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Dahiya B, Mehta N, Soni A, Mehta PK. Diagnosis of extrapulmonary tuberculosis by GeneXpert MTB/RIF Ultra assay. Expert Rev Mol Diagn 2023; 23:561-582. [PMID: 37318829 DOI: 10.1080/14737159.2023.2223980] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 06/06/2023] [Indexed: 06/17/2023]
Abstract
INTRODUCTION Diagnosis of extrapulmonary tuberculosis (EPTB) is an arduous task owing to different anatomical locations, unusual clinical presentations, and sparse bacillary load in clinical specimens. Although GeneXpert® MTB/RIF is a windfall in TB diagnostics including EPTB, it yields low sensitivities but high specificities in many EPTB specimens. To further improve the sensitivity of GeneXpert®, GeneXpert® Ultra, a fully nested real-time PCR targeting IS6110, IS1081 and rpoB (Rv0664) has been endorsed by the WHO (2017), wherein melt curve analysis is utilized to detect rifampicin-resistance (RIF-R). AREA COVERED We described the assay chemistry/work design of Xpert Ultra and evaluated its performance in several EPTB types, that is, TB lymphadenitis, TB pleuritis, TB meningitis, and so on, against the microbiological reference standard or composite reference standard. Notably, Xpert Ultra exhibited better sensitivities than Xpert, but mostly at the compensation of specificity values. Moreover, Xpert Ultra exhibited low false-negative and false-positive RIF-R results, compared with Xpert. We also detailed other molecular tests, that is, Truenat MTBTM/TruPlus, commercial real-time PCR, line probe assay, and so on, for EPTB diagnosis. EXPERT OPINION A combination of clinical features, imaging, histopathological findings, and Xpert Ultra are adequate for definite EPTB diagnosis so as to initiate an early anti-tubercular therapy.
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Affiliation(s)
- Bhawna Dahiya
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
| | - Neeru Mehta
- Department of Medical Electronics, Ambedkar Delhi Skill & Entrepreneurship University, Shakarpur, New Delhi, India
| | - Aishwarya Soni
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
- Department of Biotechnology, Deenbandhu Chhotu Ram University of Science and Technology, Murthal, Sonipat, India
| | - Promod K Mehta
- Centre for Biotechnology, Maharshi Dayanand University, Rohtak, India
- Microbiology Department, Faculty of Allied Health Sciences, SGT University, Budhera, Gurgaon, India
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Nyawo GR, Naidoo CC, Wu B, Sulaiman I, Clemente JC, Li Y, Minnies S, Reeve BWP, Moodley S, Rautenbach C, Wright C, Singh S, Whitelaw A, Schubert P, Warren R, Segal L, Theron G. More than Mycobacterium tuberculosis: site-of-disease microbial communities, and their functional and clinical profiles in tuberculous lymphadenitis. Thorax 2023; 78:297-308. [PMID: 36598079 PMCID: PMC9957952 DOI: 10.1136/thorax-2022-219103] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 10/31/2022] [Indexed: 12/13/2022]
Abstract
BACKGROUND Lymphadenitis is the most common extrapulmonary tuberculosis (EPTB) manifestation. The microbiome is important to human health but uninvestigated in EPTB. We profiled the site-of-disease lymph node microbiome in tuberculosis lymphadenitis (TBL). METHODS Fine-needle aspiration biopsies were collected from 158 pretreatment presumptive TBL patients in Cape Town, South Africa. 16S Illumina MiSeq rRNA gene sequencing was done. RESULTS We analysed 89 definite TBLs (dTBLs) and 61 non-TBLs (nTBLs), which had similar α- but different β-diversities (p=0.001). Clustering identified five lymphotypes prior to TB status stratification: Mycobacterium-dominant, Prevotella-dominant and Streptococcus-dominant lymphotypes were more frequent in dTBLs whereas a Corynebacterium-dominant lymphotype and a fifth lymphotype (no dominant taxon) were more frequent in nTBLs. When restricted to dTBLs, clustering identified a Mycobacterium-dominant lymphotype with low α-diversity and non-Mycobacterium-dominated lymphotypes (termed Prevotella-Corynebacterium, Prevotella-Streptococcus). The Mycobacterium dTBL lymphotype was associated with HIV-positivity and features characteristic of severe lymphadenitis (eg, larger nodes). dTBL microbial communities were enriched with potentially proinflammatory microbial short-chain fatty acid metabolic pathways (propanoate, butanoate) vs nTBLs. 11% (7/61) of nTBLs had Mycobacterium reads BLAST-confirmed as Mycobacterium tuberculosis complex. CONCLUSIONS TBL at the site-of-disease is not microbially homogeneous. Distinct microbial community clusters exist that, in our setting, are associated with different clinical characteristics, and immunomodulatory potentials. Non-Mycobacterium-dominated dTBL lymphotypes, which contain taxa potentially targeted by TB treatment, were associated with milder, potentially earlier stage disease. These investigations lay foundations for studying the microbiome's role in lymphatic TB. The long-term clinical significance of these lymphotypes requires prospective validation.
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Affiliation(s)
- Georgina R Nyawo
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
- African Microbiome Institute, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Charissa C Naidoo
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
- African Microbiome Institute, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Benjamin Wu
- Division of Pulmonary and Critical Care Medicine, New York University Grossman School of Medicine, NYU Langone Health, New York, NY, USA
| | - Imran Sulaiman
- Division of Pulmonary and Critical Care Medicine, New York University Grossman School of Medicine, NYU Langone Health, New York, NY, USA
| | - Jose C Clemente
- Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA
| | - Yonghua Li
- Division of Pulmonary and Critical Care Medicine, New York University Grossman School of Medicine, NYU Langone Health, New York, NY, USA
| | - Stephanie Minnies
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Byron W P Reeve
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Suventha Moodley
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
- African Microbiome Institute, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Cornelia Rautenbach
- National Health Laboratory Service, Tygerberg Hospital, Cape Town, Western Cape, South Africa
- Division of Medical Microbiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Colleen Wright
- Division Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Shivani Singh
- Division of Pulmonary and Critical Care Medicine, New York University Grossman School of Medicine, NYU Langone Health, New York, NY, USA
| | - Andrew Whitelaw
- National Health Laboratory Service, Tygerberg Hospital, Cape Town, Western Cape, South Africa
- Division of Medical Microbiology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Pawel Schubert
- National Health Laboratory Service, Tygerberg Hospital, Cape Town, Western Cape, South Africa
- Division Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Robin Warren
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
| | - Leopoldo Segal
- Division of Pulmonary and Critical Care Medicine, New York University Grossman School of Medicine, NYU Langone Health, New York, NY, USA
| | - Grant Theron
- DSI-NRF Centre of Excellence for Biomedical Tuberculosis Research; South African Medical Research Council Centre for Tuberculosis Research; Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
- African Microbiome Institute, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, Western Cape, South Africa
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Wang C, Sun L, Li Q, Lu H. Xpert MTB/RIF Ultra in the auxiliary diagnosis of tuberculosis among people living with human immunodeficiency virus. Drug Discov Ther 2022; 16:305-308. [PMID: 36529510 DOI: 10.5582/ddt.2022.01082] [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: 12/23/2022]
Abstract
Clinical diagnosis of tuberculosis (TB) in people living with the human immunodeficiency virus (HIV) poses a challenge. The Xpert MTB/RIF Ultra (Ultra) has displayed greater sensitivity at diagnosing tuberculosis and rifampicin resistance compared to the Xpert MTB/RIF (Xpert). However, whether Ultra is able to facilitate an auxiliary diagnosis of TB in patients with an HIV-TB co-infection remains unclear. Accordingly, the current study evaluated the use of Ultra in patients with an HIV-TB co-infection by summarizing relevant studies. The sensitivity and specificity of Ultra and Xpert at diagnosing patients with an HIV-TB co-infection have been summarized and compared. The performance of Ultra in diagnosing extrapulmonary tuberculosis was also summarized. Although a large-cohort, multi-center study needs to be conducted to assess Ultra's ability to detect TB in AIDS patients in the future, the current evidence supports the use of Ultra for the assessment of patients with an HIV-TB co-infection.
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Affiliation(s)
- Cheng Wang
- National Clinical Research Centre for Infectious Diseases, The Third People's Hospital of Shenzhen and The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, China.,School of Public Health, Bengbu Medical College, Bengbu, Anhui, China
| | - Liqin Sun
- National Clinical Research Centre for Infectious Diseases, The Third People's Hospital of Shenzhen and The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Qian Li
- National Clinical Research Centre for Infectious Diseases, The Third People's Hospital of Shenzhen and The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, China
| | - Hongzhou Lu
- National Clinical Research Centre for Infectious Diseases, The Third People's Hospital of Shenzhen and The Second Affiliated Hospital of Southern University of Science and Technology, Shenzhen, Guangdong, China
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Hou J, Liu XJ, He Y, Zhang YA, Wang MS. Cerebrospinal fluid findings of infant tuberculous meningitis: a scoping review. Ann Med 2022; 54:2517-2521. [PMID: 36120927 PMCID: PMC9518261 DOI: 10.1080/07853890.2022.2123560] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
BACKGROUND Cerebrospinal fluid (CSF) examinations play an important role in the diagnosis of tuberculous meningitis (TBM). However, their yield in the diagnosis of infant TBM remains unclear. This scoping review aims to detail the role of CSF examination for the diagnosis of infant TBM. METHODS A comprehensive literature search of PubMed, EBSCO, Embase, Scopus, Web of Science, ClinicalTrials.gov, and Cochrane Central Register of Controlled Trials was performed to identify articles published prior to October 14th, 2021. Articles describing the results of CSF exanimations among infant TBM were eligible for inclusion. Data extracted from each study included age, sex, CSF microbiological evidence (such as AFB smear, TB PCR, and TB culture), and routine CSF examinations (such as appearance, red blood cell count, white blood cell count, protein, and glucose). RESULTS A total of 98 cases were included in the final analysis. The yield of microbiological methods was listed as follows: CSF AFB smear, 20.5% (9/44); CSF TB culture 47.5% (29/61); CSF TB PCR, 65.0% (26/40); the combination of them, 57.3% (47/82). According to Marais criteria, the positivities of CSF examinations were calculated as follows: WBC count (ref, 50-500/μL), 65.5% (55/84); lymphocyte predominance (ref, >0.5), 75.4% (49/65); total protein (ref, >100 mg/dL), 67.8% (59/87); glucose (ref, <2.2 mmol/L, or CSF/serum ratio < 0.5), 68.2% (58/85). CONCLUSIONS Our data demonstrated that routine microbiological tools for infant TBM diagnosis have a sensitivity ranging from 20.5% to 65.0%, and most CSF features are non-specific and insufficient to predict a diagnosis of infant TBM. Therefore, further effort is required to develop new tools for infant TBM diagnosis.Key messages: Routine microbiological tools (such as acid-fast bacilli smear, PCR, and culture) have an unsatisfactory sensitivity for infant TBM diagnosis, and most CSF features are non-specific and insufficient to predict a diagnosis of infant TBM. Therefore, further effort is required to develop new tools for infant TBM diagnosis.
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Affiliation(s)
- Jie Hou
- Department of Intensive Care, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China
| | - Xin-Jie Liu
- Department of Pediatrics, Qilu Hospital, Cheeloo College of Medicine, Shandong University, Jinan, China
| | - Yu He
- Department of Clinical Laboratory, First Affiliated Hospital of Guangxi Medical University, Nanning, China
| | - Yan-An Zhang
- Department of Cardiovascular Surgery, Shandong Public Health Clinical Center, Cheeloo College of Medicine, Shandong University, Jinan, China.,Shandong Key Laboratory of Infectious Respiratory Disease, Jinan, China
| | - Mao-Shui Wang
- Shandong Key Laboratory of Infectious Respiratory Disease, Jinan, China.,Department of Lab Medicine, Shandong Public Health Clinical Center, Cheeloo College of Medicine, Shandong University, Jinan, China
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Huynh J, Donovan J, Phu NH, Nghia HDT, Thuong NTT, Thwaites GE. Tuberculous meningitis: progress and remaining questions. Lancet Neurol 2022; 21:450-464. [PMID: 35429482 DOI: 10.1016/s1474-4422(21)00435-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2021] [Revised: 10/03/2021] [Accepted: 11/25/2021] [Indexed: 12/23/2022]
Abstract
Tuberculous meningitis is a devastating brain infection that is caused by Mycobacterium tuberculosis and is notoriously difficult to diagnose and treat. New technologies characterising the transcriptome, proteome, and metabolome have identified new molecules and pathways associated with tuberculous meningitis severity and poor outcomes that could offer novel diagnostic and therapeutic targets. The next-generation GeneXpert MTB/RIF Ultra assay, when used on CSF, offers diagnostic sensitivity for tuberculous meningitis of approximately 70%, although it is not widely available and a negative result cannot rule out tuberculous meningitis. Small trials indicate that clinical outcomes might be improved with increased doses of rifampicin, the addition of linezolid or fluoroquinolones to standard antituberculosis therapy, or treatment with adjunctive aspirin combined with corticosteroids. Large phase 3 clinical trials are underway worldwide to address these and other questions concerning the optimal management of tuberculous meningitis; these studies also form a platform for studying pathogenesis and identifying novel diagnostic and treatment strategies, by allowing the implementation of new genomic, transcriptomic, proteomic, and metabolomic technologies in nested substudies.
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Affiliation(s)
- Julie Huynh
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK; Oxford University Clinical Research Unit, Centre for Tropical Medicine, Ho Chi Minh City, Vietnam
| | - Joseph Donovan
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK; Oxford University Clinical Research Unit, Centre for Tropical Medicine, Ho Chi Minh City, Vietnam
| | - Nguyen Hoan Phu
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK; Vietnam National University School of Medicine, Ho Chi Minh City, Vietnam
| | - Ho Dang Trung Nghia
- Hospital for Tropical Diseases, Ho Chi Minh City, Vietnam; Pham Ngoc Thach University of Medicine, Ho Chi Minh City, Vietnam
| | - Nguyen Thuy Thuong Thuong
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK; Oxford University Clinical Research Unit, Centre for Tropical Medicine, Ho Chi Minh City, Vietnam
| | - Guy E Thwaites
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, Oxford University, Oxford, UK; Oxford University Clinical Research Unit, Centre for Tropical Medicine, Ho Chi Minh City, Vietnam.
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Saylor D. Neurologic Complications of Tuberculosis. Continuum (Minneap Minn) 2021; 27:992-1017. [PMID: 34623101 DOI: 10.1212/con.0000000000001005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
PURPOSE OF REVIEW This article describes the current epidemiology, common clinical characteristics, and up-to-date evidence-based approaches to the diagnosis and management of the most common neurologic complications of tuberculosis (TB): tuberculous meningitis, intracranial tuberculoma, and spinal TB. RECENT FINDINGS Central nervous system (CNS) TB remains common and associated with significant mortality and neurologic sequelae worldwide. Human immunodeficiency virus (HIV) co-infection is strongly associated with both the development of and mortality due to CNS TB. Strongyloides co-infection is associated with reduced CNS inflammation and improved outcomes in the setting of tuberculous meningitis. Stroke remains a common complication of tuberculous meningitis, and emerging evidence suggests aspirin may be used in this context. Although a recent nucleic acid amplification test has demonstrated suboptimal sensitivity in the diagnosis of CNS TB, emerging diagnostic techniques include cell-free DNA, peripheral blood microRNA, metagenomic next-generation sequencing, and advanced imaging techniques, but these are not yet well validated. CNS TB is associated with high mortality even with current treatment regimens, although novel, promising strategies for treatment are under investigation, including a combination of IV isoniazid and ethambutol and high-dose rifampicin. SUMMARY TB can affect the nervous system in various ways and is associated with high mortality. Diagnosis remains challenging in endemic settings, with empiric treatment often initiated without a definitive diagnosis. Furthermore, optimal treatment regimens remain uncertain because current treatment for all forms of CNS TB is extrapolated from trials of tuberculous meningitis whereas the role of steroids in people with HIV and tuberculous meningitis remains controversial.
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Hai HT, Sabiiti W, Thu DDA, Phu NH, Gillespie SH, Thwaites GE, Thuong NTT. Evaluation of the molecular bacterial load assay for detecting viable Mycobacterium tuberculosis in cerebrospinal fluid before and during tuberculous meningitis treatment. Tuberculosis (Edinb) 2021; 128:102084. [PMID: 33965677 PMCID: PMC8204225 DOI: 10.1016/j.tube.2021.102084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2021] [Revised: 04/23/2021] [Accepted: 04/26/2021] [Indexed: 12/03/2022]
Abstract
New tools to monitor treatment response and predict outcome from tuberculous meningitis (TBM) are urgently required. We retrospectively evaluated the 16S rRNA-based molecular bacterial load assay (MBLA) to quantify viable Mycobacterium tuberculosis in serial cerebrospinal fluid (CSF) from adults with TBM. 187 CSF samples were collected before and during the first two months of treatment from 99 adults TBM, comprising 56 definite, 43 probable or possible TBM, and 18 non-TBM and preserved at −80°C prior to MBLA. We compared MBLA against MGIT culture, GeneXpert MTB/RIF (Xpert) and Ziehl-Neelsen (ZN) smear. Before treatment, MBLA was positive in 34/99 (34.3%), significantly lower than MGIT 47/99 (47.5%), Xpert 51/99 (51.5%) and ZN smear 55/99 (55.5%). After one month of treatment, MBLA and MGIT were positive in 3/38 (7.9%) and 4/38 (10.5%), respectively, whereas Xpert and ZN smear remained positive in 19/38 (50.0%) and 18/38 (47.4%). In summary, MBLA was less likely to detect CSF bacteria before the start of treatment compared with MGIT culture, Xpert and ZN smear. MBLA and MGIT positivity fell during treatment because of detecting only viable bacteria, whereas Xpert and ZN smear remained positive for longer because of detecting both live and dead bacteria. Sample storage and processing may have reduced MBLA-detectable viable bacteria; and sampling earlier in treatment may yield more useful results. Prospective studies with CSF sampling after 1–2 weeks are warranted.
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Affiliation(s)
- Hoang Thanh Hai
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Wilber Sabiiti
- School of Medicine, Division of Infection and Global Health, University of St Andrews, United Kingdom
| | - Do Dang Anh Thu
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam
| | - Nguyen Hoan Phu
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Hospital for Tropical Diseases, Ho Chi Minh City, Viet Nam
| | - Stephen H Gillespie
- School of Medicine, Division of Infection and Global Health, University of St Andrews, United Kingdom
| | - Guy E Thwaites
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Nuffield Department of Medicine, University of Oxford, United Kingdom
| | - Nguyen Thuy Thuong Thuong
- Oxford University Clinical Research Unit, Ho Chi Minh City, Viet Nam; Nuffield Department of Medicine, University of Oxford, United Kingdom.
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