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Tanmoy AM, Hooda Y, Sajib MSI, Rahman H, Sarkar A, Das D, Islam N, Kanon N, Rahman MA, Garrett DO, Endtz HP, Luby SP, Shahidullah M, Amin MR, Alam J, Hanif M, Saha SK, Saha S. Trends in antimicrobial resistance amongst Salmonella Typhi in Bangladesh: A 24-year retrospective observational study (1999-2022). PLoS Negl Trop Dis 2024; 18:e0012558. [PMID: 39365840 DOI: 10.1371/journal.pntd.0012558] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Accepted: 09/21/2024] [Indexed: 10/06/2024] Open
Abstract
BACKGROUND Rising antimicrobial resistance (AMR) in Salmonella Typhi restricts typhoid treatment options, heightening concerns for pan-oral drug-resistant outbreaks. However, lack of long-term temporal surveillance data on AMR in countries with high burden like Bangladesh is scarce. Our study explores the AMR trends of Salmonella Typhi isolates from Bangladesh, drawing comparisons with antibiotic consumption to optimize antibiotic stewardship strategies for the country. METHODOLOGY/PRINCIPAL FINDINGS The typhoid fever surveillance from 1999 to 2022 included two pediatric hospitals and three private clinics in Dhaka, Bangladesh. Blood cultures were performed at treating physicians' discretion; cases were confirmed by microbiological serological, and biochemical tests. Antibiotic susceptibility was determined following CLSI guidelines. National antibiotic consumption data for cotrimoxazole, ciprofloxacin, and azithromycin was obtained from IQVIA-MIDAS database for comparison. Over the 24 years of surveillance, we recorded 12,435 culture-confirmed typhoid cases and observed declining resistance to first-line drugs (amoxicillin, chloramphenicol, and cotrimoxazole); multidrug resistance (MDR) decreased from 38% in 1999 to 17% in 2022. Cotrimoxazole consumption dropped from 0.8 to 0.1 Daily defined doses (DDD)/1000/day (1999-2020). Ciprofloxacin non-susceptibility persisted at >90% with unchanged consumption (1.1-1.3 DDD/1000/day, 2002-2020). Low ceftriaxone resistance (<1%) was observed, with slightly rising MIC (0.03 to 0.12 mg/L, 1999-2019). Azithromycin consumption increased (0.1 to 3.8 DDD/1000/day, 1999-2020), but resistance remained ≤4%. CONCLUSION Our study highlights declining MDR amongst Salmonella Typhi in Bangladesh; first-line antimicrobials could be reintroduced as empirical treatment options for typhoid fever if MDR rates further drops below 5%. The analysis also provides baseline data for monitoring the impact of future interventions like typhoid conjugate vaccines on typhoid burden and associated AMR.
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Affiliation(s)
- Arif Mohammad Tanmoy
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, the Netherlands
| | - Yogesh Hooda
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | | | - Anik Sarkar
- Child Health Research Foundation, Dhaka, Bangladesh
| | - Dipu Das
- Child Health Research Foundation, Dhaka, Bangladesh
| | - Nazrul Islam
- Child Health Research Foundation, Dhaka, Bangladesh
| | - Naito Kanon
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | - Denise O Garrett
- Sabin Vaccine Institute, Washington DC, Maryland, United States of America
| | - Hubert P Endtz
- Department of Medical Microbiology and Infectious Diseases, Erasmus MC, Rotterdam, the Netherlands
| | - Stephen P Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Mohammod Shahidullah
- Department of Neonatology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh
| | - Md Ruhul Amin
- Department of Pediatrics, Bangladesh Institute of Child Health, Dhaka, Bangladesh
| | - Jahangir Alam
- Department of Pediatrics, Bangladesh Institute of Child Health, Dhaka, Bangladesh
| | - Mohammed Hanif
- Department of Pediatrics, Bangladesh Institute of Child Health, Dhaka, Bangladesh
| | - Samir K Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Microbiology, Bangladesh Shishu Hospital and Institute, Dhaka, Bangladesh
| | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh
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2
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Agarwal N, Gupta N, Nishant, H S S, Dutta T, Mahajan M. Typhoid Conjugate Vaccine: A Boon for Endemic Regions. Cureus 2024; 16:e56454. [PMID: 38650789 PMCID: PMC11034893 DOI: 10.7759/cureus.56454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/12/2024] [Indexed: 04/25/2024] Open
Abstract
Typhoid fever has the highest disease burden in countries in low- and middle-income countries, primarily located in Asia and Sub-Saharan Africa. Previous typhoid vaccines such as the live attenuated typhoid (Ty21a) vaccine and Vi (virulence) capsular polysaccharide vaccine had the limitation that they could not be administered with other standard childhood immunizations and were ineffective in children under two years of age. To address these shortcomings of the previous vaccines, typhoid conjugate vaccines (TCVs) were developed and prequalified by the World Health Organization. Cross-reacting material and tetanus toxoid are widely used as carrier proteins in TCVs. According to various studies, TCV has higher efficacy, has a more extended protection period, and is safe and immunogenic in infants as young as six months. This review article aims to comprehensively appraise the data available on TCVs' efficacy, duration of protection, safety, and immunogenicity in endemic regions.
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Affiliation(s)
- Nitesh Agarwal
- Department of Pediatrics, Southern Gem Hospital, Hyderabad, IND
| | - Naveen Gupta
- Department of Pediatrics, Happy Family Hospital, Karnal, IND
| | - Nishant
- Department of Pediatrics, Nihan Medical Children Hospital, Patna, IND
| | - Surendra H S
- Department of Pediatrics, Natus Women and Children Hospital, Bengaluru, IND
| | - Trayambak Dutta
- Department of Infectious Disease, Zydus Lifesciences, Ahmedabad, IND
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3
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Hooda Y, Islam S, Kabiraj R, Rahman H, Sarkar H, da Silva KE, Raju RS, Luby SP, Andrews JR, Saha SK, Saha S. Old tools, new applications: Use of environmental bacteriophages for typhoid surveillance and evaluating vaccine impact. PLoS Negl Trop Dis 2024; 18:e0011822. [PMID: 38358956 PMCID: PMC10868810 DOI: 10.1371/journal.pntd.0011822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 11/27/2023] [Indexed: 02/17/2024] Open
Abstract
Typhoid-conjugate vaccines (TCVs) provide an opportunity to reduce the burden of typhoid fever, caused by Salmonella Typhi, in endemic areas. As policymakers design vaccination strategies, accurate and high-resolution data on disease burden is crucial. However, traditional blood culture-based surveillance is resource-extensive, prohibiting its large-scale and sustainable implementation. Salmonella Typhi is a water-borne pathogen, and here, we tested the potential of Typhi-specific bacteriophage surveillance in surface water bodies as a low-cost tool to identify where Salmonella Typhi circulates in the environment. In 2021, water samples were collected and tested for the presence of Salmonella Typhi bacteriophages at two sites in Bangladesh: urban capital city, Dhaka, and a rural district, Mirzapur. Salmonella Typhi-specific bacteriophages were detected in 66 of 211 (31%) environmental samples in Dhaka, in comparison to 3 of 92 (3%) environmental samples from Mirzapur. In the same year, 4,620 blood cultures at the two largest pediatric hospitals of Dhaka yielded 215 (5%) culture-confirmed typhoid cases, and 3,788 blood cultures in the largest hospital of Mirzapur yielded 2 (0.05%) cases. 75% (52/69) of positive phage samples were collected from sewage. All isolated phages were tested against a panel of isolates from different Salmonella Typhi genotypes circulating in Bangladesh and were found to exhibit a diverse killing spectrum, indicating that diverse bacteriophages were isolated. These results suggest an association between the presence of Typhi-specific phages in the environment and the burden of typhoid fever, and the potential of utilizing environmental phage surveillance as a low-cost tool to assist policy decisions on typhoid control.
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Affiliation(s)
- Yogesh Hooda
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | | | | | | | - Kesia E. da Silva
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | | | - Stephen P. Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Samir K. Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Microbiology, Bangladesh Shishu Hospital and Institute, Dhaka, Bangladesh
| | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh
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4
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Saha T, Arisoyin AE, Bollu B, Ashok T, Babu A, Issani A, Jhaveri S, Avanthika C. Enteric Fever: Diagnostic Challenges and the Importance of Early Intervention. Cureus 2023; 15:e41831. [PMID: 37575696 PMCID: PMC10423039 DOI: 10.7759/cureus.41831] [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] [Accepted: 07/12/2023] [Indexed: 08/15/2023] Open
Abstract
Enteric fever is a systemic infection caused by highly virulent Salmonella enterica serovars: Typhi and Paratyphi. Diagnosis of enteric fever is challenging due to a wide variety of clinical features which overlap with other febrile illnesses. The current diagnostic methods are limited because of the suboptimal sensitivity of conventional tests like blood culture in detecting organisms and the invasive nature of bone marrow culture. It emphasizes the need to develop improved and more reliable diagnostic modalities. The rising rates of multidrug-resistant Salmonella strains call for an accurate understanding of the current management of the disease. Proper public health measures and large-scale immunization programs will help reduce the burden of the disease. A comprehensive surveillance system can help detect the chronic carrier state and is crucial in understanding antibiotic susceptibility patterns. We conducted an all-language literature search on Medline, Cochrane, Embase, and Google Scholar till May 2022. The following search words and medical subject headings (MeSH) were used: "enteric fever," "Salmonella Typhi," "multidrug-resistant Salmonella," chronic carrier state," "Salmonella detection, "and "typhoid vaccine." We reviewed the literature on clinical features, pathophysiology, new diagnostic tests, and interventions to prevent the disease. This article explores enteric fever and its various clinical features and addresses the emerging threat of multidrug resistance. It focuses on novel methods for diagnosis and prevention strategies, including vaccines and the use of surveillance systems employed across different parts of the world.
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Affiliation(s)
- Tias Saha
- Internal Medicine, Samorita General Hospital, Faridpur, BGD
- Internal Medicine, Diabetic Association Medical College, Faridpur, BGD
| | | | - Bhaswanth Bollu
- Emergency Medicine, All India Institute of Medical Sciences, New Delhi, IND
| | - Tejaswini Ashok
- Internal Medicine, Jagadguru Sri Shivarathreeshwara Medical College, Mysore, IND
| | - Athira Babu
- Pediatrics, Saudi German Hospital, Dubai, ARE
| | - Ali Issani
- Emergency Medicine, Aga Khan University, Karachi, PAK
| | - Sharan Jhaveri
- Internal Medicine, Nathiba Hargovandas Lakhmichand Municipal Medical College, Ahmedabad, IND
| | - Chaithanya Avanthika
- Pediatrics, Icahn School of Medicine at Mount Sinai, Elmhurst Hospital Center, New York, USA
- Medicine and Surgery, Karnataka Institute of Medical Sciences, Hubli, IND
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5
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Irfan S, Hasan Z, Qamar F, Ghanchi N, Ashraf J, Kanji A, Razzak S, Greig D, Nair S, Hasan R. Ceftriaxone resistant Salmonella enterica serovar Paratyphi A identified in a case of enteric fever: first case report from Pakistan. BMC Infect Dis 2023; 23:267. [PMID: 37101111 PMCID: PMC10132421 DOI: 10.1186/s12879-023-08152-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 03/10/2023] [Indexed: 04/28/2023] Open
Abstract
BACKGROUND Enteric fever is an acute systemic infectious disease associated with substantial morbidity and mortality in low- and middle-income countries (LMIC), with a global burden of 14.3 million cases. Cases of enteric fever or paratyphoid fever, caused by Salmonella enterica serovar Paratyphi A (S. Para A) have been found to rise in many endemic and non-endemic countries. Drug resistance is relatively uncommon in S. Para A. Here we report a case of paratyphoid fever caused by ceftriaxone resistant S. Para A from Pakistan. CASE PRESENTATION A 29-year-old female presented with a history of fever, headache, and shivering. Her blood culture revealed a S. Para A isolate (S7), which was resistant to ceftriaxone, cefixime, ampicillin and ciprofloxacin. She was prescribed oral Azithromycin for 10 days, which resulted in resolution of her symptoms. Two other isolates of S. Para A (S1 and S4), resistant to fluoroquinolone were also selected for comparison. DST and whole genome sequencing was performed for all three isolates. Sequence analysis was performed for identification of drug resistance and phylogeny. Whole Genome Sequencing (WGS) of S7 revealed the presence of plasmids, IncX4 and IncFIB(K). blaCTX-M-15 and qnrS1 genes were found on IncFIB(K). The gyrA S83F mutation conferring fluoroquinolone resistance was also found present. Multi-locus sequence typing (MLST) showed the S7 isolate to belong to ST129. S1 and S4 had the gyrA S83Y and S83F mutations respectively. CONCLUSIONS We highlight the occurrence of plasmid-mediated ceftriaxone resistant strain of S. Para A. This is of significance as ceftriaxone is commonly used to treat paratyphoid fever and resistance in S. Para A is not known. Continuous epidemiological surveillance is required to monitor the transmission and spread of antimicrobial resistance (AMR) among Typhoidal Salmonellae. This will guide treatment options and preventive measures including the need for vaccination against S. Para A in the region.
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Affiliation(s)
- Seema Irfan
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Stadium Road, P.O Box3500, Karachi, 74800, Pakistan.
| | - Zahra Hasan
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Karachi, Pakistan
| | - Farah Qamar
- Department of Pediatrics and Child Health, The Aga Khan University, Karachi, Pakistan
| | - Najia Ghanchi
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Karachi, Pakistan
| | - Javaria Ashraf
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Karachi, Pakistan
| | - Akbar Kanji
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Karachi, Pakistan
| | - Safina Razzak
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Karachi, Pakistan
| | - David Greig
- Gastrointestinal Bacteria Reference Unit, UK Health Security Agency, London, UK
| | - Satheesh Nair
- GASTROINTESTINAL PATHOGENS UNIT Gastrointestinal Bacteria Reference Unit National Infection Service, Public Health England, London, UK
| | - Rumina Hasan
- Department of Pathology and Laboratory Medicine, The Aga Khan University, Karachi, Pakistan
- Faculty of Public Health and Policy, London School of Hygiene and Tropical Medicine, London, UK
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6
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Tanmoy AM, Hooda Y, Sajib MSI, da Silva KE, Iqbal J, Qamar FN, Luby SP, Dougan G, Dyson ZA, Baker S, Garrett DO, Andrews JR, Saha SK, Saha S. Paratype: a genotyping tool for Salmonella Paratyphi A reveals its global genomic diversity. Nat Commun 2022; 13:7912. [PMID: 36564386 PMCID: PMC9782287 DOI: 10.1038/s41467-022-35587-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 12/12/2022] [Indexed: 12/24/2022] Open
Abstract
Salmonella Paratyphi A, the primary etiology of paratyphoid, is estimated to cause 3.4 million infections annually, worldwide. With rising antimicrobial resistance and no licensed vaccines, genomic surveillance is key to track and monitor transmission, but there is currently no reliable genotyping framework for this pathogen. Here, we sequence 817 isolates from South Asia and add 562 publicly available genomes to build a global database representing 37 countries, covering 1917-2019. We develop a single nucleotide polymorphism-based genotyping scheme, Paratype, that segregates Salmonella Paratyphi A population into three primary and nine secondary clades, and 18 genotypes. Each genotype is assigned a unique allele definition located on an essential gene. Using Paratype, we identify spatiotemporal genomic variation and antimicrobial resistance markers. We release Paratype as an open-access tool that can use raw read files from both Illumina and Nanopore platforms, and thus can assist surveillance studies tracking Salmonella Paratyphi A across the globe.
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Affiliation(s)
- 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, UK
| | - Mohammad S I Sajib
- Child Health Research Foundation, Dhaka, Bangladesh
- Institute of Biodiversity, Animal Health and Comparative Medicine, University of Glasgow, Glasgow, UK
| | - Kesia E da Silva
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Junaid Iqbal
- Department of Paediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Farah N Qamar
- Department of Paediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Stephen P Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Gordon Dougan
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
| | - Zoe A Dyson
- Wellcome Trust Sanger Institute, Hinxton, Cambridge, CB10 1SA, UK
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Department of Medicine, University of Cambridge, Cambridge, UK
- Department of Infection Biology, London School of Hygiene and Tropical Medicine, London, UK
- Department of Infectious Diseases, Central Clinical School, Monash University, Melbourne, VIC, 3004, Australia
| | - Stephen Baker
- Cambridge Institute of Therapeutic Immunology and Infectious Disease, Department of Medicine, University of Cambridge, Cambridge, UK
| | - Denise O Garrett
- Applied Epidemiology Team, Sabin Vaccine Institute, Washington, DC, USA
| | - Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Samir K Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Department of Microbiology, Bangladesh Shishu Hospital and Institute, Dhaka, Bangladesh
| | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh.
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7
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Saha SK, Tabassum N, Saha S. Typhoid Conjugate Vaccine - an urgent tool to combat typhoid, and tackle antimicrobial resistance. J Infect Dis 2021; 224:S788-S791. [PMID: 34528685 PMCID: PMC8687048 DOI: 10.1093/infdis/jiab443] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Typhoid is endemic in many countries in South Asia and sub-Saharan Africa. The high burden of this age-old, preventable disease exacerbates constraints on the health systems of these countries. Currently, most patients are treated effectively in the community or outpatient departments, however, with rising antimicrobial resistance and the dearth of novel antimicrobials in the horizon, we risk losing our primary defense against typhoid. Extensively drug-resistant Salmonella Typhi is spreading, and azithromycin is the last oral drug to continue treating typhoid in the community. With increasing azithromycin resistance, emergence of pan-oral drug resistant Salmonella Typhi is imminent. The high burden of typhoid is also an underlying cause of the unnecessary use of antimicrobials. In addition to implementing water sanitation and hygiene interventions to prevent typhoid, it is imperative to rapidly roll out typhoid conjugate vaccines in endemic countries. This will not only reduce the burden of typhoid, but also aid in interrupting the trend of increasing antimicrobial resistance.
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Affiliation(s)
- Samir K Saha
- Child Health Research Foundation, Dhaka 1207, Bangladesh.,Department of Microbiology, Dhaka Shishu Hospital, Bangladesh Institute of Child Health, Dhaka 1207, Bangladesh
| | | | - Senjuti Saha
- Child Health Research Foundation, Dhaka 1207, Bangladesh
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8
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Hasanuzzaman M, Saha S, Malaker R, Rahman H, Sajib MSI, Das RC, Islam M, Hamer DH, Darmstadt GL, Saha SK. Comparison of Culture, Antigen Test, and Polymerase Chain Reaction for Pneumococcal Detection in Cerebrospinal Fluid of Children. J Infect Dis 2021; 224:S209-S217. [PMID: 34469562 PMCID: PMC8409532 DOI: 10.1093/infdis/jiab073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Background Sensitivity of culture for the detection of Streptococcus pneumoniae is limited by prior antibiotic exposure. Immunochromatographic test (ICT) is highly sensitive and specific for pneumococcal antigen detection in the cerebrospinal fluid (CSF) of meningitis cases. We determined the specificity and sensitivity of culture, ICT, and polymerase chain reaction (PCR) and the effect of antibiotic exposure on their performance. Methods CSF specimens from suspected meningitis cases admitted to Dhaka Shishu Hospital, Bangladesh, were tested using culture, ICT and PCR. Additionally, 165 specimens collected from 69 pneumococcal cases after antibiotic treatment were tested. Results Of 1883 specimens tested, culture detected 9, quantitative PCR (qPCR) detected 184, and ICT detected 207 pneumococcal cases (including all culture and qPCR positives). In comparison to ICT, sensitivity of culture was 4.4% and of qPCR was 90.6%; both were 100% specific. After antibiotic exposure, culture sensitivity plummeted rapidly; conventional PCR and qPCR sensitivity disappeared after day 6 and 20, respectively. ICT detected pneumococcal antigen for >10 weeks. Conclusions While culture provides the most information about bacterial characteristics, in high antibiotic exposure settings, ICT exhibits maximum sensitivity. We recommend culture and ICT as mainstay for pneumococcal diagnosis and surveillance; qPCR can generate additional molecular data where possible.
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Affiliation(s)
- Md Hasanuzzaman
- Child Health Research Foundation, Dhaka, Bangladesh.,Microbiology Program, Department of Mathematics and Natural Sciences, Brac University, Dhaka, Bangladesh
| | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh
| | - Roly Malaker
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | | | - Rajib C Das
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | - Davidson H Hamer
- Department of Global Health, Boston University School of Public Health, Boston, Massachusetts, USA.,Section of Infectious Disease, Department of Medicine, Boston University School of Medicine, Boston, Massachusetts, USA.,National Emerging Infectious Disease Laboratory, Boston University, Boston, Massachusetts, USA
| | - Gary L Darmstadt
- Department of Pediatrics, Stanford University School of Medicine, Stanford, California, USA
| | - Samir K Saha
- Child Health Research Foundation, Dhaka, Bangladesh.,Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh.,Bangladesh Institute of Child Health, Dhaka, Bangladesh
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9
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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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10
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Saha S, Sayeed KMI, Saha S, Islam MS, Rahaman A, Islam M, Rahman H, Das R, Hasan MM, Uddin MJ, Tanmoy AM, Ahmed ASMNU, Luby SP, Andrews JR, Garrett DO, Saha SK. Hospitalization of Pediatric Enteric Fever Cases, Dhaka, Bangladesh, 2017-2019: Incidence and Risk Factors. Clin Infect Dis 2020; 71:S196-S204. [PMID: 33258942 PMCID: PMC7705877 DOI: 10.1093/cid/ciaa1356] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Enteric fever causes substantial morbidity and mortality in low- and middle-income countries. Here, we analyzed Surveillance for Enteric Fever in Asia Project (SEAP) data to estimate the burden of enteric fever hospitalization among children aged <15 years and identify risk factors for hospitalization in Bangladesh. METHODS SEAP used hospital surveillance paired with a community-based health-care utilization assessment. In SEAP hospital surveillance, blood was obtained for culture from children aged <15 years with ≥3 days of fever. In the hospital catchment area, a health-care utilization survey (HCUS) was conducted to estimate the proportion of febrile children hospitalized at the study hospitals. We analyzed hospital surveillance and HCUS data to estimate the health care-adjusted incidence of enteric fever hospitalization, and conducted univariable and multivariable logistic regressions. RESULTS From July 2017 through June 2019, 2243 laboratory-confirmed enteric fever cases were detected in 2 study hospitals; 673 (30%) were hospitalized. The health care-adjusted incidence of enteric fever hospitalization among children <15 years old was 303/100 000 children/year (95% confidence interval [CI], 293-313). Salmonella Typhi contributed most to the enteric fever hospitalization incidence (277/100 000 children/year; 95% CI, 267-287). The incidence was highest among children aged 2 to <5 years (552/100 000 children/year; 95% CI, 522-583), followed by those aged <2 years (316/100 000 children/year; 95% CI, 288-344). Factors independently associated with enteric fever hospitalization included fever duration, diarrhea, vomiting, abdominal pain, and leukocytopenia. CONCLUSIONS We estimated a high burden of hospitalization due to enteric fever among children aged <5 years in Bangladesh. The introduction of a typhoid conjugate vaccine would protect children from typhoid and avert typhoid hospitalizations.
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Affiliation(s)
- Shampa Saha
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | - Senjuti Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | | | | | | | - Raktim Das
- Child Health Research Foundation, Dhaka, Bangladesh
| | | | | | | | - A S M Nawshad Uddin Ahmed
- Child Health Research Foundation, Dhaka, Bangladesh
- Bangladesh Institute of Child Health, Dhaka Shishu Hospital, Sher-E-Bangla Nagar, Dhaka, Bangladesh
| | - Stephen P Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Jason R Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, USA
| | - Denise O Garrett
- Applied Epidemiology, Sabin Vaccine Institute, Washington, DC, USA
| | - Samir K Saha
- Child Health Research Foundation, Dhaka, Bangladesh
- Bangladesh Institute of Child Health, Dhaka Shishu Hospital, Sher-E-Bangla Nagar, Dhaka, Bangladesh
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11
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Longley AT, Hemlock C, Date K, Luby SP, Andrews JR, Saha SK, Bogoch II, Yousafzai MT, Garrett DO, Qamar FN. Illness Severity and Outcomes Among Enteric Fever Cases From Bangladesh, Nepal, and Pakistan: Data From the Surveillance for Enteric Fever in Asia Project, 2016-2019. Clin Infect Dis 2020; 71:S222-S231. [PMID: 33258929 PMCID: PMC7705875 DOI: 10.1093/cid/ciaa1320] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
BACKGROUND Enteric fever can lead to prolonged hospital stays, clinical complications, and death. The Surveillance for Enteric Fever in Asia Project (SEAP), a prospective surveillance study, characterized the burden of enteric fever, including illness severity, in selected settings in Bangladesh, Nepal, and Pakistan. We assessed disease severity, including hospitalization, clinical complications, and death among SEAP participants. METHODS We analyzed clinical and laboratory data from blood culture-confirmed enteric fever cases enrolled in SEAP hospitals and associated network laboratories from September 2016 to September 2019. We used hospitalization and duration of hospital stay as proxies for severity. We conducted a follow-up interview 6 weeks after enrollment to ascertain final outcomes. RESULTS Of the 8705 blood culture-confirmed enteric fever cases enrolled, we identified 6 deaths (case-fatality ratio, .07%; 95% CI, .01-.13%), 2 from Nepal, 4 from Pakistan, and none from Bangladesh. Overall, 1.7% (90/5205) of patients recruited from SEAP hospitals experienced a clinical complication (Bangladesh, 0.6% [18/3032]; Nepal, 2.3% [12/531]; Pakistan, 3.7% [60/1642]). The most identified complications were hepatitis (n = 36), septic shock (n = 22), and pulmonary complications/pneumonia (n = 13). Across countries, 32% (2804/8669) of patients with hospitalization data available were hospitalized (Bangladesh, 27% [1295/4868]; Nepal, 29% [455/1595]; Pakistan, 48% [1054/2206]), with a median hospital stay of 5 days (IQR, 3-7). CONCLUSIONS While defined clinical complications and deaths were uncommon at the SEAP sites, the high proportion of hospitalizations and prolonged hospital stays highlight illness severity and the need for enteric fever control measures, including the use of typhoid conjugate vaccines.
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Affiliation(s)
- Ashley T Longley
- National Foundation for the Centers for Disease Control and Prevention, Atlanta, Georgia, USA
- Global Immunization Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Caitlin Hemlock
- Applied Epidemiology, Sabin Vaccine Institute, Washington, DC, USA
| | - Kashmira Date
- Global Immunization Division, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - Stephen P Luby
- Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA
| | - Jason R Andrews
- Infectious Diseases and Geographic Medicine, Stanford University, Stanford, California, USA
| | - Samir K Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
- Bangladesh Institute of Child Health, Dhaka Shishu Hospital, Sher-E-Bangla Nagar, Dhaka, Bangladesh
| | - Isaac I Bogoch
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
| | - Mohammad T Yousafzai
- Department of Pediatrics and Child Health, Aga Khan University, Karachi, Pakistan
| | - Denise O Garrett
- Applied Epidemiology, Sabin Vaccine Institute, Washington, DC, USA
| | - Farah N Qamar
- Department of Medicine, University of Toronto, Toronto, Ontario, Canada
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12
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Saha S, Sajib MSI, Garrett D, Qamar FN. Antimicrobial Resistance in Typhoidal Salmonella: Around the World in 3 Days. Clin Infect Dis 2020; 71:S91-S95. [PMID: 32725234 PMCID: PMC7388716 DOI: 10.1093/cid/ciaa366] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
With the increasing antibacterial resistance in typhoidal Salmonella and the dearth of novel antimicrobials on the horizon, we risk losing our primary defense against widespread morbidity and mortality from enteric fever. During 26-28 March 2019, researchers from around the world came together in Hanoi, Vietnam, and shared some of their latest findings on antimicrobial resistance. From the 258 abstracts presented at the conference, at least 50 discussed phenotypic and genotypic characteristics of antimicrobial resistance in typhoidal Salmonella, covering data of at least 24 different countries, spanning 5 continents. Here, we summarize the key findings, focusing on our global journey ahead.
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Affiliation(s)
- Senjuti Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka, Bangladesh
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, USA
| | | | | | - Farah N Qamar
- Department of Pediatrics and Child Health, Karachi, Pakistan
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13
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Saha S, Islam MS, Sajib MSI, Saha S, Uddin MJ, Hooda Y, Hasan M, Amin MR, Hanif M, Shahidullah M, Islam M, Luby SP, Andrews JR, Saha SK. Epidemiology of Typhoid and Paratyphoid: Implications for Vaccine Policy. Clin Infect Dis 2020; 68:S117-S123. [PMID: 30845325 PMCID: PMC6405278 DOI: 10.1093/cid/ciy1124] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background Typhoid and paratyphoid remain the most common bloodstream infections in many resource-poor settings. The World Health Organization recommends typhoid conjugate vaccines for country-specific introduction, but questions regarding typhoid and paratyphoid epidemiology persist, especially regarding their severity in young children. Methods We conducted enteric fever surveillance in Bangladesh from 2004 through 2016 in the inpatient departments of 2 pediatric hospitals and the outpatient departments of 1 pediatric hospital and 1 private consultation clinic. Blood cultures were conducted at the discretion of the treating physicians; cases of culture-confirmed typhoid/paratyphoid were included. Hospitalizations and durations of hospitalizations were used as proxies for severity in children <12 years old. Results We identified 7072 typhoid and 1810 paratyphoid culture-confirmed cases. There was no increasing trend in the proportion of paratyphoid over the 13 years. The median age in the typhoid cases was 60 months, and 15% of the cases occurred in children <24 months old. The median age of the paratyphoid cases was significantly higher, at 90 months (P < .001); 9.4% were in children <24 months old. The proportion of children (<12 years old) hospitalized with typhoid and paratyphoid (32% and 21%, respectively) decreased with age; there was no significant difference in durations of hospitalizations between age groups. However, children with typhoid were hospitalized for longer than those with paratyphoid. Conclusions Typhoid and paratyphoid fever are common in Dhaka, including among children under 2 years old, who have equivalent disease severity as older children. Early immunization with typhoid conjugate vaccines could avert substantial morbidity, but broader efforts are required to reduce the paratyphoid burden.
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Affiliation(s)
- Senjuti Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh.,Department of Infectious Diseases, Stanford University School of Medicine, California
| | - Md Shfiqul Islam
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | | | - Shampa Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Mohammad Jamal Uddin
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Yogesh Hooda
- Department of Biochemistry, University of Toronto, Ontario, Canada
| | - Md Hasan
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Md Ruhul Amin
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh.,Bangladesh Institute of Child Health, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh
| | - Mohammed Hanif
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh.,Bangladesh Institute of Child Health, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh.,Popular Diagnostic Center, Dhaka, Bangladesh
| | - Mohammad Shahidullah
- Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh.,Shishu Shasthya Foundation Hospital, Dhaka, Bangladesh
| | - Maksuda Islam
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Stephen P Luby
- Department of Infectious Diseases, Stanford University School of Medicine, California
| | - Jason R Andrews
- Department of Infectious Diseases, Stanford University School of Medicine, California
| | - Samir K Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh.,Bangladesh Institute of Child Health, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh.,Popular Diagnostic Center, Dhaka, Bangladesh
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14
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Hooda Y, Sajib MSI, Rahman H, Luby SP, Bondy-Denomy J, Santosham M, Andrews JR, Saha SK, Saha S. Molecular mechanism of azithromycin resistance among typhoidal Salmonella strains in Bangladesh identified through passive pediatric surveillance. PLoS Negl Trop Dis 2019; 13:e0007868. [PMID: 31730615 PMCID: PMC6881056 DOI: 10.1371/journal.pntd.0007868] [Citation(s) in RCA: 85] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 11/27/2019] [Accepted: 10/24/2019] [Indexed: 12/11/2022] Open
Abstract
Background With the rise in fluoroquinolone-resistant Salmonella Typhi and the recent emergence of ceftriaxone resistance, azithromycin is one of the last oral drugs available against typhoid for which resistance is uncommon. Its increasing use, specifically in light of the ongoing outbreak of extensively drug-resistant (XDR) Salmonella Typhi (resistant to chloramphenicol, ampicillin, cotrimoxazole, streptomycin, fluoroquinolones and third-generation cephalosporins) in Pakistan, places selective pressure for the emergence and spread of azithromycin-resistant isolates. However, little is known about azithromycin resistance in Salmonella, and no molecular data are available on its mechanism. Methods and findings We conducted typhoid surveillance in the two largest pediatric hospitals of Bangladesh from 2009–2016. All typhoidal Salmonella strains were screened for azithromycin resistance using disc diffusion and resistance was confirmed using E-tests. In total, we identified 1,082 Salmonella Typhi and Paratyphi A strains; among these, 13 strains (12 Typhi, 1 Paratyphi A) were azithromycin-resistant (MIC range: 32–64 μg/ml) with the first case observed in 2013. We sequenced the resistant strains, but no molecular basis of macrolide resistance was identified by the currently available antimicrobial resistance prediction tools. A whole genome SNP tree, made using RAxML, showed that the 12 Typhi resistant strains clustered together within the 4.3.1.1 sub-clade (H58 lineage 1). We found a non-synonymous single-point mutation exclusively in these 12 strains in the gene encoding AcrB, an efflux pump that removes small molecules from bacterial cells. The mutation changed the conserved amino acid arginine (R) at position 717 to a glutamine (Q). To test the role of R717Q present in azithromycin-resistant strains, we cloned acrB from azithromycin-resistant and sensitive strains, expressed them in E. coli, Typhi and Paratyphi A strains and tested their azithromycin susceptibility. Expression of AcrB-R717Q in E. coli and Typhi strains increased the minimum inhibitory concentration (MIC) for azithromycin by 11- and 3-fold respectively. The azithromycin-resistant Paratyphi A strain also contained a mutation at R717 (R717L), whose introduction in E. coli and Paratyphi A strains increased MIC by 7- and 3-fold respectively, confirming the role of R717 mutations in conferring azithromycin resistance. Conclusions This report confirms 12 azithromycin-resistant Salmonella Typhi strains and one Paratyphi A strain. The molecular basis of this resistance is one mutation in the AcrB protein at position 717. This is the first report demonstrating the impact of this non-synonymous mutation in conferring macrolide resistance in a clinical setting. With increasing azithromycin use, strains with R717 mutations may spread and be acquired by XDR strains. An azithromycin-resistant XDR strain would shift enteric fever treatment from outpatient departments, where patients are currently treated with oral azithromycin, to inpatient departments to be treated with injectable antibiotics like carbapenems, thereby further burdening already struggling health systems in endemic regions. Moreover, with the dearth of novel antimicrobials in the horizon, we risk losing our primary defense against widespread mortality from typhoid. In addition to rolling out the WHO prequalified typhoid conjugate vaccine in endemic areas to decrease the risk of pan-resistant Salmonella Typhi strains, it is also imperative to implement antimicrobial stewardship and water sanitation and hygiene intervention to decrease the overall burden of enteric fever. With the outbreak of extensively resistant (XDR) typhoid fever in Pakistan, azithromycin has become the last oral drug to treat typhoid. Although no azithromycin resistant XDR isolate has been reported to date, the increasing use of azithromycin and the clear historical record of widespread dissemination of resistance to all previously widely used antimicrobials by typhoidal Salmonella, suggest we will soon face strains resistant to all oral antibiotics. This makes it imperative to elucidate the mechanism of azithromycin resistance in typhoidal Salmonella. We tested 1,082 typhoidal Salmonella isolates from the two largest pediatric hospitals of Bangladesh and identified 13 azithromycin-resistant isolates. Using comparative genomics, we identified a mutation in a specific protein called AcrB that makes these isolates resistant to azithromycin. All azithromycin-resistant strains were susceptible to cephalosporin but resistant to all other oral antibiotics. The Pakistan outbreak strain is resistant to all common oral antibiotics and only susceptible to azithromycin. Acquisition of the plasmid that confers cephalosporin resistance in XDR strains by the Bangladeshi azithromycin-resistant strains or rise of the AcrB mutation in the XDR strains could be the end of oral treatment for typhoid. This poses serious threats to the health system of LMICs where typhoid is endemic. Currently, the majority of typhoid patients are prescribed oral treatment in the outpatient department, but an azithromycin-resistant XDR strain would shift enteric fever treatment from outpatient departments to inpatient departments to be treated with injectable antibiotics like carbapenems, further burdening already struggling health systems in endemic regions. Moreover, with the dearth of novel antimicrobials in the horizon, we risk losing our primary defense against widespread mortality from enteric fever.
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Affiliation(s)
- Yogesh Hooda
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
- MRC Laboratory of Molecular Biology, Cambridge, United Kingdom
| | - Mohammad S. I. Sajib
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Hafizur Rahman
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
| | - Stephen P. Luby
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Joseph Bondy-Denomy
- Department of Microbiology and Immunology, University of California, San Francisco, San Francisco, California, United States of America
- Quantitative Biosciences Institute, University of California, San Francisco, San Francisco, California, United States of America
| | - Mathuram Santosham
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
| | - Jason R. Andrews
- Division of Infectious Diseases and Geographic Medicine, Stanford University School of Medicine, Stanford, California, United States of America
| | - Samir K. Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
- Bangladesh Institute of Child Health, Dhaka Shishu Hospital, Dhaka, Bangladesh
- * E-mail: (SKS); (SS)
| | - Senjuti Saha
- Child Health Research Foundation, Department of Microbiology, Dhaka Shishu Hospital, Dhaka, Bangladesh
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland, United States of America
- * E-mail: (SKS); (SS)
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15
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Bentsi-Enchill AD, Pollard AJ. A Turning Point in Typhoid Control. J Infect Dis 2019; 218:S185-S187. [PMID: 30189009 PMCID: PMC6226784 DOI: 10.1093/infdis/jiy417] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/29/2018] [Indexed: 12/03/2022] Open
Affiliation(s)
- Adwoa D Bentsi-Enchill
- Department of Immunization, Vaccines and Biologicals, World Health Organization, Geneva, Switzerland
| | - Andrew J Pollard
- Oxford Vaccine Group, Department of Paediatrics, University of Oxford, United Kingdom.,National Institute for Health Research Oxford Biomedical Research Centre, United Kingdom
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