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Aslam S, Abbas S, Nizamuddin S, Shehbaz M, Parveen A, Sultan F, Raza A. Clinical presentation and outcome of enteric fever in adult patients with cancer: a perspective from Pakistan. Access Microbiol 2024; 6:000719.v3. [PMID: 38868370 PMCID: PMC11165633 DOI: 10.1099/acmi.0.000719.v3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Accepted: 03/19/2024] [Indexed: 06/14/2024] Open
Abstract
Introduction. Enteric fever is a significant health concern in endemic countries. While extensive research has been conducted to understand its presentation and outcomes in non-cancer patients, limited data exist on its impact on cancer patients. This descriptive study aims to investigate the clinical presentation and outcome in cancer patients. Methodology. This retrospective observational study analysed 90 adult cancer patients from a single centre in Pakistan from January 2017 to December 2022. Inclusion criteria involved documented blood culture infections with Salmonella typhi or paratyphi A, B, or C. We examined clinical presentation, laboratory parameters, antimicrobial resistance, complications, and outcomes. Additionally, we explored the effects of chemotherapy, comorbidities, type of malignancy, and patient age on complications and mortality. Results. Salmonella typhi was the most prevalent organism (72.2 %), followed by Salmonella paratyphi A (22.2 %) and B (5.5 %). Variably-resistant isolates constituted 51.5 %, multi-drug resistant (MDR) isolates accounted for 20 %, extensively drug-resistant (XDR) for 14.4 % and ESBL-producers for 15.5 %, of all enteric fever infections. Enteric fever-associated complications were observed in 21.1 % of cases. Chemotherapy in the preceding month did not affect mortality, nor did age, gender, or malignancy type. However, comorbidities were statistically significant for mortality (p-value 0.03). A total of 8.8 % of patients required ICU care, and the all-cause 30 day mortality rate was 13.3 % Conclusion. Enteric fever remains prevalent in our geographical region. Unlike non-typhoidal Salmonella (NTS), enteric fever does not behave differently in an immunocompromised population, including cancer patients.
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Affiliation(s)
- Seemal Aslam
- Fellow Infectious Diseases, Department of Internal Medicine, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Salma Abbas
- Consultant Internal Medicine & Infectious Diseases, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Summiya Nizamuddin
- Consultant Medical Microbiologist, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Muhammad Shehbaz
- Fellow Infectious Diseases, Department of Internal Medicine, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Azra Parveen
- Consultant Internal Medicine & Infectious Diseases, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Faisal Sultan
- Consultant Internal Medicine & Infectious Diseases, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
| | - Aun Raza
- Consultant Internal Medicine & Infectious Diseases, Shaukat Khanum Memorial Cancer Hospital and Research Centre, Lahore, Pakistan
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Vij S, Thakur R, Singh RP, Kumar R, Pathania P, Gupta V, Suri CR, Rishi P. Dual immunization with CdtB protein and flagellin epitope offers augmented protection against enteric fever in mice. Life Sci 2023; 334:122216. [PMID: 37918629 DOI: 10.1016/j.lfs.2023.122216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 10/17/2023] [Accepted: 10/25/2023] [Indexed: 11/04/2023]
Abstract
AIMS Present study has explored the protective response of dual immunization using two different antigenic entities (i.e. flagellin epitope and cytolethal distending toxin subunit B (CdtB) protein) against lethal challenge of typhoidal serovars in a murine model. MAIN METHODS In-vitro immunogenicity of flagellin epitope-BSA conjugate and CdtB protein was confirmed using Indirect ELISA of typhoid positive patients' sera. Further, both entities were administered intraperitoneally in mice individually or in combination, followed by lethal challenge of typhoidal Salmonellae. Various parameters were analysed such as bacterial burden, mice survival, histopathological analysis, cytokine analysis and immunophenotyping. Serum samples obtained from the immunized mice were used for passive immunization studies, wherein mice survival and mechanism of action of the generated antibodies was studied. KEY FINDINGS Active immunization studies using the combination of both entities demonstrated improved mice survival after lethal challenge with typhoidal Salmonellae, reduced bacterial burden in organs, expression of immunophenotypic markers in splenocytes and restored tissue histoarchitecture. When used in combination, the effective doses of both the candidates reduced which may be attributed to multiprong approach used by the immune system to recognize Salmonella. Passive immunization studies further determined the protective efficacy of generated antibodies by different mechanisms such as complement mediated bactericidal action, swarming inhibition and increased phagocytic uptake. SIGNIFICANCE Present study is the first phase of the proof-of-concept which may prove to be beneficial in developing an effective bi-functional vaccine candidate to render protection against both Vi-positive as well as Vi-negative Salmonella strains.
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Affiliation(s)
- Shania Vij
- Department of Microbiology, Panjab University, Chandigarh 160014, India.
| | - Reena Thakur
- Department of Microbiology, Panjab University, Chandigarh 160014, India
| | | | - Rashmi Kumar
- CSIR-Institute of Microbial Technology (IMTech), Chandigarh 160036, India
| | - Preeti Pathania
- CSIR-Institute of Microbial Technology (IMTech), Chandigarh 160036, India
| | - Varsha Gupta
- Department of Microbiology, Government Medical College and Hospital (GMCH), Sector 32, Chandigarh 160030, India
| | - Chander Raman Suri
- CSIR-Institute of Microbial Technology (IMTech), Chandigarh 160036, India
| | - Praveen Rishi
- Department of Microbiology, Panjab University, Chandigarh 160014, India.
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3
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Martin LB, Khanam F, Qadri F, Khalil I, Sikorski MJ, Baker S. Vaccine value profile for Salmonella enterica serovar Paratyphi A. Vaccine 2023; 41 Suppl 2:S114-S133. [PMID: 37951691 DOI: 10.1016/j.vaccine.2023.01.054] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2022] [Revised: 12/27/2022] [Accepted: 01/23/2023] [Indexed: 11/14/2023]
Abstract
In Asia, there are an estimated 12 million annual cases of enteric fever, a potentially fatal systemic bacterial infection caused by Salmonella enterica serovars Typhi (STy) and Paratyphi A (SPA). The recent availability of typhoid conjugate vaccines (TCV), an increasing incidence of disease caused by SPA and growing antimicrobial resistance (AMR) across the genus Salmonella makes a bivalent STy/SPA vaccine a useful public health proposition. The uptake of a stand-alone paratyphoid vaccine is likely low thus, there is a pipeline of bivalent STy/SPA candidate vaccines. Several candidates are close to entering clinical trials, which if successful should facilitate a more comprehensive approach for enteric fever control. Additionally, the World Health Organization (WHO) has made advancing the development of vaccines that protect young children and working aged adults against both agents of enteric fever a priority objective. This "Vaccine Value Profile" (VVP) addresses information related predominantly to invasive disease caused by SPA prevalent in Asia. Information is included on stand-alone SPA candidate vaccines and candidate vaccines targeting SPA combined with STy. Out of scope for the first version of this VVP is a wider discussion on the development of a universal Salmonella combination candidate vaccine, addressing both enteric fever and invasive non-typhoidal Salmonella disease, for use globally. This VVP is a detailed, high-level assessment of existing, publicly available information to inform and contextualize the public health, economic, and societal potential of pipeline vaccines and vaccine-like products for SPA. Future versions of this VVP will be updated to reflect ongoing activities such as vaccine development strategies and "Full Vaccine Value Assessment" that will inform the value proposition of an SPA vaccine. This VVP was developed by an expert working group from academia, non-profit organizations, public-private partnerships, and multi-lateral organizations as well as in collaboration with stakeholders from the WHO South-East Asian Region. All contributors have extensive expertise on various elements of the VVP for SPA and collectively aimed to identify current research and knowledge gaps.
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Affiliation(s)
- Laura B Martin
- Independent Consultant (current affiliation US Pharmacopeia Convention), USA.
| | - Farhana Khanam
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Bangladesh.
| | - Firdausi Qadri
- International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Bangladesh.
| | | | | | - Stephen Baker
- University of Cambridge School of Clinical Medicine, UK.
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4
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Carey ME, Dyson ZA, Ingle DJ, Amir A, Aworh MK, Chattaway MA, Chew KL, Crump JA, Feasey NA, Howden BP, Keddy KH, Maes M, Parry CM, Van Puyvelde S, Webb HE, Afolayan AO, Alexander AP, Anandan S, Andrews JR, Ashton PM, Basnyat B, Bavdekar A, Bogoch II, Clemens JD, da Silva KE, De A, de Ligt J, Diaz Guevara PL, Dolecek C, Dutta S, Ehlers MM, Francois Watkins L, Garrett DO, Godbole G, Gordon MA, Greenhill AR, Griffin C, Gupta M, Hendriksen RS, Heyderman RS, Hooda Y, Hormazabal JC, Ikhimiukor OO, Iqbal J, Jacob JJ, Jenkins C, Jinka DR, John J, Kang G, Kanteh A, Kapil A, Karkey A, Kariuki S, Kingsley RA, Koshy RM, Lauer AC, Levine MM, Lingegowda RK, Luby SP, Mackenzie GA, Mashe T, Msefula C, Mutreja A, Nagaraj G, Nagaraj S, Nair S, Naseri TK, Nimarota-Brown S, Njamkepo E, Okeke IN, Perumal SPB, Pollard AJ, Pragasam AK, Qadri F, Qamar FN, Rahman SIA, Rambocus SD, Rasko DA, Ray P, Robins-Browne R, Rongsen-Chandola T, Rutanga JP, Saha SK, Saha S, Saigal K, Sajib MSI, Seidman JC, Shakya J, Shamanna V, Shastri J, Shrestha R, Sia S, Sikorski MJ, Singh A, Smith AM, Tagg KA, Tamrakar D, Tanmoy AM, Thomas M, Thomas MS, Thomsen R, Thomson NR, Tupua S, Vaidya K, Valcanis M, Veeraraghavan B, Weill FX, Wright J, Dougan G, Argimón S, Keane JA, Aanensen DM, Baker S, Holt KE. Global diversity and antimicrobial resistance of typhoid fever pathogens: Insights from a meta-analysis of 13,000 Salmonella Typhi genomes. eLife 2023; 12:e85867. [PMID: 37697804 PMCID: PMC10506625 DOI: 10.7554/elife.85867] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2022] [Accepted: 08/02/2023] [Indexed: 09/13/2023] Open
Abstract
Background The Global Typhoid Genomics Consortium was established to bring together the typhoid research community to aggregate and analyse Salmonella enterica serovar Typhi (Typhi) genomic data to inform public health action. This analysis, which marks 22 years since the publication of the first Typhi genome, represents the largest Typhi genome sequence collection to date (n=13,000). Methods This is a meta-analysis of global genotype and antimicrobial resistance (AMR) determinants extracted from previously sequenced genome data and analysed using consistent methods implemented in open analysis platforms GenoTyphi and Pathogenwatch. Results Compared with previous global snapshots, the data highlight that genotype 4.3.1 (H58) has not spread beyond Asia and Eastern/Southern Africa; in other regions, distinct genotypes dominate and have independently evolved AMR. Data gaps remain in many parts of the world, and we show the potential of travel-associated sequences to provide informal 'sentinel' surveillance for such locations. The data indicate that ciprofloxacin non-susceptibility (>1 resistance determinant) is widespread across geographies and genotypes, with high-level ciprofloxacin resistance (≥3 determinants) reaching 20% prevalence in South Asia. Extensively drug-resistant (XDR) typhoid has become dominant in Pakistan (70% in 2020) but has not yet become established elsewhere. Ceftriaxone resistance has emerged in eight non-XDR genotypes, including a ciprofloxacin-resistant lineage (4.3.1.2.1) in India. Azithromycin resistance mutations were detected at low prevalence in South Asia, including in two common ciprofloxacin-resistant genotypes. Conclusions The consortium's aim is to encourage continued data sharing and collaboration to monitor the emergence and global spread of AMR Typhi, and to inform decision-making around the introduction of typhoid conjugate vaccines (TCVs) and other prevention and control strategies. Funding No specific funding was awarded for this meta-analysis. Coordinators were supported by fellowships from the European Union (ZAD received funding from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No 845681), the Wellcome Trust (SB, Wellcome Trust Senior Fellowship), and the National Health and Medical Research Council (DJI is supported by an NHMRC Investigator Grant [GNT1195210]).
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Affiliation(s)
- Megan E Carey
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical MedicineLondonUnited Kingdom
- IAVI, Chelsea & Westminster HospitalLondonUnited Kingdom
| | - Zoe A Dyson
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical MedicineLondonUnited Kingdom
- Department of Infectious Diseases, Central Clinical School, Monash UniversityMelbourneAustralia
- Wellcome Sanger Institute, Wellcome Genome CampusHinxtonUnited Kingdom
| | - Danielle J Ingle
- Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of MelbourneMelbourneAustralia
| | | | - Mabel K Aworh
- Nigeria Field Epidemiology and Laboratory Training ProgrammeAbujaNigeria
- College of Veterinary Medicine, North Carolina State UniversityRaleighUnited States
| | | | - Ka Lip Chew
- National University HospitalSingaporeSingapore
| | - John A Crump
- Centre for International Health, University of OtagoDunedinNew Zealand
| | - Nicholas A Feasey
- Department of Clinical Sciences, Liverpool School of Tropical MedicineLiverpoolUnited Kingdom
- Malawi-Liverpool Wellcome Programme, Kamuzu University of Health SciencesBlantyreMalawi
| | - Benjamin P Howden
- Centre for Pathogen Genomics, Department of Microbiology and Immunology, University of Melbourne at Doherty Institute for Infection and ImmunityMelbourneAustralia
- Microbiological Diagnostic Unit Public Health Laboratory, The University of Melbourne at the Peter Doherty Institute for Infection and ImmunityMelbourneAustralia
| | | | - Mailis Maes
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Christopher M Parry
- Department of Clinical Sciences, Liverpool School of Tropical MedicineLiverpoolUnited Kingdom
| | - Sandra Van Puyvelde
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
- University of AntwerpAntwerpBelgium
| | - Hattie E Webb
- Centers for Disease Control and PreventionAtlantaUnited States
| | - Ayorinde Oluwatobiloba Afolayan
- Global Health Research Unit (GHRU) for the Genomic Surveillance of Antimicrobial Resistance, Faculty of Pharmacy, University of IbadanIbadanNigeria
| | | | - Shalini Anandan
- Department of Clinical Microbiology, Christian Medical CollegeVelloreIndia
| | - Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford UniversityStanfordUnited States
| | - Philip M Ashton
- Malawi-Liverpool Wellcome ProgrammeBlantyreMalawi
- Institute of Infection, Veterinary and Ecological Sciences, University of LiverpoolLiverpoolUnited Kingdom
| | - Buddha Basnyat
- Oxford University Clinical Research Unit NepalKathmanduNepal
| | | | - Isaac I Bogoch
- Department of Medicine, Division of Infectious Diseases, University of TorontoTorontoCanada
| | - John D Clemens
- International Vaccine InstituteSeoulRepublic of Korea
- International Centre for Diarrhoeal Disease ResearchDhakaBangladesh
- UCLA Fielding School of Public HealthLos AngelesUnited States
- Korea UniversitySeoulRepublic of Korea
| | - Kesia Esther da Silva
- Division of Infectious Diseases and Geographic Medicine, Stanford UniversityStanfordUnited States
| | - Anuradha De
- Topiwala National Medical CollegeMumbaiIndia
| | - Joep de Ligt
- ESR, Institute of Environmental Science and Research Ltd., PoriruaWellingtonNew Zealand
| | | | - Christiane Dolecek
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of OxfordOxfordUnited Kingdom
- Mahidol Oxford Tropical Medicine Research Unit, Mahidol UniversityBangkokThailand
| | - Shanta Dutta
- ICMR - National Institute of Cholera & Enteric DiseasesKolkataIndia
| | - Marthie M Ehlers
- Department of Medical Microbiology, Faculty of Health Sciences, University of PretoriaPretoriaSouth Africa
- Department of Medical Microbiology, Tshwane Academic Division, National Health Laboratory ServicePretoriaSouth Africa
| | | | | | - Gauri Godbole
- United Kingdom Health Security AgencyLondonUnited Kingdom
| | - Melita A Gordon
- Institute of Infection, Veterinary and Ecological Sciences, University of LiverpoolLiverpoolUnited Kingdom
| | - Andrew R Greenhill
- Federation University AustraliaChurchillAustralia
- Papua New Guinea Institute of Medical ResearchGorokaPapua New Guinea
| | - Chelsey Griffin
- Centers for Disease Control and PreventionAtlantaUnited States
| | - Madhu Gupta
- Post Graduate Institute of Medical Education and ResearchChandigarhIndia
| | | | - Robert S Heyderman
- Research Department of Infection, Division of Infection and Immunity, University College LondonLondonUnited Kingdom
| | | | - Juan Carlos Hormazabal
- Bacteriologia, Subdepartamento de Enfermedades Infecciosas, Departamento de Laboratorio Biomedico, Instituto de Salud Publica de Chile (ISP)SantiagoChile
| | - Odion O Ikhimiukor
- Global Health Research Unit (GHRU) for the Genomic Surveillance of Antimicrobial Resistance, Faculty of Pharmacy, University of IbadanIbadanNigeria
| | - Junaid Iqbal
- Department of Pediatrics and Child Health, Aga Khan UniversityKarachiPakistan
| | - Jobin John Jacob
- Department of Clinical Microbiology, Christian Medical CollegeVelloreIndia
| | - Claire Jenkins
- United Kingdom Health Security AgencyLondonUnited Kingdom
| | | | - Jacob John
- Department of Community Health, Christian Medical CollegeVelloreIndia
| | - Gagandeep Kang
- Department of Community Health, Christian Medical CollegeVelloreIndia
| | - Abdoulie Kanteh
- Medical Research Council Unit The Gambia at London School Hygiene & Tropical MedicineFajaraGambia
| | - Arti Kapil
- All India Institute of Medical SciencesDelhiIndia
| | | | - Samuel Kariuki
- Centre for Microbiology Research, Kenya Medical Research InstituteNairobiKenya
| | | | | | - AC Lauer
- Centers for Disease Control and PreventionAtlantaUnited States
| | - Myron M Levine
- Center for Vaccine Development and Global Health (CVD), University of Maryland School of Medicine, Baltimore, Maryland, USABaltimoreUnited States
| | | | - Stephen P Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford UniversityStanfordUnited States
| | - Grant Austin Mackenzie
- Medical Research Council Unit The Gambia at London School Hygiene & Tropical MedicineFajaraGambia
| | - Tapfumanei Mashe
- National Microbiology Reference LaboratoryHarareZimbabwe
- World Health OrganizationHarareZimbabwe
| | | | - Ankur Mutreja
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Geetha Nagaraj
- Central Research Laboratory, Kempegowda Institute of Medical SciencesBengaluruIndia
| | | | - Satheesh Nair
- United Kingdom Health Security AgencyLondonUnited Kingdom
| | | | | | | | - Iruka N Okeke
- Global Health Research Unit (GHRU) for the Genomic Surveillance of Antimicrobial Resistance, Faculty of Pharmacy, University of IbadanIbadanNigeria
| | | | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of OxfordOxfordUnited Kingdom
- The NIHR Oxford Biomedical Research CentreOxfordUnited Kingdom
| | | | - Firdausi Qadri
- International Centre for Diarrhoeal Disease ResearchDhakaBangladesh
| | - Farah N Qamar
- Department of Pediatrics and Child Health, Aga Khan UniversityKarachiPakistan
| | | | - Savitra Devi Rambocus
- Microbiological Diagnostic Unit Public Health Laboratory, The University of Melbourne at the Peter Doherty Institute for Infection and ImmunityMelbourneAustralia
| | - David A Rasko
- Department of Microbiology and Immunology, University of Maryland School of MedicineBaltimoreUnited States
- Institute for Genome Sciences, University of Maryland School of MedicineBaltimoreUnited States
| | - Pallab Ray
- Post Graduate Institute of Medical Education and ResearchChandigarhIndia
| | - Roy Robins-Browne
- Department of Microbiology and Immunology at the Peter Doherty Institute for Infection and Immunity, The University of MelbourneMelbourneAustralia
- Murdoch Children’s Research Institute, Royal Children’s HospitalParkvilleAustralia
| | | | | | | | | | | | - Mohammad Saiful Islam Sajib
- Child Health Research FoundationDhakaBangladesh
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of GlasgowGlasgowUnited Kingdom
| | | | - Jivan Shakya
- Dhulikhel HospitalDhulikhelNepal
- Institute for Research in Science and TechnologyKathmanduNepal
| | - Varun Shamanna
- Central Research Laboratory, Kempegowda Institute of Medical SciencesBengaluruIndia
| | - Jayanthi Shastri
- Topiwala National Medical CollegeMumbaiIndia
- Kasturba Hospital for Infectious DiseasesMumbaiIndia
| | - Rajeev Shrestha
- Center for Infectious Disease Research & Surveillance, Dhulikhel Hospital, Kathmandu University HospitalDhulikhelNepal
| | - Sonia Sia
- Research Institute for Tropical Medicine, Department of HealthMuntinlupa CityPhilippines
| | - Michael J Sikorski
- Center for Vaccine Development and Global Health (CVD), University of Maryland School of Medicine, Baltimore, Maryland, USABaltimoreUnited States
- Department of Microbiology and Immunology, University of Maryland School of MedicineBaltimoreUnited States
- Institute for Genome Sciences, University of Maryland School of MedicineBaltimoreUnited States
| | | | - Anthony M Smith
- Centre for Enteric Diseases, National Institute for Communicable DiseasesJohannesburgSouth Africa
| | - Kaitlin A Tagg
- Centers for Disease Control and PreventionAtlantaUnited States
| | - Dipesh Tamrakar
- Center for Infectious Disease Research & Surveillance, Dhulikhel Hospital, Kathmandu University HospitalDhulikhelNepal
| | | | - Maria Thomas
- Christian Medical College, LudhianaLudhianaIndia
| | | | | | | | - Siaosi Tupua
- Ministry of Health, Government of SamoaApiaSamoa
| | | | - Mary Valcanis
- Microbiological Diagnostic Unit Public Health Laboratory, The University of Melbourne at the Peter Doherty Institute for Infection and ImmunityMelbourneAustralia
| | | | | | - Jackie Wright
- ESR, Institute of Environmental Science and Research Ltd., PoriruaWellingtonNew Zealand
| | - Gordon Dougan
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - Silvia Argimón
- Centre for Genomic Pathogen Surveillance, Big Data Institute, University of OxfordOxfordUnited Kingdom
| | - Jacqueline A Keane
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
| | - David M Aanensen
- Centre for Genomic Pathogen Surveillance, Big Data Institute, University of OxfordOxfordUnited Kingdom
| | - Stephen Baker
- Cambridge Institute of Therapeutic Immunology and Infectious Disease (CITIID), University of Cambridge School of Clinical Medicine, Cambridge Biomedical CampusCambridgeUnited Kingdom
- IAVI, Chelsea & Westminster HospitalLondonUnited Kingdom
| | - Kathryn E Holt
- Department of Infection Biology, Faculty of Infectious and Tropical Diseases, London School of Hygiene & Tropical MedicineLondonUnited Kingdom
- Department of Infectious Diseases, Central Clinical School, Monash UniversityMelbourneAustralia
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Chatterjee R, Chowdhury AR, Mukherjee D, Chakravortty D. From Eberthella typhi to Salmonella Typhi: The Fascinating Journey of the Virulence and Pathogenicity of Salmonella Typhi. ACS OMEGA 2023; 8:25674-25697. [PMID: 37521659 PMCID: PMC10373206 DOI: 10.1021/acsomega.3c02386] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/09/2023] [Accepted: 06/30/2023] [Indexed: 08/01/2023]
Abstract
Salmonella Typhi (S. Typhi), the invasive typhoidal serovar of Salmonella enterica that causes typhoid fever in humans, is a severe threat to global health. It is one of the major causes of high morbidity and mortality in developing countries. According to recent WHO estimates, approximately 11-21 million typhoid fever illnesses occur annually worldwide, accounting for 0.12-0.16 million deaths. Salmonella infection can spread to healthy individuals by the consumption of contaminated food and water. Typhoid fever in humans sometimes is accompanied by several other critical extraintestinal complications related to the central nervous system, cardiovascular system, pulmonary system, and hepatobiliary system. Salmonella Pathogenicity Island-1 and Salmonella Pathogenicity Island-2 are the two genomic segments containing genes encoding virulent factors that regulate its invasion and systemic pathogenesis. This Review aims to shed light on a comparative analysis of the virulence and pathogenesis of the typhoidal and nontyphoidal serovars of S. enterica.
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Affiliation(s)
- Ritika Chatterjee
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Atish Roy Chowdhury
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Debapriya Mukherjee
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
| | - Dipshikha Chakravortty
- Department
of Microbiology and Cell Biology, Division of Biological Sciences, Indian Institute of Science, Bangalore, Karnataka 560012, India
- Centre
for Biosystems Science and Engineering, Indian Institute of Science, Bangalore, Karnataka 560012, India
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Abstract
Several tropical or geographically confined infectious diseases may lead to organ failure requiring management in an intensive care unit (ICU), both in endemic low- and middle-income countries where ICU facilities are increasingly being developed and in (nonendemic) high-income countries through an increase in international travel and migration. The ICU physician must know which of these diseases may be encountered and how to recognize, differentiate, and treat them. The four historically most prevalent "tropical" diseases (malaria, enteric fever, dengue, and rickettsiosis) can present with single or multiple organ failure in a very similar manner, which makes differentiation based solely on clinical signs very difficult. Specific but frequently subtle symptoms should be considered and related to the travel history of the patient, the geographic distribution of these diseases, and the incubation period. In the future, ICU physicians may also be more frequently confronted with rare but frequently lethal diseases, such as Ebola and other viral hemorrhagic fevers, leptospirosis, and yellow fever. No one could have foreseen the worldwide 2019-up to now coronavirus disease 2019 (COVID-19) crisis caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which was initially spread by travel too. In addition, the actual pandemic due to SARS-CoV-2 reminds us of the actual and potential threat of (re)-emerging pathogens. If left untreated or when treated with a delay, many travel-related diseases remain an important cause of morbidity and even mortality, even when high-quality critical care is provided. Awareness and a high index of suspicion of these diseases is a key skill for the ICU physicians of today and tomorrow to develop.
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Muacevic A, Adler JR. Clinical and Laboratory Features of Enteric Fever in Children and Antibiotic Sensitivity Pattern in a Tertiary Care Hospital of a Low- and Middle-Income Country. Cureus 2022; 14:e30784. [PMID: 36320797 PMCID: PMC9614183 DOI: 10.7759/cureus.30784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/27/2022] [Indexed: 11/15/2022] Open
Abstract
BACKGROUND Globally, enteric fever (EF) significantly gives rise to an appalling death toll. It is an endemic illness in Bangladesh and South Asia. The condition manifests in a wide range of clinical features in children. Nowadays, antibiotic resistance is an international stumbling block that hampers the appropriate treatment and outcome of EF. OBJECTIVE The study evaluated the clinical and laboratory characteristics and antibiotic sensitivity pattern of Salmonella enterica in children. METHODS This prospective research was conducted at Delta Medical College and Hospital, Dhaka, Bangladesh, from January 2017 to December 2019. A total of 200 pediatric cases of EF were included in this study who were either culture positive or had significantly raised Widal test titer for Salmonella with suggestive clinical features. RESULTS All the patients had a fever, and most had coated tongue, vomiting, abdominal pain, organomegaly, and diarrhea. Among the selected 200 cases of EF, 43.5% were Salmonella typhi culture-positive. A high erythrocyte sedimentation rate (ESR) was observed in a substantial number (53%) of patients. Ceftriaxone was the most sensitive (100%) antibiotic through laboratory analysis, followed by cefotaxime (95.1%). Among the oral antibiotics used, cefixime (92.8%) was the most sensitive. CONCLUSION EF in children can present with varied clinical manifestations. Selective antibiotic treatment according to sensitivity patterns is crucial for effective illness management and will reduce morbidity and mortality in the pediatric population.
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Chen CH, Hsu YJ, Chen YC, Cheng SS, Kuo KC, Chiu CH. Clinical manifestations and microbiological features between indigenous and imported enteric fever in Taiwan, 2010-2020. J Formos Med Assoc 2022; 121:2644-2648. [PMID: 35871037 DOI: 10.1016/j.jfma.2022.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 06/17/2022] [Accepted: 06/19/2022] [Indexed: 11/20/2022] Open
Abstract
Previous studies had showed that indigenous clones of Salmonella Typhi and S. Paratyphi were originally imported from other countries in Taiwan. We presented the clinical manifestations and laboratory findings of indigenous and imported enteric fever cases in Taiwan in the current decade. We retrospectively reviewed typhoid and paratyphoid fever cases in two medical centers of Chang Gung Memorial Hospitals in 2010-2020. A total of 37 enteric fever cases including 24 typhoid fever and 13 paratyphoid fever were recorded. There were 20 indigenous cases, 16 imported cases, and one indetermined case. Splenomegaly and hepatitis were more frequent in typhoid fever than in paratyphoid fever (P < 0.05). Imported cases had more ciprofloxacin non-susceptibility rate (8/16, 50.0%) than indigenous cases (2/20, 10%). Indigenous ciprofloxacin non-susceptible S. Typhi isolates were found in 2018. One indigenous S. Paratyphi B isolate was multi-drug resistant (MDR) to chloramphenicol, ampicillin, and trimethoprim/sulfamethoxazole.
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Affiliation(s)
- Chih-Ho Chen
- Division of Pediatric Infectious Diseases, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan; Graduate Institute of Clinical Medical Sciences, Chang Gung University College of Medicine, Taoyuan, Taiwan; Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, TaCyuan, Taiwan
| | - Ying-Jie Hsu
- Department of Pediatrics, Chang Gung Memorial Hospital, Taipei, Taiwan; Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, TaCyuan, Taiwan
| | - Yi-Ching Chen
- Department of Pediatrics, Chang Gung Memorial Hospital, Taipei, Taiwan; Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, TaCyuan, Taiwan
| | - Shu-Shen Cheng
- Department of Laboratory Medicine, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Kuang-Che Kuo
- Division of Pediatric Infectious Diseases, Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan
| | - Cheng-Hsun Chiu
- Molecular Infectious Disease Research Center, Chang Gung Memorial Hospital, TaCyuan, Taiwan; Division of Pediatric Infectious Diseases, Chang Gung Children's Hospital, Chang Gung Memorial Hospital, Linkou, Taiwan.
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9
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Xie L, Ming L, Ding M, Deng L, Liu M, Cong Y. Paratyphoid Fever A: Infection and Prevention. Front Microbiol 2022; 13:945235. [PMID: 35875577 PMCID: PMC9304857 DOI: 10.3389/fmicb.2022.945235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 06/15/2022] [Indexed: 11/17/2022] Open
Abstract
Enteric fever is caused by Salmonella enterica serovar Typhi, Salmonella enterica serovar Paratyphi A, B, and C. While S. Typhi remains the primary causative agent of enteric fever, S. Paratyphi A is responsible for an increasing portion of enteric fever incidence. However, the current available vaccines for enteric fever are all developed from S. Typhi, and lack adequate cross immune protection against paratyphoid fever A. Therefore, paratyphoid A vaccines are urgently needed. The present paper reviews the latest progresses in pathogenesis, global burden, infection features of paratyphoid fever A, as well as the status of vaccine development, highlighting the necessity for the development of vaccines against paratyphoid fever A.
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Affiliation(s)
- Lei Xie
- Precision Medicine Center, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
| | - Lan Ming
- Department of Clinical Laboratory, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
| | - Manlin Ding
- Precision Medicine Center, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
- Department of Clinical Laboratory, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
| | - Luxin Deng
- Department of Clinical Laboratory, The Affiliated Hospital of Southwest Medical University, Luzhou, China
| | - Miao Liu
- Precision Medicine Center, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
| | - Yanguang Cong
- Precision Medicine Center, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
- Department of Clinical Laboratory, The Affiliated Traditional Chinese Medicine Hospital of Southwest Medical University, Luzhou, China
- *Correspondence: Yanguang Cong,
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10
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McCann N, Nabarro L, Morris-Jones S, Patel T, Godbole G, Heyderman R, Brown M. Outpatient management of uncomplicated enteric fever: A case series of 93 patients from the Hospital of Tropical Diseases, London. J Infect 2022; 85:397-404. [PMID: 35781016 DOI: 10.1016/j.jinf.2022.06.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Revised: 05/04/2022] [Accepted: 06/24/2022] [Indexed: 11/29/2022]
Abstract
OBJECTIVES Enteric fever is predominantly managed as an outpatient condition in endemic settings but there is little evidence to support this approach in non-endemic settings. This study aims to review the outcomes of outpatients treated for enteric fever at the Hospital of Tropical Diseases in London, UK. METHODS We conducted a retrospective analysis of all patients with confirmed enteric fever between August 2009 and September 2020. Demographic, clinical, laboratory and microbiological data were collected and compared between the inpatient and outpatient populations. Outcomes investigated were complicated enteric fever, treatment failure and relapse. RESULTS Overall, 93 patients (59% male, median age 31) were identified with blood and/or stool culture confirmed enteric fever and 49 (53%) of these were managed as outpatients. The commonest empirical treatment for outpatients was azithromycin (70%) and for inpatients was ceftriaxone (84%). Outpatients were more likely than inpatients to receive only one antibiotic (57% vs 19%, p < 0.01) and receive a shorter duration of antibiotics (median 7 vs 11 days, p <0.01). There were no cases of complicated disease or relapse in either the inpatient or outpatient groups. There was one treatment failure in the outpatient group. Azithromycin was well-tolerated with no reported side effects. CONCLUSIONS Our findings suggest that outpatient management of uncomplicated imported enteric fever is safe and effective with the use of oral azithromycin. Careful monitoring of patients is recommended as treatment failure can occur.
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Affiliation(s)
- N McCann
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK.
| | - L Nabarro
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; St George's University Hospitals NHS Foundation Trust, London, UK
| | - S Morris-Jones
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Research Department of Infection, Division of Infection and Immunity, University College London, London, UK
| | - T Patel
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK
| | - G Godbole
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Gastrointestinal Pathogens and Food Safety (One Health), United Kingdom Health Security Agency, UK
| | - R Heyderman
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Research Department of Infection, Division of Infection and Immunity, University College London, London, UK
| | - M Brown
- Hospital for Tropical Diseases, University College London Hospitals NHS Foundation Trust, London, UK; Clinical Research Department, London School of Hygiene and Tropical Medicine, London, UK
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11
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Roberts T, Luangasanatip N, Ling CL, Hopkins J, Jaksuwan R, Lubell Y, Vongsouvath M, van Doorn HR, Ashley EA, Turner P. Antimicrobial resistance detection in Southeast Asian hospitals is critically important from both patient and societal perspectives, but what is its cost? PLOS GLOBAL PUBLIC HEALTH 2021; 1:e0000018. [PMID: 34746931 PMCID: PMC7611947 DOI: 10.1371/journal.pgph.0000018] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 09/13/2021] [Indexed: 11/19/2022]
Abstract
Antimicrobial resistance (AMR) is a major threat to global health. Improving laboratory capacity for AMR detection is critically important for patient health outcomes and population level surveillance. We aimed to estimate the financial cost of setting up and running a microbiology laboratory for organism identification and antimicrobial susceptibility testing as part of an AMR surveillance programme. Financial costs for setting up and running a microbiology laboratory were estimated using a top-down approach based on resource and cost data obtained from three clinical laboratories in the Mahidol Oxford Tropical Medicine Research Unit network. Costs were calculated for twelve scenarios, considering three levels of automation, with equipment sourced from either of the two leading manufacturers, and at low and high specimen throughput. To inform the costs of detection of AMR in existing labs, the unit cost per specimen and per isolate were also calculated using a micro-costing approach. Establishing a laboratory with the capacity to process 10,000 specimens per year ranged from $254,000 to $660,000 while the cost for a laboratory processing 100,000 specimens ranged from $394,000 to $887,000. Excluding capital costs to set up the laboratory, the cost per specimen ranged from $22-31 (10,000 specimens) and $11-12 (100,000 specimens). The cost per isolate ranged from $215-304 (10,000 specimens) and $105-122 (100,000 specimens). This study provides a conservative estimate of the costs for setting up and running a microbiology laboratory for AMR surveillance from a healthcare provider perspective. In the absence of donor support, these costs may be prohibitive in many low- and middle- income country (LMIC) settings. With the increased focus on AMR detection and surveillance, the high laboratory costs highlight the need for more focus on developing cheaper and cost-effective equipment and reagents so that laboratories in LMICs have the potential to improve laboratory capacity and participate in AMR surveillance.
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Affiliation(s)
- Tamalee Roberts
- Lao- Oxford-Mahosot Hospital- Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
| | - Nantasit Luangasanatip
- Faculty of Tropical Medicine, Mahidol- Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Clare L. Ling
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Shoklo Malaria Research Unit, Mahidol- Oxford Tropical Medicine Research Unit, Mae Sot, Thailand
| | - 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
| | - Risara Jaksuwan
- Lao- Oxford-Mahosot Hospital- Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
| | - Yoel Lubell
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Faculty of Tropical Medicine, Mahidol- Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand
| | - Manivanh Vongsouvath
- Lao- Oxford-Mahosot Hospital- Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
| | - H. Rogier van Doorn
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom
- Oxford University Clinical Research Unit, National Hospital for Tropical Diseases, Hanoi, Vietnam
| | - Elizabeth A. Ashley
- Lao- Oxford-Mahosot Hospital- Wellcome Trust Research Unit, Mahosot Hospital, Vientiane, Lao People’s Democratic Republic
- 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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12
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Pragasam AK, Pickard D, Wong V, Dougan G, Kang G, Thompson A, John J, Balaji V, Mutreja A. Phylogenetic Analysis Indicates a Longer Term Presence of the Globally Distributed H58 Haplotype of Salmonella Typhi in Southern India. Clin Infect Dis 2021; 71:1856-1863. [PMID: 32003431 PMCID: PMC7643746 DOI: 10.1093/cid/ciz1112] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 01/29/2019] [Indexed: 12/28/2022] Open
Abstract
Background Typhoid fever caused by Salmonella Typhi is a major public health concern in low-/middle-income countries. A recent study of 1900 global S. Typhi indicated that South Asia might be the site of the original emergence of the most successful and hypervirulent clone belonging to the 4.3.1 genotype. However, this study had limited samples from India. Methods We analyzed 194 clinical S. Typhi, temporal representatives from those isolated from blood and bone marrow cultures in southern India, over 26 years (1991–2016). Antimicrobial resistance (AMR) testing was performed for most common clinical agents. Whole-genome sequencing and SNP-level analysis was conducted. Comparative genomics of Vellore isolates was performed to infer transmission and AMR events. Results We identified multidrug-resistance (MDR)–associated clade 4.3.1 as the dominant genotype. We detected 4.3.1 S. Typhi as early as 1991, the earliest to be reported form India, and the majority were fluoroquinolone resistant and not MDR. MDR was not detected at all in other genotypes circulating in Vellore. Comparison with global S. Typhi showed 2 Vellore subgroups (I and II) that were phylogenetically highly related to previously described South Asia (subgroup I, II) and Southeast Asia (subgroup II) clades. Conclusions 4.3.1 S. Typhi has dominated in Vellore for 2 decades. Our study would assist public health agencies in better tracking of transmission and persistence of this successful clade in India and globally. It informs clinicians of the AMR pattern of circulating clone, which would add confidence to their prophylactic/treatment decision making and facilitate efficient patient care.
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Affiliation(s)
- Agila Kumari Pragasam
- Department of Clinical Microbiology, Christian Medical College, Vellore, India.,Department of Medicine, Univesity of Cambridge, Cambridge, United Kingdom
| | - Derek Pickard
- Department of Medicine, Univesity of Cambridge, Cambridge, United Kingdom
| | - Vanessa Wong
- Department of Medicine, Univesity of Cambridge, Cambridge, United Kingdom
| | - Gordon Dougan
- Department of Medicine, Univesity of Cambridge, Cambridge, United Kingdom.,Wellcome Sanger Institute, Hinxton, United Kingdom
| | - Gagandeep Kang
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
| | - Andrew Thompson
- Department of Medicine, Univesity of Cambridge, Cambridge, United Kingdom
| | - Jacob John
- Department of Clinical Microbiology, Christian Medical College, Vellore, India
| | | | - Ankur Mutreja
- Department of Medicine, Univesity of Cambridge, Cambridge, United Kingdom.,Wellcome Sanger Institute, Hinxton, United Kingdom
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13
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Manesh A, Meltzer E, Jin C, Britto C, Deodhar D, Radha S, Schwartz E, Rupali P. Typhoid and paratyphoid fever: a clinical seminar. J Travel Med 2021; 28:6129661. [PMID: 33550411 DOI: 10.1093/jtm/taab012] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Revised: 01/07/2021] [Indexed: 01/06/2023]
Abstract
Rationale for review: Enteric fever (EF) caused by Salmonella enterica subspecies enterica serovar Typhi (Salmonella Typhi) and S. Paratyphi (Salmonella Paratyphi) remains an important cause of infectious morbidity and mortality in many low-income countries and, therefore, still poses a major infectious risk for travellers to endemic countries. Main findings: Although the global burden of EF has decreased over the past two decades, prevalence of EF remains high in Asia and Africa, with the highest prevalence reported from the Indian subcontinent. These statistics are mirrored by data on travel-related EF. Widespread and increasing antimicrobial resistance has narrowed treatment options for travel-related EF. Ceftriaxone- and azithromycin-based therapies are commonly used, even with the emergence of extremely drug-resistant typhoid in Pakistan. Preventive measures among locals and travellers include provision of safe food and water and vaccination. Food and water precautions offer limited protection, and the efficacy of Salmonella Typhi vaccines is only moderate signifying the need for travellers to be extra cautious. Recommendations: Improvement in the diagnosis of typhoid with high degree of clinical suspicion, better diagnostic assays, early and accurate detection of resistance, therapy with appropriate drugs, improvements in hygiene and sanitation with provision of safe drinking water in endemic areas and vaccination among travellers as well as in the endemic population are keys to controlling typhoid. While typhoid vaccines are recommended for travellers to high-risk areas, moderate efficacy and inability to protect against Salmonella Paratyphi are limitations to bear in mind. Improved Salmonella Typhi vaccines and vaccines against Salmonella Paratyphi A are required.
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Affiliation(s)
- Abi Manesh
- Department of Infectious Diseases, Christian Medical College, Vellore, India
| | - Eyal Meltzer
- Department of Medicine `C', Center for Geographic Medicine, Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Celina Jin
- Oxford Vaccine Group, Department of Pediatrics, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Carl Britto
- Oxford Vaccine Group, Department of Pediatrics, NIHR Oxford Biomedical Research Centre, University of Oxford, Oxford, UK
| | - Divya Deodhar
- Department of Infectious Diseases, Christian Medical College, Vellore, India
| | - Sneha Radha
- Department of Infectious Diseases, Christian Medical College, Vellore, India
| | - Eli Schwartz
- Department of Medicine `C', Center for Geographic Medicine, Sheba Medical Center, Tel-Hashomer, Israel.,Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Priscilla Rupali
- Department of Infectious Diseases, Christian Medical College, Vellore, India
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14
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Salmonella Paratyphi A Outer Membrane Vesicles Displaying Vi Polysaccharide as a Multivalent Vaccine against Enteric Fever. Infect Immun 2021; 89:IAI.00699-20. [PMID: 33318138 DOI: 10.1128/iai.00699-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2020] [Accepted: 12/07/2020] [Indexed: 12/23/2022] Open
Abstract
Typhoid and paratyphoid fevers have a high incidence worldwide and coexist in many geographical areas, especially in low-middle-income countries (LMIC) in South and Southeast Asia. There is extensive consensus on the urgent need for better and affordable vaccines against systemic Salmonella infections. Generalized modules for membrane antigens (GMMA), outer membrane exosomes shed by Salmonella bacteria genetically manipulated to increase blebbing, resemble the bacterial surface where protective antigens are displayed in their native environment. Here, we engineered S Paratyphi A using the pDC5-viaB plasmid to generate GMMA displaying the heterologous S Typhi Vi antigen together with the homologous O:2 O antigen. The presence of both Vi and O:2 was confirmed by flow cytometry on bacterial cells, and their amount was quantified on the resulting vesicles through a panel of analytical methods. When tested in mice, such GMMA induced a strong antibody response against both Vi and O:2, and these antibodies were functional in a serum bactericidal assay. Our approach yielded a bivalent vaccine candidate able to induce immune responses against different Salmonella serovars, which could benefit LMIC residents and travelers.
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15
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Otten T, de Mast Q, Koeneman B, Althaus T, Lubell Y, van der Ven A. Value of C-reactive protein in differentiating viral from bacterial aetiologies in patients with non-malaria acute undifferentiated fever in tropical areas: a meta-analysis and individual patient data study. Trans R Soc Trop Med Hyg 2021; 115:1130-1143. [PMID: 33644814 DOI: 10.1093/trstmh/traa186] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2020] [Revised: 11/23/2020] [Accepted: 12/22/2020] [Indexed: 12/21/2022] Open
Abstract
C-reactive protein (CRP) is used to discriminate common bacterial and viral infections, but its utility in tropical settings remains unknown. We performed a meta-analysis of studies performed in Asia and Africa. First, mean CRP levels for specific tropical infections were calculated. Thereafter, individual patient data (IPD) from patients with non-malarial undifferentiated fever (NMUF) who were tested for viral and bacterial pathogens were analysed, calculating separate cut-off values and their performance in classifying viral or bacterial disease. Mean CRP levels of 7307 patients from 13 countries were dengue 12.0 mg/l (standard error [SE] 2.7), chikungunya 41.0 mg/l (SE 19.5), influenza 15.9 mg/l (SE 6.3), Crimean-Congo haemorrhagic fever 9.7 mg/l (SE 4.7), Salmonella 61.9 mg/l (SE 5.4), Rickettsia 61.3 mg/l (SE 8.8), Coxiella burnetii 98.7 mg/l (SE 44.0) and Leptospira infections 113.8 mg/l (SE 23.1). IPD analysis of 1059 NMUF patients ≥5 y of age showed CRP <10 mg/l had 52% sensitivity (95% confidence interval [CI] 48 to 56) and 95% specificity (95% CI 93 to 97) to detect viral infections. CRP >40 mg/l had 74% sensitivity (95% CI 70 to 77) and 84% specificity (95% CI 81 to 87) to identify bacterial infections. Compared with routine care, the relative risk for incorrect classification was 0.64 (95% CI 0.55 to 0.75) and the number needed to test for one extra correctly classified case was 8 (95% CI 6 to 12). A two cut-off value CRP test may help clinicians to discriminate viral and bacterial aetiologies of NMUF in tropical areas.
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Affiliation(s)
- Twan Otten
- Department of International Health and Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Quirijn de Mast
- Department of International Health and Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Bouke Koeneman
- Department of International Health and Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands
| | - Thomas Althaus
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - Yoel Lubell
- Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, 10400, Thailand
| | - André van der Ven
- Department of International Health and Infectious Diseases, Radboud University Medical Centre, Nijmegen, The Netherlands
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16
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Sajib MSI, Tanmoy AM, Hooda Y, Rahman H, Andrews JR, Garrett DO, Endtz HP, Saha SK, Saha S. Tracking the Emergence of Azithromycin Resistance in Multiple Genotypes of Typhoidal Salmonella. mBio 2021; 12:e03481-20. [PMID: 33593966 PMCID: PMC8545119 DOI: 10.1128/mbio.03481-20] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Accepted: 01/05/2021] [Indexed: 11/29/2022] Open
Abstract
The rising prevalence of antimicrobial resistance in Salmonella enterica serovars Typhi and Paratyphi A, causative agents of typhoid and paratyphoid, have led to fears of untreatable infections. Of specific concern is the emerging resistance against azithromycin, the only remaining oral drug to treat extensively drug resistant (XDR) typhoid. Since the first report of azithromycin resistance from Bangladesh in 2019, cases have been reported from Nepal, India, and Pakistan. The genetic basis of this resistance is a single point mutation in the efflux pump AcrB (R717Q/L). Here, we report 38 additional cases of azithromycin-resistant (AzmR) Salmonella Typhi and Paratyphi A isolated in Bangladesh between 2016 and 2018. Using genomic analysis of 56 AzmR isolates from South Asia with AcrB-R717Q/L, we confirm that this mutation has spontaneously emerged in different Salmonella Typhi and Paratyphi A genotypes. The largest cluster of AzmR Typhi belonged to genotype 4.3.1.1; Bayesian analysis predicts the mutation to have emerged sometime in 2010. A travel-related Typhi isolate with AcrB-R717Q belonging to 4.3.1.1 was isolated in the United Kingdom, increasing fears of global spread. For real-time detection of AcrB-R717Q/L, we developed an extraction-free, rapid, and low-cost mismatch amplification mutation assay (MAMA). Validation of MAMA using 113 AzmR and non-AzmR isolates yielded >98% specificity and sensitivity versus phenotypic and whole-genome sequencing assays currently used for azithromycin resistance detection. With increasing azithromycin use, AcrB-R717Q/L is likely to be acquired by XDR strains. The proposed tool for active detection and surveillance of this mutation may detect pan-oral drug resistance early, giving us a window to intervene.IMPORTANCE In the early 1900s, with mortality of ∼30%, typhoid and paratyphoid ravaged parts of the world; with improved water, sanitation, and hygiene in resource-rich countries and the advent of antimicrobials, mortality dwindled to <1%. Today, the burden rests disproportionately on South Asia, where the primary means for combatting the disease is antimicrobials. However, prevalence of antimicrobial resistance is rising and, in 2016, an extensively drug resistant Typhi strain triggered an ongoing outbreak in Pakistan, leaving only one oral drug, azithromycin, to treat it. Since the description of emergence of azithromycin resistance, conferred by a point mutation in acrB (AcrB-R717Q/L) in 2019, there have been increasing numbers of reports. Using genomics and Bayesian analysis, we illustrate that this mutation emerged in approximately 2010 and has spontaneously arisen multiple times. Emergence of pan-oral drug resistant Salmonella Typhi is imminent. We developed a low-cost, rapid PCR tool to facilitate real-time detection and prevention policies.
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Affiliation(s)
- Mohammad S I Sajib
- Child Health Research Foundation, Dhaka, Bangladesh
- Institute of Biodiversity, Animal Health, and Comparative Medicine, University of Glasgow, Glasgow, United Kingdom
| | - Arif M Tanmoy
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Yogesh Hooda
- Child Health Research Foundation, Dhaka, Bangladesh
- MRC-Laboratory Molecular Biology, Cambridge, United Kingdom
| | | | - Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | | | - Hubert P Endtz
- Department of Medical Microbiology and Infectious Diseases, Erasmus University Medical Center, Rotterdam, The Netherlands
- Fondation Mérieux and Centre International de Recherche en Infectiologie, INSERM, Lyon, France
| | - Samir K Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
- Bangladesh Institute of Child Health, Dhaka, Bangladesh
| | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh
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17
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Gibani MM, Jin C, Shrestha S, Moore M, Norman L, Voysey M, Jones E, Blackwell L, Thomaides-Brears H, Hill J, Blohmke CJ, Dobinson HC, Baker P, Jones C, Campbell D, Mujadidi YF, Plested E, Preciado-Llanes L, Napolitani G, Simmons A, Gordon MA, Angus B, Darton TC, Cerundulo V, Pollard AJ. Homologous and heterologous re-challenge with Salmonella Typhi and Salmonella Paratyphi A in a randomised controlled human infection model. PLoS Negl Trop Dis 2020; 14:e0008783. [PMID: 33079959 PMCID: PMC7598925 DOI: 10.1371/journal.pntd.0008783] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 10/30/2020] [Accepted: 09/08/2020] [Indexed: 11/19/2022] Open
Abstract
Enteric fever is a systemic infection caused by Salmonella Typhi or Paratyphi A. In many endemic areas, these serovars co-circulate and can cause multiple infection-episodes in childhood. Prior exposure is thought to confer partial, but incomplete, protection against subsequent attacks of enteric fever. Empirical data to support this hypothesis are limited, and there are few studies describing the occurrence of heterologous-protection between these closely related serovars. We performed a challenge-re-challenge study using a controlled human infection model (CHIM) to investigate the extent of infection-derived immunity to Salmonella Typhi or Paratyphi A infection. We recruited healthy volunteers into two groups: naïve volunteers with no prior exposure to Salmonella Typhi/Paratyphi A and volunteers previously-exposed to Salmonella Typhi or Paratyphi A in earlier CHIM studies. Within each group, participants were randomised 1:1 to oral challenge with either Salmonella Typhi (104 CFU) or Paratyphi A (103 CFU). The primary objective was to compare the attack rate between naïve and previously challenged individuals, defined as the proportion of participants per group meeting the diagnostic criteria of temperature of ≥38°C persisting for ≥12 hours and/or S. Typhi/Paratyphi bacteraemia up to day 14 post challenge. The attack-rate in participants who underwent homologous re-challenge with Salmonella Typhi was reduced compared with challenged naïve controls, although this reduction was not statistically significant (12/27[44%] vs. 12/19[63%]; Relative risk 0.70; 95% CI 0.41-1.21; p = 0.24). Homologous re-challenge with Salmonella Paratyphi A also resulted in a lower attack-rate than was seen in challenged naïve controls (3/12[25%] vs. 10/18[56%]; RR0.45; 95% CI 0.16-1.30; p = 0.14). Evidence of protection was supported by a post hoc analysis in which previous exposure was associated with an approximately 36% and 57% reduced risk of typhoid or paratyphoid disease respectively on re-challenge. Individuals who did not develop enteric fever on primary exposure were significantly more likely to be protected on re-challenge, compared with individuals who developed disease on primary exposure. Heterologous re-challenge with Salmonella Typhi or Salmonella Paratyphi A was not associated with a reduced attack rate following challenge. Within the context of the model, prior exposure was not associated with reduced disease severity, altered microbiological profile or boosting of humoral immune responses. We conclude that prior Salmonella Typhi and Paratyphi A exposure may confer partial but incomplete protection against subsequent infection, but with a comparable clinical and microbiological phenotype. There is no demonstrable cross-protection between these serovars, consistent with the co-circulation of Salmonella Typhi and Paratyphi A. Collectively, these data are consistent with surveillance and modelling studies that indicate multiple infections can occur in high transmission settings, supporting the need for vaccines to reduce the burden of disease in childhood and achieve disease control. Trial registration NCT02192008; clinicaltrials.gov.
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Affiliation(s)
- Malick M. Gibani
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
- Department of Infectious Diseases, Imperial College London, United Kingdom
| | - Celina Jin
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Sonu Shrestha
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Maria Moore
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Lily Norman
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Merryn Voysey
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Elizabeth Jones
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Luke Blackwell
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Helena Thomaides-Brears
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Jennifer Hill
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Christoph J. Blohmke
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Hazel C. Dobinson
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Philip Baker
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Claire Jones
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Danielle Campbell
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Yama F. Mujadidi
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Emma Plested
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
| | - Lorena Preciado-Llanes
- Institute for Infection and Global Health, University of Liverpool, United Kingdom
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, University of Oxford, United Kingdom
| | - Giorgio Napolitani
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, University of Oxford, United Kingdom
| | - Alison Simmons
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, University of Oxford, United Kingdom
| | - Melita A. Gordon
- Institute for Infection and Global Health, University of Liverpool, United Kingdom
- Malawi-Liverpool-Wellcome Trust Clinical Research Programme, Blantyre, Malawi
| | - Brian Angus
- Nuffield Department of Medicine, University of Oxford, United Kingdom
| | - Thomas C. Darton
- Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield, United Kingdom
| | - Vincenzo Cerundulo
- Medical Research Council Human Immunology Unit, Radcliffe Department of Medicine, University of Oxford, United Kingdom
| | - Andrew J. Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford and the NIHR Oxford Biomedical Research Centre, United Kingdom
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18
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Gandra S, Alvarez-Uria G, Turner P, Joshi J, Limmathurotsakul D, van Doorn HR. Antimicrobial Resistance Surveillance in Low- and Middle-Income Countries: Progress and Challenges in Eight South Asian and Southeast Asian Countries. Clin Microbiol Rev 2020; 33:e00048-19. [PMID: 32522747 PMCID: PMC7289787 DOI: 10.1128/cmr.00048-19] [Citation(s) in RCA: 94] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
Antimicrobial resistance (AMR) is a serious global health threat and is predicted to cause significant health and economic impacts, particularly in low- and middle-income countries (LMICs). AMR surveillance is critical in LMICs due to high burden of bacterial infections; however, conducting AMR surveillance in resource-limited settings is constrained by poorly functioning health systems, scarce financial resources, and lack of skilled personnel. In 2015, the United Nations World Health Assembly endorsed the World Health Organization's Global Action Plan to tackle AMR; thus, several countries are striving to improve their AMR surveillance capacity, including making significant investments and establishing and expanding surveillance networks. Initial data generated from AMR surveillance networks in LMICs suggest the high prevalence of resistance, but these data exhibit several shortcomings, such as a lack of representativeness, lack of standardized laboratory practices, and underutilization of microbiology services. Despite significant progress, AMR surveillance networks in LMICs face several challenges in expansion and sustainability due to limited financial resources and technical capacity. This review summarizes the existing health infrastructure affecting the establishment of AMR surveillance programs, the burden of bacterial infections demonstrating the need for AMR surveillance, and current progress and challenges in AMR surveillance efforts in eight South and Southeast Asian countries.
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Affiliation(s)
- Sumanth Gandra
- Division of Infectious Diseases, Department of Internal Medicine, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Gerardo Alvarez-Uria
- Department of Infectious Diseases, Rural Development Trust Hospital, Bathalapalli, Anantapur, Andhra Pradesh, India
| | - Paul Turner
- Cambodia Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
| | - Jyoti Joshi
- Center for Disease Dynamics, Economics and Policy, New Delhi, India
| | - Direk Limmathurotsakul
- 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
| | - H Rogier van Doorn
- Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom
- Oxford University Clinical Research Unit, National Hospital for Tropical Diseases, Hanoi, Vietnam
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19
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Rozo M, Schully KL, Philipson C, Fitkariwala A, Nhim D, Som T, Sieng D, Huot B, Dul S, Gregory MJ, Heang V, Vaughn A, Vantha T, Prouty AM, Chao CC, Zhang Z, Belinskaya T, Voegtly LJ, Cer RZ, Bishop-Lilly KA, Duplessis C, Lawler JV, Clark DV. An Observational Study of Sepsis in Takeo Province Cambodia: An in-depth examination of pathogens causing severe infections. PLoS Negl Trop Dis 2020; 14:e0008381. [PMID: 32804954 PMCID: PMC7430706 DOI: 10.1371/journal.pntd.0008381] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Accepted: 05/11/2020] [Indexed: 01/20/2023] Open
Abstract
The world's most consequential pathogens occur in regions with the fewest diagnostic resources, leaving the true burden of these diseases largely under-represented. During a prospective observational study of sepsis in Takeo Province Cambodia, we enrolled 200 patients over an 18-month period. By coupling traditional diagnostic methods such as culture, serology, and PCR to Next Generation Sequencing (NGS) and advanced statistical analyses, we successfully identified a pathogenic cause in 46.5% of our cohort. In all, we detected 25 infectious agents in 93 patients, including severe threat pathogens such as Burkholderia pseudomallei and viral pathogens such as Dengue virus. Approximately half of our cohort remained undiagnosed; however, an independent panel of clinical adjudicators determined that 81% of those patients had infectious causes of their hospitalization, further underscoring the difficulty of diagnosing severe infections in resource-limited settings. We garnered greater insight as to the clinical features of severe infection in Cambodia through analysis of a robust set of clinical data.
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Affiliation(s)
- Michelle Rozo
- Austere environments Consortium for Enhanced Sepsis Outcomes (ACESO), Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Ft. Detrick, Maryland, United States of America
- The Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, United States of America
| | - Kevin L. Schully
- Austere environments Consortium for Enhanced Sepsis Outcomes (ACESO), Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Ft. Detrick, Maryland, United States of America
| | - Casandra Philipson
- Genomics and Bioinformatics Department, Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Fort Detrick, Maryland, United States of America
- Defense Threat Reduction Agency, Fort Belvoir, Virginia, United States of America
| | | | | | - Tin Som
- Chenda Polyclinic, Phnom Penh, Cambodia
| | - Darith Sieng
- Lucerent Clinical Solutions, Phnom Penh, Cambodia
| | - Bora Huot
- Chenda Polyclinic, Phnom Penh, Cambodia
| | - Sokha Dul
- Chenda Polyclinic, Phnom Penh, Cambodia
| | | | - Vireak Heang
- U.S. Naval Medical Research Unit TWO (NAMRU-2), Phnom Penh, Cambodia
| | - Andrew Vaughn
- U.S. Naval Medical Research Unit TWO (NAMRU-2), Phnom Penh, Cambodia
| | - Te Vantha
- Takeo Provincial Referral Hospital, Takeo, Cambodia
| | - Angela M. Prouty
- U.S. Naval Medical Research Unit TWO (NAMRU-2), Phnom Penh, Cambodia
| | - Chien-Chung Chao
- Viral and Rickettsial Diseases Department, Naval Medical Research Center-Silver Spring, Silver Spring, Maryland, United States of America
| | - Zhiwen Zhang
- Viral and Rickettsial Diseases Department, Naval Medical Research Center-Silver Spring, Silver Spring, Maryland, United States of America
| | - Tatyana Belinskaya
- Viral and Rickettsial Diseases Department, Naval Medical Research Center-Silver Spring, Silver Spring, Maryland, United States of America
| | - Logan J. Voegtly
- Genomics and Bioinformatics Department, Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Fort Detrick, Maryland, United States of America
- Leidos, Reston, Virginia, United States of America
| | - Regina Z. Cer
- Genomics and Bioinformatics Department, Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Fort Detrick, Maryland, United States of America
- Leidos, Reston, Virginia, United States of America
| | - Kimberly A. Bishop-Lilly
- Genomics and Bioinformatics Department, Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Fort Detrick, Maryland, United States of America
| | - Chris Duplessis
- Austere environments Consortium for Enhanced Sepsis Outcomes (ACESO), Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Ft. Detrick, Maryland, United States of America
| | - James V. Lawler
- Austere environments Consortium for Enhanced Sepsis Outcomes (ACESO), Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Ft. Detrick, Maryland, United States of America
- Global Center for Health Security at Nebraska and Division of Infectious Disease, Department of Internal Medicine, University of Nebraska Medical Center, Omaha, NE, United States of America
| | - Danielle V. Clark
- Austere environments Consortium for Enhanced Sepsis Outcomes (ACESO), Biological Defense Research Directorate, Naval Medical Research Center-Frederick, Ft. Detrick, Maryland, United States of America
- The Henry M Jackson Foundation for the Advancement of Military Medicine, Bethesda, Maryland, United States of America
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20
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Jones G, Pardos de la Gandara M, Herrera-Leon L, Herrera-Leon S, Varela Martinez C, Hureaux-Roy R, Abdallah Y, Nisavanh A, Fabre L, Renaudat C, Mossong J, Mattheus W, Huard C, Le Borgne C, de Valk H, Weill FX, Jourdan-Da Silva N. Outbreak of Salmonella enterica serotype Poona in infants linked to persistent Salmonella contamination in an infant formula manufacturing facility, France, August 2018 to February 2019. ACTA ACUST UNITED AC 2020; 24. [PMID: 30940315 PMCID: PMC6446512 DOI: 10.2807/1560-7917.es.2019.24.13.1900161] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We describe a Salmonella Poona outbreak involving 31 infant cases in France. Following outbreak detection on 18 January 2019, consumption of rice-based infant formula manufactured at a facility in Spain was identified as the probable cause, leading to a recall on 24 January. Whole genome sequencing analysis linked present outbreak isolates to a 2010–11 S. Poona outbreak in Spain associated with formula manufactured in the same facility, indicating a persistent source of contamination.
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Affiliation(s)
| | - Maria Pardos de la Gandara
- Centre National de Référence des Escherichia coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Laura Herrera-Leon
- National Centre for Microbiology, CIBER Epidemiologia y Salud Publica, Instituto de Salud Carlos III, Madrid, Spain
| | - Silvia Herrera-Leon
- National Centre for Microbiology, CIBER Epidemiologia y Salud Publica, Instituto de Salud Carlos III, Madrid, Spain
| | - Carmen Varela Martinez
- National Centre for Epidemiology, CIBER Epidemiologia y Salud Publica, Instituto de Salud Carlos III, Madrid, Spain
| | - Roselyne Hureaux-Roy
- Directorate of the Ministry of Economy in charge of consumers' affairs, Paris, France
| | - Yasmine Abdallah
- Directorate of the Ministry of Economy in charge of consumers' affairs, Paris, France
| | | | - Laetitia Fabre
- Centre National de Référence des Escherichia coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Charlotte Renaudat
- Centre National de Référence des Escherichia coli, Shigella et Salmonella, Institut Pasteur, Paris, France
| | - Joël Mossong
- Department of Microbiology, Laboratoire National de Santé, Dudelange, Luxembourg
| | - Wesley Mattheus
- National Reference Centre for Salmonella and Shigella, Sciensano, Brussels, Belgium
| | - Cécile Huard
- Direction Santé et Aide aux Personnes, Commission Communautaire Commune, Brussels, Belgium
| | | | | | - François-Xavier Weill
- Centre National de Référence des Escherichia coli, Shigella et Salmonella, Institut Pasteur, Paris, France
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21
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Roberts T, Rattanavong S, Phommasone K, Chansamouth V, Davong V, Keoluangkhot V, Hongsakhone S, Bounsavath N, Mayxay M, Vongsouvath M, Dance DAB, Newton PN. Typhoid in Laos: An 18-Year Perspective. Am J Trop Med Hyg 2020; 102:749. [PMID: 31989918 PMCID: PMC7124924 DOI: 10.4269/ajtmh.19-0637] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Although typhoid is endemic to Southeast Asia, very little is known about the disease in Laos. Typhoid vaccination is not included in the national immunization program. Although sanitation has improved, one million people still do not have access to basic clean water sources. We describe the epidemiology and antimicrobial susceptibility patterns of Salmonella enterica serovar Typhi (S. Typhi) infection in Laos based on isolates accrued over 18 years at Mahosot Hospital, Vientiane. All blood cultures collected from patients presenting with fever submitted to the Microbiology Laboratory at Mahosot Hospital (February 2000–December 2018) were included. This included patients from Vientiane and four provincial hospitals and one typhoid outbreak investigation. A total of 913 (1.5%) of 60,384 blood cultures were positive for S. Typhi. The majority of isolates with data available (712/898, 79.3%) were susceptible to all antibiotics tested, with 59 (6.5%) multidrug-resistant (MDR) isolates, mostly from one outbreak. Of 854 isolates, 12 (1.4%) were fluoroquinolone resistant. Patient admissions peaked between March and June at the end of the dry season. Although there are key limitations, these data give the first detailed epidemiological evidence of typhoid in Laos. However, estimates will be greatly influenced by access to blood culture services and health-seeking behavior. Although typhoid multidrug resistance and fluoroquinolone resistance are not currently major issues in Laos, continued surveillance and improved antibiotic stewardship are necessary to forestall worsening of the situation. Cost-effectiveness analysis is needed to inform decisions regarding typhoid vaccine introduction.
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Affiliation(s)
- Tamalee Roberts
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Sayaphet Rattanavong
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Koukeo Phommasone
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Vilada Chansamouth
- Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Viengmon Davong
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Valy Keoluangkhot
- Adult Infectious Diseases Ward, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Sitthivone Hongsakhone
- Oudomxay Provincial Health Department, Oudomxay, Lao People's Democratic Republic.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Naly Bounsavath
- Huaphan Provincial Health Department, Huaphan, Lao People's Democratic Republic.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Mayfong Mayxay
- Institute of Research and Education Development, University of Health Sciences, Vientiane, Lao People's Democratic Republic.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Manivanh Vongsouvath
- Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - David A B Dance
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
| | - Paul N Newton
- Faculty of Infectious and Tropical Diseases, London School of Hygiene and Tropical Medicine, London, United Kingdom.,Nuffield Department of Medicine, Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, United Kingdom.,Lao-Oxford-Mahosot Hospital-Wellcome Trust Research Unit, Microbiology Laboratory, Mahosot Hospital, Vientiane, Lao People's Democratic Republic
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22
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Kheng C, Meas V, Pen S, Sar P, Turner P. Salmonella Typhi and Paratyphi A infections in Cambodian children, 2012-2016. Int J Infect Dis 2020; 97:334-336. [PMID: 32569838 DOI: 10.1016/j.ijid.2020.06.054] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Revised: 06/14/2020] [Accepted: 06/15/2020] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES Enteric fever remains an important diagnostic and treatment challenge in febrile children living in the tropics. In the context of a national Salmonella enterica serovar Paratyphi A outbreak, the objective of this retrospective study was to compare features of S. Typhi and S. Paratyphi A infections in Cambodian children. METHODS Clinical and laboratory features were reviewed for 192 blood culture-confirmed children with S. Typhi and S. Paratyphi A infections presenting to a paediatric referral hospital in Siem Reap, 2012-2016. RESULTS Children with S. Typhi infections were younger, were more likely to have chills and/or diarrhoea, and were more frequently hospitalized than those with S. Paratyphi A infections. Over three quarters (88.3%) of S. Typhi isolates were multidrug-resistant, compared to none of the S. Paratyphi A. CONCLUSIONS In this small study of Cambodian children, S. Typhi infections were more severe than S. Paratyphi A infections. Antibiotic resistance limits treatment options for enteric fever in this population.
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Affiliation(s)
- Chheng Kheng
- Angkor Hospital for Children, Siem Reap, Cambodia
| | - Vorlark Meas
- Angkor Hospital for Children, Siem Reap, Cambodia
| | - Sotheavy Pen
- Angkor Hospital for Children, Siem Reap, Cambodia
| | - Poda Sar
- Cambodia Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - Paul Turner
- Cambodia Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia; Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, United Kingdom.
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23
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Abstract
Multiple drug (antibiotic) resistance (MDR) has become a major threat to the treatment of typhoid and other infectious diseases. Since the 1970s, this threat has increased in Salmonella enterica serovar Typhi, driven in part by the emergence of successful genetic clades, such as haplotype H58, associated with the MDR phenotype. H58 S. Typhi can express multiple antibiotic resistance determinants while retaining the ability to efficiently transmit and persist within the human population. The recent identification of extensively drug resistant S. Typhi only highlights the dangers of ignoring this threat. Here we discuss the evolution of the S. Typhi MDR phenotype and consider options for management.
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Affiliation(s)
- Zoe A Dyson
- Department of Medicine, University of Cambridge, Hinxton, Cambridge, United Kingdom
| | - Elizabeth J Klemm
- Department of Medicine, University of Cambridge, Hinxton, Cambridge, United Kingdom.,Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
| | - Sophie Palmer
- Department of Medicine, University of Cambridge, Hinxton, Cambridge, United Kingdom
| | - Gordon Dougan
- Department of Medicine, University of Cambridge, Hinxton, Cambridge, United Kingdom.,Wellcome Sanger Institute, Wellcome Genome Campus, Hinxton, Cambridge, United Kingdom
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24
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Castellanos LR, van der Graaf-van Bloois L, Donado-Godoy P, Veldman K, Duarte F, Acuña MT, Jarquín C, Weill FX, Mevius DJ, Wagenaar JA, Hordijk J, Zomer AL. Antimicrobial Resistance in Salmonella enterica Serovar Paratyphi B Variant Java in Poultry from Europe and Latin America. Emerg Infect Dis 2020; 26:1164-1173. [PMID: 32441616 PMCID: PMC7258445 DOI: 10.3201/eid2606.191121] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
Salmonella enterica serovar Paratyphi B variant Java sequence type 28 is prevalent in poultry and poultry meat. We investigated the evolutionary relatedness between sequence type 28 strains from Europe and Latin America using time-resolved phylogeny and principal component analysis. We sequenced isolates from Colombia, Guatemala, Costa Rica, and the Netherlands and complemented them with publicly available genomes from Europe, Africa, and the Middle East. Phylogenetic time trees and effective population sizes (Ne) showed separate clustering of strains from Latin America and Europe. The separation is estimated to have occurred during the 1980s. Ne of strains increased sharply in Europe around 1995 and in Latin America around 2005. Principal component analysis on noncore genes showed a clear distinction between strains from Europe and Latin America, whereas the plasmid gene content was similar. Regardless of the evolutionary separation, similar features of resistance to β-lactams and quinolones/fluoroquinolones indicated parallel evolution of antimicrobial resistance in both regions.
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25
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Nadimpalli M, Fabre L, Yith V, Sem N, Gouali M, Delarocque-Astagneau E, Sreng N, Le Hello S. CTX-M-55-type ESBL-producing Salmonella enterica are emerging among retail meats in Phnom Penh, Cambodia. J Antimicrob Chemother 2020; 74:342-348. [PMID: 30376113 DOI: 10.1093/jac/dky451] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Accepted: 10/07/2018] [Indexed: 11/13/2022] Open
Abstract
Background Salmonella enterica is a leading cause of human gastroenteritis. S. enterica strains that produce ESBLs (ESBL-Salm) remain rare in Europe and North America, but less is known about their prevalence among animal-derived foods in countries with weaker food safety practices and unregulated veterinary antibiotic use. Objectives To examine the prevalence and characteristics of ESBL-Salm from retail meats in Phnom Penh, Cambodia. Methods We tested fish, pork and chicken from two markets for ESBL- and carbapenemase-producing Salmonella from September-December 2016, using cefotaxime- and ertapenem-supplemented media, respectively. ESBL-Salm were sequenced and their genomes characterized. We performed plasmid conjugation experiments to assess the co-transferability of ESBL-encoding genes and MDR phenotypes. Results Twenty-six of 150 fish and meat samples (17%) were positive for ESBL-Salm, including 10/60 fish (17%), 15/60 pork (25%) and 1/30 chicken (3%). Carbapenemase-producing Salmonella strains were not detected. Pork-origin ESBL-Salm were primarily serotypes Rissen (10/15) or a monophasic variant of Typhimurium 4,5,12:i:- (3/15), whereas Saintpaul (3/10) and Newport (4/10) were more common among fish. Most ESBL enzymes were encoded by blaCTX-M-55 genes (24/26) harboured on conjugative IncA/C2 (n = 14) or IncHI2 (n = 10) plasmids. Resistance to up to six additional drug classes was co-transferred by each plasmid type. ESBL-Salm were resistant to almost every antibiotic recommended for severe salmonellosis treatment. Conclusions CTX-M-55-type S. enterica are highly prevalent among pork and fish from Phnom Penh markets and their spread appears to be mediated by MDR IncA/C2 and IncHI2 plasmids. Food safety must be improved and veterinary antibiotic use should be regulated to protect public health.
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Affiliation(s)
- Maya Nadimpalli
- Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases Unit (B2PHI), Inserm, Université de Versailles Saint-Quentin-en-Yvelines, Institut Pasteur, Université Paris-Saclay, 25 rue du Docteur Roux, Paris, France
| | - Laetitia Fabre
- Enteric Bacterial Pathogens Unit, Institut Pasteur, 25 rue du Docteur Roux, Paris, France
| | - Vuthy Yith
- Laboratory of Environment and Food Safety, Institut Pasteur du Cambodge, 5 Preah Monivong Blvd, Phnom Penh, Cambodia
| | - Nita Sem
- Laboratory of Environment and Food Safety, Institut Pasteur du Cambodge, 5 Preah Monivong Blvd, Phnom Penh, Cambodia
| | - Malika Gouali
- Laboratory of Environment and Food Safety, Institut Pasteur du Cambodge, 5 Preah Monivong Blvd, Phnom Penh, Cambodia
| | - Elisabeth Delarocque-Astagneau
- Biostatistics, Biomathematics, Pharmacoepidemiology and Infectious Diseases Unit (B2PHI), Inserm, Université de Versailles Saint-Quentin-en-Yvelines, Institut Pasteur, Université Paris-Saclay, 25 rue du Docteur Roux, Paris, France.,Assistance Publique/Hôpitaux de Paris, Raymond-Poincaré Hospital, 104 Boulevard Raymond Poincaré, Garches, France
| | - Navin Sreng
- Laboratory of Environment and Food Safety, Institut Pasteur du Cambodge, 5 Preah Monivong Blvd, Phnom Penh, Cambodia
| | - Simon Le Hello
- Enteric Bacterial Pathogens Unit, Institut Pasteur, 25 rue du Docteur Roux, Paris, France
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Clinico-Bacteriological Profile of Typhoid Fever in a Private Sector Hospital in New Delhi. Indian Pediatr 2019. [DOI: 10.1007/s13312-019-1686-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Acheampong G, Owusu M, Owusu-Ofori A, Osei I, Sarpong N, Sylverken A, Kung HJ, Cho ST, Kuo CH, Park SE, Marks F, Adu-Sarkodie Y, Owusu-Dabo E. Chromosomal and plasmid-mediated fluoroquinolone resistance in human Salmonella enterica infection in Ghana. BMC Infect Dis 2019; 19:898. [PMID: 31660876 PMCID: PMC6819380 DOI: 10.1186/s12879-019-4522-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 09/30/2019] [Indexed: 11/19/2022] Open
Abstract
Background Salmonella infection poses significant public health threat globally, especially in resource-limited countries. Emergence and spread of antibiotic resistant strains to fluoroquinolones have led to treatment failures and increased mortality in Salmonella infection. However, there is dearth of information regarding mechanisms of resistance to fluoroquinolones in Ghana. This study therefore sought to identify chromosomal mutations and plasmid-mediated resistance as possible mechanisms of fluoroquinolone resistance from clinical isolates in Ghana. Methods This was a retrospective study of archived isolates biobanked at Kumasi Centre for Collaborative Research in Tropical Medicine, Ghana. Isolates were obtained from blood, stool and oropharynx samples at two hospitals, between May, 2016 and January, 2018. Salmonella identification was done using standard microbiological protocols and antibiotic susceptibility testing performed by Kirby-Bauer disc diffusion method. Isolates with intermediate susceptibility and/or resistance to nalidixic acid and/or ciprofloxacin were selected and examined for chromosomal mutations by Sanger sequencing and plasmid-mediated resistance by PCR. Results Of 133 biobanked isolates cultured, 68 (51.1%) and 16 (12%) were identified as Salmonella Typhi and non-typhoidal Salmonella (NTS), respectively. Sequence analysis of gyrA gene revealed the presence of 5 different nonsynonymous mutations, with the most frequent mutation (Ile203Ser) occurring in 12 out of 13 isolates tested. Gyrase B (gyrB) gene had 1 nonsynonymous mutation in 3 out of 13 isolates, substituting phenylalanine with leucine at codon 601 (Phe601Leu). No mutation was observed in parC and parE genes. Two NTS isolates were found to harbour qnrS plasmid-mediated resistant gene of molecular size 550 bp with high ciprofloxacin MIC of 0.5 μg/ml. Conclusion This study reports for the first time in Ghana plasmid-mediated fluoroquinolone resistant gene qnrS in Salmonella clinical isolates. Nonsynonymous mutations of gyrA and gyrB genes likely to confer Salmonella reduced susceptibility to ciprofloxacin were also reported.
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Affiliation(s)
- Godfred Acheampong
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kumasi, Ghana
| | - Michael Owusu
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kumasi, Ghana.,Department of Medical Laboratory Technology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Alex Owusu-Ofori
- Department of Clinical Microbiology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.,Komfo Anokye Teaching Hospital, Kumasi, Ghana
| | - Isaac Osei
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kumasi, Ghana
| | | | - Augustina Sylverken
- Kumasi Centre for Collaborative Research in Tropical Medicine, Kumasi, Ghana.,Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Hung-Jui Kung
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Shu-Ting Cho
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Chih-Horng Kuo
- Institute of Plant and Microbial Biology, Academia Sinica, Taipei, Taiwan
| | - Se Eun Park
- Department of Epidemiology, International Vaccine Institute, Seoul, South Korea.,Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme, 764 Vo Van Kiet, Quant 5, Ho Chi Minh City, Vietnam
| | - Florian Marks
- Department of Epidemiology, International Vaccine Institute, Seoul, South Korea
| | - Yaw Adu-Sarkodie
- Department of Clinical Microbiology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Ellis Owusu-Dabo
- Department of Global and International Health, School of Public Health, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana.
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Kuijpers LMF, Gryseels C, Uk S, Chung P, Bory S, Sreng B, Parry A, Jacobs J, Peeters Grietens K. Enteric Fever in Cambodia: Community Perceptions and Practices Concerning Disease Transmission and Treatment. Am J Trop Med Hyg 2019; 99:1369-1377. [PMID: 30298811 PMCID: PMC6283521 DOI: 10.4269/ajtmh.18-0432] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Enteric fever is a systemic bacterial infection in humans that is endemic in Cambodia and for which antibiotic resistance is increasingly reported. To guide public health programs, this qualitative study sought to explore community perceptions on transmission and treatment. Participant observation was carried out in hospital settings, pharmacies, and at a community level in Phnom Penh. In-depth interviews 39 and one focus group discussion were carried out with blood culture–confirmed enteric fever patients and purposively selected key informants. Informants were theoretically sampled based on initial themes identified using abductive analysis. Nvivo 11 was used for thematic coding. An urgent need to address health literacy concerning the transmission of enteric fever was identified, as lay informants did not link the disease and its symptoms to bacterial contamination of foods and drinks but rather to foods considered “bad” following humoral illness interpretations. As a result, lay informants considered recurrence of enteric fever preventable with appropriate dietary restrictions and Khmer traditional medicines. This study also reveals pluralistic health-care–seeking behavior. For initial and mild symptoms, patients preferred home treatment or traditional healing practices; limited household finances delayed treatment seeking. When symptoms persisted, patients first visited drug outlets or private practitioners, where they received a mix of nonessential medicines and one or more antibiotics often without prescription or confirmation of diagnosis. Inappropriate use of antibiotics was common and was related to diagnostic uncertainty and limited finances, factors which should be addressed during future efforts to improve the uptake of appropriate diagnostics and treatment of enteric fever.
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Affiliation(s)
- Laura Maria Francisca Kuijpers
- Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.,Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium
| | - Charlotte Gryseels
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium
| | - Sambunny Uk
- Independent Researcher, Phnom Penh, Cambodia
| | - Panha Chung
- Sihanouk Hospital Center of HOPE, Phnom Penh, Cambodia
| | | | - Bun Sreng
- Department of Communicable Disease Control, Ministry of Health, Phnom Penh, Cambodia
| | - Amy Parry
- Independent Researcher, Phnom Penh, Cambodia
| | - Jan Jacobs
- Department of Microbiology and Immunology, KU Leuven, Leuven, Belgium.,Department of Clinical Sciences, Institute of Tropical Medicine, Antwerp, Belgium
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Salerno-Goncalves R, Kayastha D, Fasano A, Levine MM, Sztein MB. Crosstalk between leukocytes triggers differential immune responses against Salmonella enterica serovars Typhi and Paratyphi. PLoS Negl Trop Dis 2019; 13:e0007650. [PMID: 31412039 PMCID: PMC6709971 DOI: 10.1371/journal.pntd.0007650] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2019] [Revised: 08/26/2019] [Accepted: 07/23/2019] [Indexed: 12/30/2022] Open
Abstract
Enteric fevers, caused by the Salmonella enterica serovars Typhi (ST), Paratyphi A (PA) and Paratyphi B (PB), are life-threatening illnesses exhibiting very similar clinical symptoms but with distinct epidemiologies, geographical distributions and susceptibilities to antimicrobial treatment. Nevertheless, the mechanisms by which the host recognizes pathogens with high levels of homology, such as these bacterial serovars, remain poorly understood. Using a three-dimensional organotypic model of the human intestinal mucosa and PA, PB, and ST, we observed significant differences in the secretion patterns of pro-inflammatory cytokines and chemokines elicited by these serovars. These cytokines/chemokines were likely to be co-regulated and influenced the function of epithelial cells, such as the production of IL-8. We also found differing levels of polymorphonuclear leukocyte (PMN) migration among various infection conditions that either included or excluded lymphocytes and macrophages (Mϕ), strongly suggesting feedback mechanisms among these cells. Blocking experiments showed that IL-1β, IL-6, IL-8, TNF-α and CCL3 cytokines were involved in the differential regulation of migration patterns. We conclude that the crosstalk among the lymphocytes, Mϕ, PMN and epithelial cells is cytokine/chemokine-dependent and bacterial-serotype specific, and plays a pivotal role in orchestrating the functional efficiency of the innate cells and migratory characteristics of the leukocytes.
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Affiliation(s)
- Rosangela Salerno-Goncalves
- Center for Vaccine Development and Global Health, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Darpan Kayastha
- Center for Vaccine Development and Global Health, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Alessio Fasano
- Mucosal Immunology and Biology Research Center, Massachusetts General Hospital for Children, Boston, MA, United States of America
| | - Myron M. Levine
- Center for Vaccine Development and Global Health, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States of America
| | - Marcelo B. Sztein
- Center for Vaccine Development and Global Health, Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD, United States of America
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30
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Abstract
Purpose of review Enteric fever remains a major global-health concern, estimated to be responsible for between 11.9 and 26.9 million cases annually. Long-term prevention of enteric fever will require improved access to safe drinking water combined with investment in sanitation and hygiene interventions. In the short-to-medium term, new control strategies for typhoid fever have arrived in the form of typhoid Vi-conjugate vaccines (TCVs), offering hope that disease control can be achieved in the near future. Recent findings The diagnosis of enteric fever is complicated by its nonspecific clinical presentation, coupled with the low sensitivity of commonly used diagnostics. Investment in diagnostics has the potential to improve management, to refine estimates of disease burden and to facilitate vaccine impact studies. A new generation of reliable, diagnostic tests is needed that are simultaneously accessible, cost-effective, sensitive, and specific. The emergence and global dissemination of multidrug-resistant, fluoroquinolone-resistant, and extensively drug-resistant (XDR) strains of Salmonella Typhi emphasizes the importance of continued surveillance and appropriate antibiotic stewardship, integrated into a global strategy to address antimicrobial resistance (AMR). Current empirical treatment guidelines are out of date and should be updated to respond to local trends in AMR, so as to guide treatment choices in the absence of robust diagnostics and laboratory facilities. In September 2017, the WHO Strategic Advisory Group of Experts (SAGE) immunization recommended the programmatic use of TCVs in high burden countries. Ongoing and future studies should aim to study the impact of these vaccines in a diverse range of setting and to support the deployment of TCVs in high-burden countries. Summary The advent of new generation TCVs offers us a practical and affordable public-health tool that – for the first time – can be integrated into routine childhood immunization programmes. In this review, we advocate for the deployment of TCVs in line with WHO recommendations, to improve child health and limit the spread of antibiotic-resistant S. Typhi.
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Reed TAN, Krang S, Miliya T, Townell N, Letchford J, Bun S, Sar B, Osbjer K, Seng S, Chou M, By Y, Vanchinsuren L, Nov V, Chau D, Phe T, de Lauzanne A, Ly S, Turner P. Antimicrobial resistance in Cambodia: a review. Int J Infect Dis 2019; 85:98-107. [PMID: 31176035 DOI: 10.1016/j.ijid.2019.05.036] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 05/31/2019] [Accepted: 05/31/2019] [Indexed: 02/01/2023] Open
Abstract
OBJECTIVES Following the launch of the Global Antimicrobial Resistance Surveillance System (GLASS), antimicrobial resistance (AMR) rates in many countries remain poorly described. This review provides an overview of published AMR data from Cambodia in the context of recently initiated national human and food-animal surveillance. METHODS PubMed and the Cochrane Database of Systematic Reviews were searched for articles published from 2000 to 2018, which reported antimicrobial susceptibility testing (AST) data for GLASS specific organisms isolated from Cambodia. Articles were screened using strict inclusion/exclusion criteria. AST data was extracted, with medians and ranges of resistance rates calculated for specific bug-drug combinations. RESULTS Twenty-four papers were included for final analysis, with 20 describing isolates from human populations. Escherichia coli was the most commonly described organism, with median resistance rates from human isolates of 92.8% (n=6 articles), 46.4% (n=4), 55.4% (n=8), and 46.4% (n=5) to ampicillin, 3rd generation cephalosporins, fluoroquinolones, and gentamicin respectively. CONCLUSIONS Whilst resistance rates are high for several GLASS organisms, there were insufficient data to draw robust conclusions about the AMR situation in Cambodia. The recently implemented national AMR surveillance systems will begin to address this data gap.
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Affiliation(s)
- Thomas A N Reed
- Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - Sidonn Krang
- Department of Communicable Diseases Control, Ministry of Health, Phnom Penh, Cambodia
| | - Thyl Miliya
- Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia
| | - Nicola Townell
- Diagnostic Microbiology Development Program, Phnom Penh, Cambodia
| | - Joanne Letchford
- Diagnostic Microbiology Development Program, Phnom Penh, Cambodia
| | - Sreng Bun
- United States Centers for Disease Control and Prevention, Phnom Penh, Cambodia
| | - Borann Sar
- United States Centers for Disease Control and Prevention, Phnom Penh, Cambodia
| | - Kristina Osbjer
- Food and Agriculture Organisation of the United Nations, Phnom Penh, Cambodia
| | - Sokerya Seng
- Food and Agriculture Organisation of the United Nations, Phnom Penh, Cambodia
| | - Monidarin Chou
- Faculty of Pharmacy, University of Health Sciences, Phnom Penh, Cambodia
| | - Youlet By
- Fondation Mérieux, Phnom Penh, Cambodia
| | | | - Vandarith Nov
- National Institute of Public Health, Phnom Penh, Cambodia
| | - Darapheak Chau
- National Institute of Public Health, Phnom Penh, Cambodia
| | - Thong Phe
- Sihanouk Hospital Center of Hope, Phnom Penh, Cambodia
| | | | - Sovann Ly
- Department of Communicable Diseases Control, Ministry of Health, Phnom Penh, Cambodia
| | - Paul Turner
- Cambodia-Oxford Medical Research Unit, Angkor Hospital for Children, Siem Reap, Cambodia; Centre for Tropical Medicine and Global Health, Nuffield Department of Medicine, University of Oxford, Oxford, UK.
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Oo WT, Myat TO, Htike WW, Ussher JE, Murdoch DR, Lwin KT, Oo MZ, Maze MJ, Win HH, Crump JA. Incidence of Typhoid and Paratyphoid Fevers Among Adolescents and Adults in Yangon, Myanmar. Clin Infect Dis 2019; 68:S124-S129. [PMID: 30845332 PMCID: PMC6405279 DOI: 10.1093/cid/ciy1109] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
BACKGROUND Accurate estimates of typhoid disease burden are needed to guide policy decisions, including on vaccine use. Data on the incidence of enteric fever in Myanmar are scarce. We estimated typhoid and paratyphoid fever incidence among adolescents and adults in Yangon, Myanmar, by combining sentinel hospital surveillance with a healthcare utilization survey. METHODS We conducted a population-based household health care utilization survey in the Yangon Region 12 March through 5 April 2018. Multipliers derived from this survey were then applied to hospital-based surveillance of Salmonella Typhi and Paratyphi A bloodstream infections from 5 October 2015 through 4 October 2016 at Yangon General Hospital (YGH) to estimate the incidence of typhoid and paratyphoid fevers among person ≥12 years of age. RESULTS A total of 336 households representing 1598 persons were enrolled in the health care utilization survey, and multipliers were derived based on responses to questions about healthcare seeking in the event of febrile illness. Of 671 Yangon residents enrolled over a 1-year period at YGH, we identified 33 (4.9%) with Salmonella Typhi and 9 (1.3%) with Salmonella Paratyphi A bloodstream infection. After applying multipliers, we estimated that the annual incidence of typhoid was 391 per 100 000 persons and paratyphoid was 107 per 100 000 persons. CONCLUSIONS Enteric fever incidence is high in Yangon, Myanmar, warranting increased attention on prevention and control, including consideration of typhoid conjugate vaccine use as well as nonvaccine control measures. Research on incidence among infants and children, as well as sources and modes of transmission is needed.
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Affiliation(s)
- Win Thandar Oo
- Department of Microbiology, University of Medicine 1, Yangon, Myanmar
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - Tin Ohn Myat
- Department of Microbiology, University of Medicine 1, Yangon, Myanmar
- Centre for International Health, University of Otago, Dunedin, New Zealand
| | - Wah Win Htike
- Department of Microbiology, University of Medicine 1, Yangon, Myanmar
| | - James E Ussher
- Southern Community Laboratories, Dunedin Hospital
- Department of Immunology and Microbiology, University of Otago, Dunedin
| | - David R Murdoch
- Department of Pathology, University of Otago, Christchurch, New Zealand
| | | | - Min Zaw Oo
- Department of Medicine, University of Medicine 1, Yangon, Myanmar
| | - Michael J Maze
- Department of Medicine, University of Otago, Christchurch, New Zealand
| | - Hla Hla Win
- Department of Preventive and Social Medicine
| | - John A Crump
- Centre for International Health, University of Otago, Dunedin, New Zealand
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Ahmedullah H, Khan FY, Al Maslamani M, Al Soub H, Chacko K, Abu Khattab M, Mahmoud S, Howaidy F, Thapur M, Al Madhoun E, Hamed M, Doiphode S, Al Khal A, Deshmukh A. Epidemiological and Clinical Features of Salmonella Typhi Infection Among Adult Patients in Qatar: A Hospital-based Study. Oman Med J 2018; 33:468-472. [PMID: 30410688 DOI: 10.5001/omj.2018.87] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Objectives We sought to describe the epidemiological and clinical features of typhoid fever in Qatar. Methods We conducted a retrospective study of adult patients treated for typhoid fever at Hamad General Hospital and Alkhor Hospital between 2005 and 2012. Results The mean age of the 354 patients enrolled in the study was 28.4±9.3 years; 296 (83.6%) were males. There were 42, 48, 39, 44, 46, 47, 52, and 36 cases of adults with typhoid fever in 2005, 2006, 2007, 2008, 2009, 2010, 2011, and 2012, respectively. Overall, 343 (96.9%) patients had a history of travel to endemic areas. Among them, 93.0% acquired typhoid fever in the Indian subcontinent. Fever was observed in all cases, and the other predominant symptoms were abdominal pain (38.1%), diarrhea (35.6%), and headache (33.1%). Salmonella typhi, showed high resistance to ciprofloxacin (n = 163; 46.0%), and low resistance to ceftriaxone (n = 2; 0.6%). Four patients developed intestinal perforation, which was surgically repaired in two cases. Two patients (0.6%) died. Conclusions Typhoid fever was frequent among immigrants to endemic areas. Travelers returning from endemic areas with suspected typhoid fever should be treated empirically with third-generation cephalosporin after obtaining appropriate cultures. Moreover, preventive measurements such as education on food and water hygiene, and effective vaccination of travelers should be practiced widely among travelers to endemic areas to reduce morbidity and mortality.
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Affiliation(s)
- Hasan Ahmedullah
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | | | - Muna Al Maslamani
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Hussam Al Soub
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Kadavil Chacko
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Mohammed Abu Khattab
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Samar Mahmoud
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Faraj Howaidy
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Maliha Thapur
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Eyad Al Madhoun
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Manal Hamed
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Sanjay Doiphode
- Department of Microbiology, Hamad General Hospital, Doha, Qatar
| | - Abdulatif Al Khal
- Department of Medicine, Infectious Disease Division, Hamad General Hospital, Doha, Qatar
| | - Anand Deshmukh
- Department of Microbiology, Hamad General Hospital, Doha, Qatar
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Cuypers WL, Jacobs J, Wong V, Klemm EJ, Deborggraeve S, Van Puyvelde S. Fluoroquinolone resistance in Salmonella: insights by whole-genome sequencing. Microb Genom 2018; 4. [PMID: 29975627 PMCID: PMC6113872 DOI: 10.1099/mgen.0.000195] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023] Open
Abstract
Fluoroquinolone (FQ)-resistant Salmonella spp. were listed by the WHO in 2017 as priority pathogens for which new antibiotics were urgently needed. The overall global burden of Salmonella infections is high, but differs per region. Whereas typhoid fever is most prevalent in South and South-East Asia, non-typhoidal salmonellosis is prevalent across the globe and associated with a mild gastroenteritis. By contrast, invasive non-typhoidal Salmonella cause bloodstream infections associated with high mortality, particularly in sub-Saharan Africa. Most Salmonella strains from clinical sources are resistant to first-line antibiotics, with FQs now being the antibiotic of choice for treatment of invasive Salmonella infections. However, FQ resistance is increasingly being reported in Salmonella, and multiple molecular mechanisms are already described. Whole-genome sequencing (WGS) is becoming more frequently used to analyse bacterial genomes for antibiotic-resistance markers, and to understand the phylogeny of bacteria in relation to their antibiotic-resistance profiles. This mini-review provides an overview of FQ resistance in Salmonella, guided by WGS studies that demonstrate that WGS is a valuable tool for global surveillance.
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Affiliation(s)
- Wim L Cuypers
- 1Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerpen, Belgium.,2Department of Mathematics and Computer Science, University of Antwerp, Antwerpen, Belgium
| | - Jan Jacobs
- 3Department of Clinical Sciences, Institute of Tropical Medicine, Antwerpen, Belgium.,4Department of Microbiology and Immunology, Katholieke Universiteit Leuven (KU Leuven), Leuven, Belgium
| | - Vanessa Wong
- 5Department of Medicine, University of Cambridge, Addenbrooke's Hospital, Cambridge, UK.,6Wellcome Trust Sanger Institute, Hinxton, UK
| | | | - Stijn Deborggraeve
- 1Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerpen, Belgium
| | - Sandra Van Puyvelde
- 6Wellcome Trust Sanger Institute, Hinxton, UK.,1Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerpen, Belgium
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