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Yin X, Li Y, Rönn MM, Li S, Yuan Y, Gift TL, Hsu K, Salomon JA, Grad YH, Yaesoubi R. Assessing thresholds of resistance prevalence at which empiric treatment of gonorrhea should change among men who have sex with men in the US: A cost-effectiveness analysis. PLoS Med 2024; 21:e1004424. [PMID: 38976754 DOI: 10.1371/journal.pmed.1004424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Accepted: 06/05/2024] [Indexed: 07/10/2024] Open
Abstract
BACKGROUND Since common diagnostic tests for gonorrhea do not provide information about susceptibility to antibiotics, treatment of gonorrhea remains empiric. Antibiotics used for empiric therapy are usually changed once resistance prevalence exceeds a certain threshold (e.g., 5%). A low switch threshold is intended to increase the probability that an infection is successfully treated with the first-line antibiotic, but it could also increase the pace at which recommendations are switched to newer antibiotics. Little is known about the impact of changing the switch threshold on the incidence of gonorrhea, the rate of treatment failure, and the overall cost and quality-adjusted life-years (QALYs) associated with gonorrhea. METHODS AND FINDINGS We developed a transmission model of gonococcal infection with multiple resistant strains to project gonorrhea-associated costs and loss in QALYs under different switch thresholds among men who have sex with men (MSM) in the United States. We accounted for the costs and disutilities associated with symptoms, diagnosis, treatment, and sequelae, and combined costs and QALYs in a measure of net health benefit (NHB). Our results suggest that under a scenario where 3 antibiotics are available over the next 50 years (2 suitable for the first-line therapy of gonorrhea and 1 suitable only for the retreatment of resistant infections), changing the switch threshold between 1% and 10% does not meaningfully impact the annual number of gonorrhea cases, total costs, or total QALY losses associated with gonorrhea. However, if a new antibiotic is to become available in the future, choosing a lower switch threshold could improve the population NHB. If in addition, drug-susceptibility testing (DST) is available to inform retreatment regimens after unsuccessful first-line therapy, setting the switch threshold at 1% to 2% is expected to maximize the population NHB. A limitation of our study is that our analysis only focuses on the MSM population and does not consider the influence of interventions such as vaccine and common use of rapid drugs susceptibility tests to inform first-line therapy. CONCLUSIONS Changing the switch threshold for first-line antibiotics may not substantially change the health and financial outcomes associated with gonorrhea. However, the switch threshold could be reduced when newer antibiotics are expected to become available soon or when in addition to future novel antibiotics, DST is also available to inform retreatment regimens.
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Affiliation(s)
- Xuecheng Yin
- Department of Management Science and Information Systems, Spears School of Business, Oklahoma State University, Tulsa, Oklahoma, United States of America
- Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut, United States of America
- Yale Public Health Modeling Unit, Yale School of Public Health, New Haven, Connecticut, United States of America
| | - Yunfei Li
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Minttu M Rönn
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Song Li
- College of Computer Science and Technology/School of Cyber Science and Technology, Zhejiang University, Hangzhou, China
| | - Yue Yuan
- Altfest Personal Wealth Management, New York, New York, United States of America
| | - Thomas L Gift
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Katherine Hsu
- Massachusetts Department of Public Health, Boston, Massachusetts, United States of America
| | - Joshua A Salomon
- Department of Health Policy, Stanford University School of Medicine, Stanford, California, United States of America
| | - Yonatan H Grad
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, United States of America
| | - Reza Yaesoubi
- Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut, United States of America
- Yale Public Health Modeling Unit, Yale School of Public Health, New Haven, Connecticut, United States of America
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Yaesoubi R, Xi Q, Hsu K, Gift TL, St. Cyr SB, Rönn MM, Salomon JA, Grad YH. The Impact of Rapid Drug Susceptibility Tests on Gonorrhea Burden and the Life Span of Antibiotic Treatments: A Modeling Study Among Men Who Have Sex With Men in the United States. Am J Epidemiol 2024; 193:17-25. [PMID: 37625444 PMCID: PMC10773484 DOI: 10.1093/aje/kwad175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 05/23/2023] [Accepted: 08/22/2023] [Indexed: 08/27/2023] Open
Abstract
Rapid point-of-care tests that diagnose gonococcal infections and identify susceptibility to antibiotics enable individualized treatment. This could improve patient outcomes and slow the emergence and spread of antibiotic resistance. However, little is known about the long-term impact of such diagnostics on the burden of gonorrhea and the effective life span of antibiotics. We used a mathematical model of gonorrhea transmission among men who have sex with men in the United States to project the annual rate of reported gonorrhea cases and the effective life span of ceftriaxone, the recommended antibiotic for first-line treatment of gonorrhea, as well as 2 previously recommended antibiotics, ciprofloxacin and tetracycline, when a rapid drug susceptibility test that estimates susceptibility to ciprofloxacin and tetracycline is available. The use of a rapid drug susceptibility test with ≥50% sensitivity and ≥95% specificity, defined in terms of correct ascertainment of drug susceptibility and nonsusceptibility status, could increase the combined effective life span of ciprofloxacin, tetracycline, and ceftriaxone by at least 2 years over 25 years of simulation. If test specificity is imperfect, however, the increase in the effective life span of antibiotics is accompanied by an increase in the rate of reported gonorrhea cases even under perfect sensitivity.
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Affiliation(s)
- Reza Yaesoubi
- Correspondence to Reza Yaesoubi, Department of Health Policy and Management, Yale School of Public Health, 350 George Street, Room 308, New Haven, CT 06510 (e-mail: )
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Reichert E, Yaesoubi R, Rönn MM, Gift TL, Salomon JA, Grad YH. Resistance-minimising strategies for introducing a novel antibiotic for gonorrhoea treatment: a mathematical modelling study. THE LANCET. MICROBE 2023; 4:e781-e789. [PMID: 37619582 PMCID: PMC10865326 DOI: 10.1016/s2666-5247(23)00145-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 03/17/2023] [Accepted: 05/03/2023] [Indexed: 08/26/2023]
Abstract
BACKGROUND Gonorrhoea is a highly prevalent sexually transmitted infection and an urgent public health concern because of increasing antibiotic resistance in Neisseria gonorrhoeae. Only ceftriaxone remains as the recommended treatment in the USA. With the prospect of new anti-gonococcal antibiotics being approved, we aimed to evaluate how to deploy a new drug to maximise its clinically useful lifespan. METHODS We used a compartmental model of gonorrhoea transmission in a US population of men who have sex with men (MSM) to compare strategies for introducing a new antibiotic for gonorrhoea treatment. The MSM population was stratified into three sexual activity groups (low, intermediate, and high) characterised by annual rates of partner change. The four introduction strategies tested were: (1) random 50-50 allocation, where each treatment-seeking infected individual had a 50% probability of receiving either drug A (current drug; a ceftriaxone-like antibiotic) or drug B (a new antibiotic), effective at time 0; (2) combination therapy of both the current drug and the new antibiotic; (3) reserve strategy, by which the new antibiotic was held in reserve until the current therapy reached a 5% threshold prevalence of resistance; and (4) gradual switch, or the gradual introduction of the new drug until random 50-50 allocation was reached. The primary outcome of interest was the time until 5% prevalence of resistance to each of the drugs (the new drug and the current ceftriaxone-like antibiotic); sensitivity of the primary outcome to the properties of the new antibiotic, specifically the probability of resistance emergence after treatment and the fitness costs of resistance, was explored. Secondary outcomes included the time to a 1% resistance threshold for each drug, as well as population-level prevalence, mean and range annual incidence, and the cumulative number of incident gonococcal infections. FINDINGS Under baseline model conditions, a 5% prevalence of resistance to each of drugs A and B was reached within 13·9 years with the reserve strategy, 18·2 years with the gradual switch strategy, 19·2 years with the random 50-50 allocation strategy, and 19·9 years with the combination therapy strategy. The reserve strategy was consistently inferior for mitigating antibiotic resistance under the parameter space explored and was increasingly outperformed by the other strategies as the probability of de novo resistance emergence decreased and as the fitness costs associated with resistance increased. Combination therapy tended to prolong the development of antibiotic resistance and minimise the number of annual gonococcal infections (under baseline model conditions, mean number of incident infections per year 178 641 [range 177 998-181 731] with combination therapy, 180 084 [178 011-184 405] with the reserve strategy). INTERPRETATION Our study argues for rapid introduction of new anti-gonococcal antibiotics, recognising that the feasibility of each strategy must incorporate cost, safety, and other practical concerns. The analyses should be revisited once robust estimates of key parameters-ie, the likelihood of emergence of resistance and fitness costs of resistance for the new antibiotic-are available. FUNDING US Centers for Disease Control and Prevention, National Institute of Allergy and Infectious Diseases.
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Affiliation(s)
- Emily Reichert
- Department of Immunology and Infectious Diseases, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Reza Yaesoubi
- Department of Health Policy and Management, Yale School of Public Health, New Haven, CT, USA
| | - Minttu M Rönn
- Department of Global Health and Population, Harvard TH Chan School of Public Health, Boston, MA, USA
| | - Thomas L Gift
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Joshua A Salomon
- Department of Health Policy, Stanford University School of Medicine, Stanford, CA, USA
| | - Yonatan H Grad
- Department of Immunology and Infectious Diseases, Harvard TH Chan School of Public Health, Boston, MA, USA.
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Reichert E, Yaesoubi R, Rönn MM, Gift TL, Salomon JA, Grad YH. Resistance-minimizing strategies for introducing a novel antibiotic for gonorrhea treatment: a mathematical modeling study. MEDRXIV : THE PREPRINT SERVER FOR HEALTH SCIENCES 2023:2023.02.14.23285710. [PMID: 36824857 PMCID: PMC9949214 DOI: 10.1101/2023.02.14.23285710] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Background Gonorrhea is a highly prevalent sexually transmitted infection and an urgent public health concern due to increasing antibiotic resistance. Only ceftriaxone remains as the recommended treatment in the U.S. The prospect of approval of new anti-gonococcal antibiotics raises the question of how to deploy a new drug to maximize its clinically useful lifespan. Methods We used a compartmental model of gonorrhea transmission in the U.S. population of men who have sex with men to compare strategies for introducing a new antibiotic for gonorrhea treatment. The strategies tested included holding the new antibiotic in reserve until the current therapy reached a threshold prevalence of resistance; using either drug, considering immediate and gradual introduction of the new drug; and combination therapy. The primary outcome of interest was the time until 5% prevalence of resistance to both the novel drug and to the current first-line drug (ceftriaxone). Findings The reserve strategy was consistently inferior for mitigating antibiotic resistance under the parameter space explored. The reserve strategy was increasingly outperformed by the other strategies as the probability of de novo resistance emergence decreased and as the fitness costs associated with resistance increased. Combination therapy tended to prolong the development of antibiotic resistance and minimize the number of annual gonococcal infections. Interpretation Our study argues for rapid introduction of new anti-gonococcal antibiotics, recognizing that the feasibility of each strategy must incorporate cost, safety, and other practical concerns. The analyses should be revisited once robust estimates of key parameters-likelihood of emergence of resistance and fitness costs of resistance for the new antibiotic-are available. Funding U.S. Centers for Disease Control and Prevention (CDC), National Institute of Allergy and Infectious Diseases.
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Affiliation(s)
- E Reichert
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
| | - R Yaesoubi
- Department of Health Policy and Management, Yale School of Public Health, New Haven, Connecticut, USA
| | - M M Rönn
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - T L Gift
- Division of STD Prevention, Centers for Disease Control and Prevention, Atlanta, Georgia, USA
| | - J A Salomon
- Department of Health Policy, Stanford University School of Medicine, Stanford, CA, USA
| | - Y H Grad
- Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, Massachusetts, USA
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Martin SL, Mortimer TD, Grad YH. Machine learning models for Neisseria gonorrhoeae antimicrobial susceptibility tests. Ann N Y Acad Sci 2023; 1520:74-88. [PMID: 36573759 PMCID: PMC9974846 DOI: 10.1111/nyas.14549] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Neisseria gonorrhoeae is an urgent public health threat due to the emergence of antibiotic resistance. As most isolates in the United States are susceptible to at least one antibiotic, rapid molecular antimicrobial susceptibility tests (ASTs) would offer the opportunity to tailor antibiotic therapy, thereby expanding treatment options. With genome sequence and antibiotic resistance phenotype data for nearly 20,000 clinical N. gonorrhoeae isolates now available, there is an opportunity to use statistical methods to develop sequence-based diagnostics that predict antibiotic susceptibility from genotype. N. gonorrhoeae, therefore, provides a useful example illustrating how to apply machine learning models to aid in the design of sequence-based ASTs. We present an overview of this framework, which begins with establishing the assay technology, the performance criteria, the population in which the diagnostic will be used, and the clinical goals, and extends to the choices that must be made to arrive at a set of features with the desired properties for predicting susceptibility phenotype from genotype. While we focus on the example of N. gonorrhoeae, the framework generalizes to other organisms for which large-scale genotype and antibiotic resistance data can be combined to aid in diagnostics development.
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Affiliation(s)
- Skylar L. Martin
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Tatum D. Mortimer
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
| | - Yonatan H. Grad
- Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, Massachusetts, USA
- Division of Infectious Diseases, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Scangarella-Oman NE, Hossain M, Perry CR, Tiffany C, Powell M, Swift B, Dumont EF. Dose selection for a phase III study evaluating gepotidacin (GSK2140944) in the treatment of uncomplicated urogenital gonorrhoea. Sex Transm Infect 2023; 99:64-69. [PMID: 36411033 PMCID: PMC9887395 DOI: 10.1136/sextrans-2022-055518] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 09/30/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Gepotidacin is a novel, first-in-class triazaacenaphthylene antibiotic that inhibits bacterial DNA replication by a distinct mechanism of action and is active against most strains of Neisseria gonorrhoeae (N. gonorrhoeae). Phase II data suggested higher exposures were needed for efficacy and to suppress resistance development. A translational approach using in vitro pharmacokinetic/pharmacodynamic (PK/PD) and clinical data was used to select a gepotidacin dose for a phase III study. In this narrative review of previously shown data, we summarise how a translational approach based on in vitro PK/PD and population PK modelling and simulation data was undertaken to select a dosing regimen for the ongoing phase III gepotidacin study in participants with uncomplicated urogenital gonorrhoea. METHODS For dose selection, prior in vitro minimum inhibitory concentrations (MICs) and PK/PD data were available. PK modelling was conducted to determine a dose that would limit plasma concentrations to less than 14 µg/mL (as concentrations above this are associated with QT prolongation and effects associated with acetylcholinesterase inhibition) while maintaining ≥90% probability of target attainment (PTA) for efficacy and resistance suppression against N. gonorrhoeae isolates with gepotidacin MICs ≤1 µg/mL. RESULTS Two 3000 mg gepotidacin doses, administered 10-12 hours apart, resulted in PTA of ≥97.5% and ≥91.7% for gepotidacin MICs ≤1 µg/mL for the ratio of the area under the free drug plasma concentration-time curve over 24 hours to the MIC (fAUC0-24/MIC) efficacy, and resistance suppression targets of 40 and 46, respectively, but limited the occurrence of maximum plasma concentrations ≥14 µg/mL. CONCLUSIONS Two gepotidacin 3000 mg oral doses 10-12 hours apart provide ~2-fold higher systemic exposures, increase efficacy for higher gepotidacin MIC N. gonorrhoeae isolates, reduce resistance potential and limit plasma concentrations of potential safety concern, compared with higher doses.
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Affiliation(s)
| | | | | | | | - Marcy Powell
- GSK, Research Triangle Park, North Carolina, USA
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White PJ, Nikitin D, Whittles LK. We need estimates of gonorrhoea vaccine protection and symptomaticity by sex and anatomical site. THE LANCET. INFECTIOUS DISEASES 2022; 22:937. [PMID: 35752179 DOI: 10.1016/s1473-3099(22)00343-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Accepted: 05/17/2022] [Indexed: 11/15/2022]
Affiliation(s)
- Peter J White
- Medical Research Council Centre for Global Infectious Disease Analysis and National Institute for Health and Care Research Health Protection Research Unit in Modelling and Health Economics, Imperial College London, London W2 1PG, UK; Modelling and Economics Unit, UK Health Security Agency, London, UK.
| | - Dariya Nikitin
- Medical Research Council Centre for Global Infectious Disease Analysis and National Institute for Health and Care Research Health Protection Research Unit in Modelling and Health Economics, Imperial College London, London W2 1PG, UK
| | - Lilith K Whittles
- Medical Research Council Centre for Global Infectious Disease Analysis and National Institute for Health and Care Research Health Protection Research Unit in Modelling and Health Economics, Imperial College London, London W2 1PG, UK
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Lu Y, Mann CA, Nolan S, Collins JA, Parker E, Papa J, Vibhute S, Jahanbakhsh S, Thwaites M, Hufnagel D, Hazbón MH, Moreno J, Stedman TT, Wittum T, Wozniak DJ, Osheroff N, Yalowich JC, Mitton-Fry MJ. 1,3-Dioxane-Linked Novel Bacterial Topoisomerase Inhibitors: Expanding Structural Diversity and the Antibacterial Spectrum. ACS Med Chem Lett 2022; 13:955-963. [PMID: 35707162 PMCID: PMC9189870 DOI: 10.1021/acsmedchemlett.2c00111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Accepted: 05/05/2022] [Indexed: 11/29/2022] Open
Abstract
Antibacterial resistance continues its devastation of available therapies. Novel bacterial topoisomerase inhibitors (NBTIs) offer one solution to this critical issue. Two series of amine NBTIs bearing tricyclic DNA-binding moieties as well as amide NBTIs with a bicyclic DNA-binding moiety were synthesized and evaluated against methicillin-resistant Staphylococcus aureus (MRSA). Additionally, these compounds and a series of bicyclic amine analogues displayed high activity against susceptible and drug-resistant Neisseria gonorrhoeae, expanding the spectrum of these dioxane-linked NBTIs.
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Affiliation(s)
- Yanran Lu
- Division
of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Chelsea A. Mann
- Division
of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Sheri Nolan
- Microbial
Infection and Immunity, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jessica A. Collins
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
| | - Elizabeth Parker
- Department
of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Jonathan Papa
- Division
of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Sandip Vibhute
- Division
of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | | | | | | | | | - Jane Moreno
- ATCC, Manassas, Virginia 20110, United States
| | | | - Thomas Wittum
- Department
of Veterinary Preventive Medicine, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210, United States
| | - Daniel J. Wozniak
- Microbial
Infection and Immunity, College of Medicine, The Ohio State University, Columbus, Ohio 43210, United States
- Department
of Microbiology, College of Arts and Sciences, The Ohio State University, Columbus, Ohio 43210, United States
| | - Neil Osheroff
- Department
of Biochemistry, Vanderbilt University School
of Medicine, Nashville, Tennessee 37232, United States
- Department
of Medicine (Hematology/Oncology), Vanderbilt
University School of Medicine, Nashville, Tennessee 37232, United States
- VA Tennessee Valley Healthcare System, Nashville, Tennessee 37212, United States
| | - Jack C. Yalowich
- Division
of Pharmaceutics and Pharmacology, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
| | - Mark J. Mitton-Fry
- Division
of Medicinal Chemistry and Pharmacognosy, College of Pharmacy, The Ohio State University, Columbus, Ohio 43210, United States
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Phin N, Poutanen SM. The cat is out of the bag - point-of-care testing (POCT) is here to stay. Euro Surveill 2020; 25:2001854. [PMID: 33153521 PMCID: PMC7645973 DOI: 10.2807/1560-7917.es.2020.25.44.2001854] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 11/20/2022] Open
Affiliation(s)
- Nick Phin
- Public Health England (PHE), Colindale, London, United Kingdom
- University of Chester, Chester, United Kingdom
| | - Susan M Poutanen
- University Health Network/Sinai Health Department of Microbiology, Toronto, Canada
- Department of Laboratory Medicine and Pathobiology, Department of Medicine, University of Toronto, Toronto, Canada
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