febrile illnesses such as dengue, leptospirosis and spotted fever due to the nonspecific binding of the pentavalent IgM. LAMP assay had 91.7% sensitivity and 77.2% specificity while qPCR provided excellent sensitivity (97%) and perfect specificity. In conclusion, ELISA and RDT detecting Orientia tsutsugamushi specific IgM antibodies have excellent sensitivity and specificity while the accuracy of IFA is suboptimal for the diagnosis of scrub typhus. Given its perfect specificity and superior sensitivity, qPCR is preferred for diagnostic confirmation in reference laboratories particularly for diagnosis of early disease with less than 7 days duration. This study provides a comprehensive evaluation of all currently available diagnostic tests for scrub typhus.
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Affiliation(s)
- Kavitha Kannan
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Rebecca John
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Debasree Kundu
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | - Divya Dayanand
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
| | | | - Alice Joan Mathuram
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Anand Zachariah
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Sowmya Sathyendra
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Samuel G. Hansdak
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - O. C. Abraham
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Karthik Gunasekaran
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Ramya Iyadurai
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Asha M. Abraham
- Department of Clinical Virology, Christian Medical College, Vellore, Tamil Nadu, India
| | | | | | - Balaji Veeraraghavan
- Department of Microbiology, Christian Medical College, Vellore, Tamil Nadu, India
| | - M. L. Kavitha
- Department of Haematology, Christian Medical College, Vellore, Tamil Nadu, India
| | | | | | - Kavitha Saravu
- Department of Infectious Diseases, Kasturba Medical College, Manipal, Manipal Academy of Higher Education, Karnataka, India
| | - George M. Varghese
- Department of Infectious Diseases, Christian Medical College, Vellore, Tamil Nadu, India
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13
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Suhandynata RT, Hoffman MA, Kelner MJ, McLawhon RW, Reed SL, Fitzgerald RL. Longitudinal Monitoring of SARS-CoV-2 IgM and IgG Seropositivity to Detect COVID-19. J Appl Lab Med 2020; 5:908-920. [PMID: 32428207 PMCID: PMC7313967 DOI: 10.1093/jalm/jfaa079] [Citation(s) in RCA: 82] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Accepted: 05/11/2020] [Indexed: 12/19/2022]
Abstract
Background Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a novel beta-coronavirus that has recently emerged as the cause of the 2019 coronavirus pandemic (COVID-19). Polymerase chain reaction (PCR) based tests are optimal and recommended for the diagnosis of an acute SARS-CoV-2 infection. Serology tests for viral antibodies provide an important tool to diagnose previous exposure to the virus. Here we evaluate the analytical performance parameters of the Diazyme SARS-CoV-2 IgM/IgG serology assays and describe the kinetics of IgM and IgG seroconversion observed in patients with PCR confirmed COVID-19 who were admitted to our hospital. Methods We validated the performance of the Diazyme assay in 235 subjects to determine specificity. Subsequently, we evaluated the SARS-CoV-2 IgM and IgG seroconversion of 54 PCR confirmed COVID-19 patients and determined sensitivity of the assay at three different timeframes. Result Sensitivity and specificity for detecting seropositivity at ≥ 15 days following a positive SARS-CoV-2 PCR result, was 100.0% and 98.7% when assaying for the panel of IgM and IgG. The median time to seropositivity observed for a reactive IgM and IgG result from the date of a positive PCR was 5 days (IQR: 2.75-9 days) and 4 days (IQR: 2.75-6.75 days), respectively. Conclusions Our data demonstrates that the Diazyme IgM/IgG assays are suited for the purpose of detecting SARS-CoV-2 IgG and IgM in patients with suspected SARS-CoV-2 infections. For the first time, we report longitudinal data showing the evolution of seroconversion for both IgG and IgM in a cohort of acutely ill patients in the United States. We also demonstrate a low false positive rate in patients who were presumed to be disease free.
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Affiliation(s)
| | | | | | | | - Sharon L Reed
- Department of Pathology UC, San Diego Health, San Diego, CA
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14
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Ricci D, Brancatella A, Marinò M, Rotondi M, Chiovato L, Vitti P, Latrofa F. The Detection of Serum IgMs to Thyroglobulin in Subacute Thyroiditis Suggests a Protective Role of IgMs in Thyroid Autoimmunity. J Clin Endocrinol Metab 2020; 105:5717681. [PMID: 31996918 DOI: 10.1210/clinem/dgaa038] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2019] [Accepted: 01/27/2020] [Indexed: 12/27/2022]
Abstract
CONTEXT The role of serum immunoglobulin (Ig)Ms in autoimmune thyroid diseases is uncertain. OBJECTIVE We looked for IgMs to thyroglobulin (Tg) in patients with subacute thyroiditis (SAT), which is characterized by high serum Tg levels, the possible de novo appearance of IgGs to Tg (TgAb-IgGs), and no autoimmune sequelae. MAIN OUTCOME MEASURES TgAb-IgMs and TgAb-IgGs were detected by binding to Tg using the enzyme-linked immunosorbent assay (ELISA). The upper reference limit of TgAb-IgMs and TgAb-IgGs was established in 40 normal subjects. We looked for TgAb-IgMs in 16 patients with SAT, 11 with Hashimoto's thyroiditis (HT), and 8 with Graves' disease (GD) who were all positive for TgAb-IgGs. IgM binding to bovine serum albumin (BSA), keyhole limpet hemocyanin (KLH), and glucagon in ELISA was measured. Inhibition of TgAb-IgMs binding to coated Tg was evaluated by preincubating serum samples or IgG-depleted samples with soluble Tg. RESULTS TgAb-IgMs were positive in 10/16 patients with SAT, 2/11 with HT, and 1/8 with GD. TgAb-IgMs were higher in SAT (0.95; 0.42-1.13) (median; 25th-75th percentiles) than in HT (0.47; 0.45-0.51) and GD patients (0.35; 0.33-0.40) (P < .005 for both). IgM binding of SAT sera to BSA, KLH, and glucagon was significantly lower than Tg. Preincubation with soluble Tg reduced the binding of IgMs to coated Tg by 18.2% for serum samples and by 35.0% and 42.1% for 2 IgG-depleted samples. TgAb-IgM levels were inversely, although nonsignificantly, correlated with Tg concentrations. CONCLUSIONS Tg leak associated with thyroid injury induces the production of specific TgAb-IgMs, which, in turn, increases the clearance of Tg and might prevent the establishment of a persistent thyroid autoimmune response.
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Affiliation(s)
- Debora Ricci
- Endocrinology Unit I, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Italy
| | - Alessandro Brancatella
- Endocrinology Unit I, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Italy
| | - Michele Marinò
- Endocrinology Unit I, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Italy
| | - Mario Rotondi
- Unit of Internal Medicine and Endocrinology, Fondazione Salvatore Maugeri, University of Pavia, Italy
| | - Luca Chiovato
- Unit of Internal Medicine and Endocrinology, Fondazione Salvatore Maugeri, University of Pavia, Italy
| | - Paolo Vitti
- Endocrinology Unit I, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Italy
| | - Francesco Latrofa
- Endocrinology Unit I, Department of Clinical and Experimental Medicine, University Hospital of Pisa, Italy
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Devamani CS, Schmidt WP, Ariyoshi K, Anitha A, Kalaimani S, Prakash JAJ. Risk Factors for Scrub Typhus, Murine Typhus, and Spotted Fever Seropositivity in Urban Areas, Rural Plains, and Peri-Forest Hill Villages in South India: A Cross-Sectional Study. Am J Trop Med Hyg 2020; 103:238-248. [PMID: 32458785 PMCID: PMC7356468 DOI: 10.4269/ajtmh.19-0642] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Scrub typhus and spotted fever group rickettsioses are thought to be common causes of febrile illness in India, whereas they rarely test for murine typhus. This cross-sectional study explored the risk factors associated with scrub typhus, tick-borne spotted fever, and murine typhus seropositivity in three different geographical settings, urban, rural, and hill villages in Tamil Nadu, South India. We enrolled 1,353 participants living in 48 clusters. The study included a questionnaire survey and blood sampling. Blood was tested for Orientia tsutsugamushi (scrub typhus), Rickettsia typhi (murine typhus), and spotted fever group Rickettsia IgG using ELISA. The seroprevalence of scrub typhus, spotted fever, and murine typhus were 20.4%, 10.4%, and 5.4%, respectively. Scrub typhus had the highest prevalence in rural areas (28.1%), and spotted fever was most common in peri-forested areas (14.9%). Murine typhus was more common in rural (8.7%) than urban areas (5.4%) and absent in peri-forested hill areas. Agricultural workers had a higher relative risk for scrub typhus, especially in urban areas. For murine typhus, proximity to a waterbody and owning a dog were found to be major risk factors. The main risk factors for spotted fever were agricultural work and living in proximity to a forest. Urban, rural plains, and hill settings display distinct epidemiological pattern of Orientia and rickettsial infections. Although scrub typhus and spotted fever were associated with known risk factors in this study, the findings suggest a different ecology of murine typhus transmission compared with other studies conducted in Asia.
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Affiliation(s)
| | - Wolf-Peter Schmidt
- Department for Disease Control, London School of Hygiene and Tropical Medicine, London, United Kingdom
| | - Koya Ariyoshi
- Department of Clinical Medicine, Institute of Tropical Medicine, Nagasaki University, Nagasaki, Japan
| | - Arumugam Anitha
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
| | - Saravanan Kalaimani
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
| | - John A J Prakash
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
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Anitharaj V, Stephen S, Pratheesh P. Scrub typhus in Puducherry, India: Application of nested PCR targeting three different genes - 56 kDa, 47 kDa and groEL of Orientia tsutsugamushi and comparison with ST IgM ELISA. J Vector Borne Dis 2020; 57:147-152. [PMID: 34290159 DOI: 10.4103/0972-9062.310866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND & OBJECTIVES Scrub typhus (ST), an important zoonosis caused by Orientia tsutsugamushi, is now prevalent throughout India. While demonstration of IgM antibody by Indirect Immunofluorescence Assay (IFA) is the gold standard serological test, IgM ELISA is an alternative. Demonstration of O. tsutsugamushi DNA in the blood or eschar confirms infection in the early febrile period. METHODS Scrub typhus nested PCR (n-PCR) for 56 kDa, 47 kDa and groEL genes and ST IgM ELISA were performed for 210 clinically suspected ST patients. As healthy controls, 70 voluntary blood donors were included. Statistical analysis was performed for laboratory parameters using Fisher exact test/chi-square test. Ninety-five PCR products of n-PCR positive samples were purified and submitted for gene sequencing. RESULTS PCR was positive for one or more gene targets in 75.71% of IgM ELISA positive patients and 10% of antibody negative patients. All voluntary blood donors were negative for both antibodies and DNA. Gene sequences of 95 n-PCR positive products confirmed the presence of Orientia tsutsugamushi DNA in the samples and NCBI database accession numbers MG601875 to MG601969 were obtained. INTERPRETATION & CONCLUSION Compared to IgM ELISA, sensitivity of three PCRs was 30, 51.43 and 61.43% for 56 kDa, 47 kDa and groEL targets, respectively. Since IgM ELISA positivity can persist up to one year, PCR confirms ST diagnosis in the acute phase of the illness, in the presence of IgM and even before IgM appears. Inclusion of all three genes - 56 kDa, 47 kDa and groEL, instead of a single 56 kDa target, identifies and confirms maximum number of ST patients.
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Affiliation(s)
- Velmurugan Anitharaj
- Department of Microbiology, Mahatma Gandhi Medical College & Research Institute, Sri Balaji Vidyapeeth, Puducherry, India
| | - Selvaraj Stephen
- Department of Microbiology, Mahatma Gandhi Medical College & Research Institute, Sri Balaji Vidyapeeth, Puducherry, India
| | - Pooja Pratheesh
- Department of Genomics and Proteomics, Central Interdisciplinary Research Facility, Mahatma Gandhi Medical College and Research Institute, Puducherry - 607 403, India
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17
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Kamble S, Mane A, Sane S, Sonavale S, Vidhate P, Singh MK, Gangakhedkar R, Gupte M. Seroprevalence & seroincidence of Orientia tsutsugamushi infection in Gorakhpur, Uttar Pradesh, India: A community-based serosurvey during lean (April-May) & epidemic (October-November) periods for acute encephalitis syndrome. Indian J Med Res 2020; 151:350-360. [PMID: 32461399 PMCID: PMC7371060 DOI: 10.4103/ijmr.ijmr_1330_18] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Indexed: 01/31/2023] Open
Abstract
Background & objectives In India, acute encephalitis syndrome (AES) cases are frequently reported from Gorakhpur district in Uttar Pradesh. Scrub typhus is one of the predominant aetiological agents for these cases. In order to delineate the extent of the background of scrub typhus seroprevalence and the associated risk factors at community level, serosurveys during both lean and epidemic periods (phase 1 and phase 2, respectively) of AES outbreaks were conducted in this region. Methods Two community-based serosurveys were conducted during lean (April-May 2016) and epidemic AES (October-November 2016) periods. A total of 1085 and 906 individuals were enrolled during lean and epidemic AES periods, respectively, from different villages reporting recent AES cases. Scrub typhus-seronegative individuals (n=254) during the lean period were tested again during the epidemic period to estimate the incidence of scrub typhus. Results The seroprevalence of Orientia tsutsugamushi during AES epidemic period [immunoglobulin (Ig) IgG: 70.8%, IgM: 4.4%] was high as compared to that of lean AES period (IgG: 50.6%, P <0.001; IgM: 3.4%). The factors independently associated with O. tsutsugamushi positivity during lean AES period were female gender, illiteracy, not wearing footwear, not taking bath after work whereas increasing age, close contact with animals, source of drinking water and open-air defecation emerged as additional risk factors during the epidemic AES season. IgM positivity was significantly higher among febrile individuals compared to those without fever (7.7 vs. 3.5%, P=0.006). The seroincidence for O. tsutsugamushi was 19.7 per cent, and the subclinical infection rate was 54 per cent. Interpretation & conclusions The community-based surveys identified endemicity of O. tsutsugamushi and the associated risk factors in Gorakhpur region. The findings will be helpful for planning appropriate interventional strategies to control scrub typhus.
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Affiliation(s)
- Suchit Kamble
- Division of Epidemiology & Biostatistics, ICMR-National AIDS Research Institute, Pune, Maharashtra, India
| | - Arati Mane
- Division of Microbiology, ICMR-National AIDS Research Institute, Pune, Maharashtra, India
| | - Suvarna Sane
- Division of Epidemiology & Biostatistics, ICMR-National AIDS Research Institute, Pune, Maharashtra, India
| | - Suvarna Sonavale
- Division of Epidemiology & Biostatistics, ICMR-National AIDS Research Institute, Pune, Maharashtra, India
| | - Pallavi Vidhate
- Division of Microbiology, ICMR-National AIDS Research Institute, Pune, Maharashtra, India
| | - Manish Kumar Singh
- Department of Community Medicine, BRD Medical College, Gorakhpur, Uttar Pradesh, India
| | | | - Mohan Gupte
- Indian Council of Medical Research, New Delhi, India
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Thangaraj JWV, Zaman K, Shete V, Pandey AK, Velusamy S, Deoshatwar A, Mittal M, Gupta N, Murhekar M. Effectiveness of Presumptive Treatment of Acute Febrile Illness With Doxycycline or Azithromycin in Preventing Acute Encephalitis Syndrome in Gorakhpur, India: A Cohort Study. Indian Pediatr 2020; 57:619-24. [DOI: 10.1007/s13312-020-1889-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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19
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Fox-Lewis A, Hopkins J, Sar P, Sao S, Pheaktra N, Day NPJ, Blacksell SD, Turner P. Seroprevalence of Dengue Virus and Rickettsial Infections in Cambodian Children. Am J Trop Med Hyg 2020; 100:635-638. [PMID: 30675849 PMCID: PMC6402902 DOI: 10.4269/ajtmh.18-0865] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Scrub typhus (ST, Orientia tsutsugamushi), murine typhus (MT, Rickettsia typhi), and dengue virus (DENV) are important causes of childhood morbidity in Cambodia. This prospective, cross-sectional seroprevalence study determined the proportion of Cambodian children infected by these pathogens and the ages at which initial infection is likely to occur. A total of 993 patient serum samples were tested for MT- and ST-specific IgG, and 837 samples tested for DENV-specific IgG. Overall, ST, MT, and DENV seroprevalence was high, estimated at 4.2%, 5.3%, and 50.7%, respectively. Scrub typhus and MT seropositivity peaked in children aged 8–11 and 12–15 years, respectively, suggesting initial infection occurs in these ages. Dengue virus seroprevalence steadily increased with age, indicating constant DENV exposure. The results of this study suggest that in Cambodian children presenting with undifferentiated febrile illness, dengue should be considered high in the list of differential diagnoses, and empirical anti-rickettsial antimicrobial therapy may be more indicated in 8- to 15-year-olds.
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Affiliation(s)
- Andrew Fox-Lewis
- Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Jill Hopkins
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom.,Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - Poda Sar
- Angkor Hospital for Children, Siem Reap, Cambodia.,Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - Sena Sao
- Angkor Hospital for Children, Siem Reap, Cambodia.,Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | | | - Nicholas P J Day
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Stuart D Blacksell
- Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Paul Turner
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom.,Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
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Sankar S, Saravanan N, Rajendiran P, Ramamurthy M, Sasimohan A, Vineeta V, Varghese G, Idikula M, Jesudason M, Mangalakumar R, Nair A, Babujanarthanam R, Nandagopal B, Sridharan G. Detection of scrub typhus by real-time polymerase chain reaction and immunoglobulin M ELISA among patients with acute febrile illness. J Nat Sci Biol Med 2020. [DOI: 10.4103/jnsbm.jnsbm_156_19] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
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Schmidt WP, Devamani CS, Rose W, Alexander N, Prakash JAJ. Antibody response following scrub typhus infection: clinical cohort study. Trop Med Int Health 2019; 24:1455-1464. [PMID: 31660667 DOI: 10.1111/tmi.13322] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
OBJECTIVE Scrub typhus is a common cause of fever in Asia. The antibody response to infection and its effect on subsequent infection are unclear. We studied the IgM and IgG antibody response after infection, accounting for clinical severity. METHOD We studied 197 scrub typhus patients for up to 2 years post-infection. Overall, 501 blood samples were analysed for scrub typhus antibodies using ELISA. IgM and IgG ELISA optical densities (OD) were analysed using quantile regression. OD values of 1.0 (IgM) and 1.5 (IgG) were used to define seropositivity. RESULTS IgM OD values fell rapidly from an initial peak after infection. 50% of cases were IgM seronegative after 82 days. About 2 years after fever onset, 50% of cases had fitted IgG OD values of <1.5. Patients with high initial IgG OD values (≥2.5, used as a proxy for probable previous scrub typhus infection) had a more sustained IgG response than those with a low initial IgG OD, and more often presented with complications (18/36 = 50% vs. 28/91 = 30.8%, risk ratio = 1.63, 95% CI 1.04, 2.55, P = 0.035). This association was robust to adjusting for age (risk ratio 1.50, 95% CI 0.96, 2.33, P = 0.072). CONCLUSION Cross-sectional IgG seroprevalence data substantially underestimate the proportion in a population ever infected with scrub typhus. A high initial IgG as a potential marker for previous scrub typhus infection may be associated with long-term IgG persistence and a higher risk of complicated scrub typhus.
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Affiliation(s)
- Wolf-Peter Schmidt
- Department of Emergency Medicine, Christian Medical College, Vellore, India.,Department for Disease Control, London School of Hygiene and Tropical Medicine, London, UK
| | - Carol S Devamani
- Department of Rural Unit for Health and Social Affairs, Christian Medical College, Vellore, India
| | - Winsley Rose
- Department of Pediatrics and Pediatric Infectious Diseases, Christian Medical College, Vellore, India
| | - Neal Alexander
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - John A J Prakash
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
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22
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Boyle MJ, Chan JA, Handayuni I, Reiling L, Feng G, Hilton A, Kurtovic L, Oyong D, Piera KA, Barber BE, William T, Eisen DP, Minigo G, Langer C, Drew DR, de Labastida Rivera F, Amante FH, Williams TN, Kinyanjui S, Marsh K, Doolan DL, Engwerda C, Fowkes FJI, Grigg MJ, Mueller I, McCarthy JS, Anstey NM, Beeson JG. IgM in human immunity to Plasmodium falciparum malaria. Sci Adv 2019; 5:eaax4489. [PMID: 31579826 PMCID: PMC6760923 DOI: 10.1126/sciadv.aax4489] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2019] [Accepted: 09/03/2019] [Indexed: 05/15/2023]
Abstract
Most studies on human immunity to malaria have focused on the roles of immunoglobulin G (IgG), whereas the roles of IgM remain undefined. Analyzing multiple human cohorts to assess the dynamics of malaria-specific IgM during experimentally induced and naturally acquired malaria, we identified IgM activity against blood-stage parasites. We found that merozoite-specific IgM appears rapidly in Plasmodium falciparum infection and is prominent during malaria in children and adults with lifetime exposure, together with IgG. Unexpectedly, IgM persisted for extended periods of time; we found no difference in decay of merozoite-specific IgM over time compared to that of IgG. IgM blocked merozoite invasion of red blood cells in a complement-dependent manner. IgM was also associated with significantly reduced risk of clinical malaria in a longitudinal cohort of children. These findings suggest that merozoite-specific IgM is an important functional and long-lived antibody response targeting blood-stage malaria parasites that contributes to malaria immunity.
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Affiliation(s)
- M. J. Boyle
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Corresponding author. (M.J.B.); (J.G.B.)
| | - J. A. Chan
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | - I. Handayuni
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
| | - L. Reiling
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | - G. Feng
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
| | - A. Hilton
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | - L. Kurtovic
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
- Department of Immunology and Pathology, Monash University, Melbourne, Victoria, Australia
| | - D. Oyong
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- Charles Darwin University, Darwin, Northern Territory, Australia
| | - K. A. Piera
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
| | - B. E. Barber
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia
| | - T. William
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia
- Gleneagles Hospital Kota Kinabalu Sabah, Malaysia
| | - D. P. Eisen
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - G. Minigo
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- Charles Darwin University, Darwin, Northern Territory, Australia
| | - C. Langer
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | - D. R. Drew
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
| | | | - F. H. Amante
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - T. N. Williams
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Imperial College, London, UK
| | - S. Kinyanjui
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - K. Marsh
- Kenya Medical Research Institute (KEMRI), Centre for Geographic Medicine, Coast, KEMRI-Wellcome Trust Research Programme, Kilifi, Kenya
- Nuffield Department of Medicine, University of Oxford, Oxford, UK
| | - D. L. Doolan
- Australian Institute of Tropical Health and Medicine, James Cook University, Cairns, Queensland, Australia
| | - C. Engwerda
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
| | - F. J. I. Fowkes
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
- Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Melbourne, Victoria, Australia
- Department of Epidemiology and Preventive Medicine, Department of Infectious Diseases, Monash University, Melbourne, Victoria, Australia
| | - M. J. Grigg
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- Infectious Diseases Society Sabah-Menzies School of Health Research Clinical Research Unit, Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia
| | - I. Mueller
- Walter and Eliza Hall Institute, Melbourne, Victoria, Australia
- Department of Medical Biology, University of Melbourne, Melbourne, Victoria, Australia
- Department of Parasites and Insect Vectors, Institute Pasteur, Paris, France
| | - J. S. McCarthy
- QIMR Berghofer Medical Research Institute, Brisbane, Queensland, Australia
- The University of Queensland, Brisbane, Queensland, Australia
| | - N. M. Anstey
- Global and Tropical Health Division, Menzies School of Health Research, Darwin, Northern Territory, Australia
- Charles Darwin University, Darwin, Northern Territory, Australia
| | - J. G. Beeson
- Burnet Institute for Medical Research and Public Health, Melbourne, Victoria, Australia
- Department of Medicine, University of Melbourne, Melbourne, Victoria, Australia
- Department of Microbiology and Central Clinical School, Monash University, Melbourne, Victoria, Australia
- Corresponding author. (M.J.B.); (J.G.B.)
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23
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Thangaraj JWV, Vasanthapuram R, Machado L, Arunkumar G, Sodha SV, Zaman K, Bhatnagar T, Hameed SKS, Kumar A, Abdulmajeed J, Velayudhan A, Deoshatwar A, Desai AS, Kumar KH, Gupta N, Laserson K, Murhekar M. Risk Factors for Acquiring Scrub Typhus among Children in Deoria and Gorakhpur Districts, Uttar Pradesh, India, 2017. Emerg Infect Dis 2019; 24:2364-2367. [PMID: 30457537 PMCID: PMC6256400 DOI: 10.3201/eid2412.180695] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Scrub typhus is associated with outbreaks of acute encephalitis syndrome in Uttar Pradesh, India. A case-control study indicated that children residing, playing, or visiting fields; living with firewood stored indoors; handling cattle fodder; and practicing open defecation were at increased risk for scrub typhus. Communication messages should focus on changing these behaviors.
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24
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Affiliation(s)
- Anurag Bhargava
- Department of Medicine, Yenepoya Medical College, Mangalore, Karnataka, India
- Center for Nutrition Studies, Yenepoya (Deemed to be University), Mangalore, Karnataka, India
- Department of Medicine, McGill University, Montreal, Canada
| | - Ravikar Ralph
- Department of Medicine, Christian Medical College, Vellore, Tamil Nadu, India
| | - Biswaroop Chatterjee
- Department of Microbiology, IQ City Medical College, Durgapur, West Bengal, India
| | - Emmanuel Bottieau
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
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