BackgroundWe assessed the preferences and trade-offs for social interactions, incentives, and bei... more BackgroundWe assessed the preferences and trade-offs for social interactions, incentives, and being traced by a digital contact tracing (DCT) tool post lockdown in Singapore.MethodsWe conducted a discrete choice experiment (DCE) among visitors of a large public hospital in Singapore between July 2020 – February 2021. Respondents were sampled proportionately by gender and four age categories (21 – 80 years). The DCE questionnaire had three attributes (1. Social interactions, 2. Being traced by a DCT tool, 3. Incentives to use a DCT tool) and two levels each. The final dataset comprised 3839 respondents after dropping 53 with “irrational” responses. Panel fixed conditional logit model was used to analyze the data.ResultsRespondents were more willing to trade being traced by a DCT tool for social interactions than incentives and unwilling to trade social interactions for incentives. The proportion of respondents preferring no incentives and could only be influenced by their family memb...
Title: Mapping infectious disease hospital surge threats to lessons learnt in Singapore: A system... more Title: Mapping infectious disease hospital surge threats to lessons learnt in Singapore: A systems analysis and development of a framework to inform how to DECIDE on planning and response strategies Authors: Shweta Singh (shweta@nuhs.edu.sg) Richard Coker (richard.coker@lshtm.ac.uk) Hubertus Vrijhoef (vrijhoef_hubertus@nuhs.edu.sg) Yee Sin Leo (yee_sin_leo@ttsh.com.sg) Angela Chow (angela_chow@ttsh.com.sg) Poh Lian Lim (poh_lian_lim@ttsh.com.sg) Qinghui Tan (tan_qing_hui@brc.a-star.edu.sg) Mark I-Cheng Chen (mark_chen@nuhs.edu.sg) Zoe Hildon (Zhildon1@jhu.edu) Version: 1 Date: 16 Jul 2017 Author’s response to reviews: We thank the reviewers for their positive comments and helpful critical feedback and endeavor to address these carefully. To avoid confusing track changes, we track using this mode while excluding deletions and format changes and index the changes using comments linking to the numbered (reviewer 1a-i and reviewer 2a-o) points below. NB: Please note my Primary Affiliati...
Antimicrobial stewardship programmes (ASPs) in hospitals are predominantly led by specific ASP ph... more Antimicrobial stewardship programmes (ASPs) in hospitals are predominantly led by specific ASP physicians and pharmacists. Limited studies have been conducted to appreciate non-ASP-trained hospital pharmacists’ perspectives on their roles in antimicrobial stewardship. Focus group discussions (FGDs) were conducted with 74 pharmacists, purposively sampled from the 3 largest acute-care public hospitals in Singapore, to explore facilitators and barriers faced by them in antimicrobial stewardship. Applied thematic analysis was conducted and codes were categorised using the social–ecological model (SEM). At the intrapersonal level, pharmacists identified themselves as reviewers for drug safety before dispensing, confining to a restricted advisory role due to lack of clinical knowledge, experience, and empowerment to contribute actively to physicians’ prescribing decisions. At the interpersonal level, pharmacists expressed difficulties conveying their opinions and recommendations on antibi...
Objective Real-time locating systems (RTLS) enable contact tracing and hand hygiene reminders, to... more Objective Real-time locating systems (RTLS) enable contact tracing and hand hygiene reminders, to improve hospital safety. Successful implementation requires healthcare personnel (HCP) to carry RTLS tags continuously. We assessed for determinants of HCP’s willingness to use RTLS tags during routine inpatient care, and evaluated concerns using mixed-methods analysis. Materials and Methods We conducted a cross-sectional study in the 330-bed purpose-built National Centre for Infectious Diseases in Singapore, from January 15 through February 4, 2020. The anonymous survey comprised 24 questions based on constructs from behavioral models and an open-ended question. Principal component analysis was performed to derive the latent factor structure applied in the multivariable logistic regression analysis. Concerns were analyzed using thematic analysis. Results Of 260 HCP (nurses [40.8%], ancillary and administrative staff [23.1%], allied health professionals [18.5%], and physicians [17.7%]),...
Background Appropriate antibiotic prescribing is key to combating antimicrobial resistance. Upper... more Background Appropriate antibiotic prescribing is key to combating antimicrobial resistance. Upper respiratory tract infections (URTIs) are common reasons for emergency department (ED) visits and antibiotic use. Differentiating between bacterial and viral infections is not straightforward. We aim to provide an evidence-based clinical decision support tool for antibiotic prescribing using prediction models developed from local data. Methods Seven hundred-fifteen patients with uncomplicated URTI were recruited and analysed from Singapore’s busiest ED, Tan Tock Seng Hospital, from June 2016 to November 2018. Confirmatory tests were performed using the multiplex polymerase chain reaction (PCR) test for respiratory viruses and point-of-care test for C-reactive protein. Demographic, clinical and laboratory data were extracted from the hospital electronic medical records. Seventy percent of the data was used for training and the remaining 30% was used for validation. Decision trees, LASSO a...
BACKGROUND Effective contact tracing is labor intensive and time sensitive during the COVID-19 pa... more BACKGROUND Effective contact tracing is labor intensive and time sensitive during the COVID-19 pandemic, but also essential in the absence of effective treatment and vaccines. Singapore launched the first Bluetooth-based contact tracing app—TraceTogether—in March 2020 to augment Singapore’s contact tracing capabilities. OBJECTIVE This study aims to compare the performance of the contact tracing app—TraceTogether—with that of a wearable tag-based real-time locating system (RTLS) and to validate them against the electronic medical records at the National Centre for Infectious Diseases (NCID), the national referral center for COVID-19 screening. METHODS All patients and physicians in the NCID screening center were issued RTLS tags (CADI Scientific) for contact tracing. In total, 18 physicians were deployed to the NCID screening center from May 10 to May 20, 2020. The physicians activated the TraceTogether app (version 1.6; GovTech) on their smartphones during shifts and urged their pat...
Objective: Overuse of antibiotics in the emergency department (ED) for uncomplicated acute respir... more Objective: Overuse of antibiotics in the emergency department (ED) for uncomplicated acute respiratory tract infections (uARTIs) is a public health issue that needs to be addressed. We aimed to identify factors associated with antibiotic use for uARTIs in adults presenting at the ED. Design: We searched Medline, Embase, PsycINFO and the Cochrane Library for articles published from 1 January 2005 to 30 June 2017 using a predetermined search strategy. Titles and abstracts of English articles on antibiotic prescription and inappropriate antibiotic use for adult ARTI at EDs were assessed, followed by full article review, by 2 authors. Setting: Emergency departments. Participants: Adults aged 18 years and older. Results: Of the 2,591 articles retrieved, 12 articles met the inclusion criteria and 11 studies were conducted in the United States. Patients with normal C-reactive protein levels and positive influenza tests were less likely to receive antibiotic treatment. Nonclinical factors a...
Background Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by novel ... more Background Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by novel coronavirus (SARS-CoV-2), and first reported in Wuhan, China, in December 2019. Since the severe acute respiratory syndrome (SARS) outbreak in 2003, Tan Tock Seng Hospital (TTSH) in Singapore has routinely fit-tested staff for high filtration N95 respirators, and established web-based staff surveillance systems. The routine systems were enhanced in response to Singapore’s first imported COVID-19 case on January 23,2020. Methods We conducted a cross-sectional study, from January 23,2020 to February 23,2020, among healthcare workers to evaluate the effectiveness of the staff protection and surveillance strategy in TTSH, a 1600-bed multidisciplinary acute-care hospital co-located with the 330-bed National Centre for Infectious Diseases (NCID). As of February 23,2020, TTSH/NCID has managed 76% of confirmed COVID-19 cases in Singapore. The hospital adopted a multi-pronged approach to protect ...
Background: Streptococcus pneumoniae infections can lead to severe morbidity and mortality, espec... more Background: Streptococcus pneumoniae infections can lead to severe morbidity and mortality, especially in patients with invasive pneumococcal disease (IPD). This study evaluated factors associated with pneumococcal disease, pneumococcal vaccine effectiveness, and risk factors for mortality among hospitalised adults with pneumococcal disease in Singapore. Methods: Retrospective case-cohort study of patients tested for pneumococcal disease with streptococcal urinary antigen testing and at least one sterile site culture, during their admission to a tertiary hospital in Singapore from 2015-2017. Patients were defined as cases of IPD or non-IPD, or as controls, based on laboratory results and clinical diagnoses. Multivariable models were constructed to determine factors associated with IPD/non-IPD, and risk factors for mortality from pneumococcal disease. Vaccine effectiveness against IPD/non-IPD was estimated using a variation of the test-negative design. Results: We identified 496 pneu...
Upper respiratory tract infections (URTIs) account for substantial attendances at emergency depar... more Upper respiratory tract infections (URTIs) account for substantial attendances at emergency departments (EDs). There is a need to elucidate determinants of antibiotic prescribing in time-strapped EDs – popular choices for primary care despite highly accessible primary care clinics. Semi-structured in-depth interviews were conducted with purposively sampled physicians (n = 9) in an adult ED in Singapore. All interviews were analysed using thematic analysis and further interpreted using the Social Ecological Model to explain prescribing determinants. Themes included: (1) reliance on clinical knowledge and judgement, (2) patient-related factors, (3) patient–physician relationship factors, (4) perceived practice norms, (5) policies and treatment guidelines and (6) patient education and awareness. The physicians relied strongly on their clinical knowledge and judgement in managing URTI cases and seldom interfered with their peers’ clinical decisions. Despite departmental norms of not pre...
Intranasal octenidine, an antiseptic alternative to mupirocin, can be used for methicillin-resist... more Intranasal octenidine, an antiseptic alternative to mupirocin, can be used for methicillin-resistant Staphylococcus aureus (MRSA) decolonisation in the prevention of nosocomial transmission. A controlled before-after study was conducted in three extended-care hospitals in Singapore. All inpatients with >48 h stay were screened for MRSA colonisation in mid-2015(pre-intervention) and mid-2016(post-intervention). Hospital A: universal daily chlorhexidine bathing throughout 2015 and 2016, with intranasal octenidine for MRSA-colonisers in 2016. Hospital B: universal daily octenidine bathing and intranasal octenidine for MRSA-colonisers in 2016. Hospital C: no intervention. In 2015, MRSA prevalence was similar among the hospitals (Hospital A: 38.5%, Hospital B: 48.1%, Hospital C: 43.4%, P = 0.288). From 2015 to 2016, MRSA prevalence reduced by 58% in Hospital A (Adj OR 0.42, 95% CI 0.20-0.89) and 43% in Hospital B (Adj OR 0.57, 95% CI 0.39-0.84), but remained similar in Hospital C (Adj...
The first autochthonous Zika virus (ZIKV) outbreak in Singapore was detected in August 2016. We r... more The first autochthonous Zika virus (ZIKV) outbreak in Singapore was detected in August 2016. We report an analysis of the correlation of clinical illness with viremia and laboratory parameters in this Asian cohort. We conducted a prospective longitudinal cohort study of patients with a positive blood ZIKV polymerase chain reaction (PCR) result who were admitted to Tan Tock Seng Hospital, Singapore, for isolation and management. We included 40 patients in our study. Rash was present in all patients, while 80% (32/40) had fever, 62.5% (25/40) myalgia, 60% (24/40) conjunctivitis and 38% (15/40) arthralgia. The median duration of viremia was 3.5 days (IQR: 3-5 days). Patients with viremia of ≥4 days were more likely to have prolonged fever compared to those with viremia of less than 4 days (95% versus 63%, p = 0.01), but had no significant correlation with other clinical signs and symptoms, or laboratory investigations. However, 21 patients (53%) had hypokalemia despite the absence of g...
Dengue virus and Zika virus coexist in tropical regions in Asia where healthcare resources are li... more Dengue virus and Zika virus coexist in tropical regions in Asia where healthcare resources are limited; differentiating the 2 viruses is challenging. We showed in a case-control discovery cohort, and replicated in a validation cohort, that the diagnostic indices of conjunctivitis, platelet count, and monocyte count reliably distinguished between these viruses.
BackgroundWe assessed the preferences and trade-offs for social interactions, incentives, and bei... more BackgroundWe assessed the preferences and trade-offs for social interactions, incentives, and being traced by a digital contact tracing (DCT) tool post lockdown in Singapore.MethodsWe conducted a discrete choice experiment (DCE) among visitors of a large public hospital in Singapore between July 2020 – February 2021. Respondents were sampled proportionately by gender and four age categories (21 – 80 years). The DCE questionnaire had three attributes (1. Social interactions, 2. Being traced by a DCT tool, 3. Incentives to use a DCT tool) and two levels each. The final dataset comprised 3839 respondents after dropping 53 with “irrational” responses. Panel fixed conditional logit model was used to analyze the data.ResultsRespondents were more willing to trade being traced by a DCT tool for social interactions than incentives and unwilling to trade social interactions for incentives. The proportion of respondents preferring no incentives and could only be influenced by their family memb...
Title: Mapping infectious disease hospital surge threats to lessons learnt in Singapore: A system... more Title: Mapping infectious disease hospital surge threats to lessons learnt in Singapore: A systems analysis and development of a framework to inform how to DECIDE on planning and response strategies Authors: Shweta Singh (shweta@nuhs.edu.sg) Richard Coker (richard.coker@lshtm.ac.uk) Hubertus Vrijhoef (vrijhoef_hubertus@nuhs.edu.sg) Yee Sin Leo (yee_sin_leo@ttsh.com.sg) Angela Chow (angela_chow@ttsh.com.sg) Poh Lian Lim (poh_lian_lim@ttsh.com.sg) Qinghui Tan (tan_qing_hui@brc.a-star.edu.sg) Mark I-Cheng Chen (mark_chen@nuhs.edu.sg) Zoe Hildon (Zhildon1@jhu.edu) Version: 1 Date: 16 Jul 2017 Author’s response to reviews: We thank the reviewers for their positive comments and helpful critical feedback and endeavor to address these carefully. To avoid confusing track changes, we track using this mode while excluding deletions and format changes and index the changes using comments linking to the numbered (reviewer 1a-i and reviewer 2a-o) points below. NB: Please note my Primary Affiliati...
Antimicrobial stewardship programmes (ASPs) in hospitals are predominantly led by specific ASP ph... more Antimicrobial stewardship programmes (ASPs) in hospitals are predominantly led by specific ASP physicians and pharmacists. Limited studies have been conducted to appreciate non-ASP-trained hospital pharmacists’ perspectives on their roles in antimicrobial stewardship. Focus group discussions (FGDs) were conducted with 74 pharmacists, purposively sampled from the 3 largest acute-care public hospitals in Singapore, to explore facilitators and barriers faced by them in antimicrobial stewardship. Applied thematic analysis was conducted and codes were categorised using the social–ecological model (SEM). At the intrapersonal level, pharmacists identified themselves as reviewers for drug safety before dispensing, confining to a restricted advisory role due to lack of clinical knowledge, experience, and empowerment to contribute actively to physicians’ prescribing decisions. At the interpersonal level, pharmacists expressed difficulties conveying their opinions and recommendations on antibi...
Objective Real-time locating systems (RTLS) enable contact tracing and hand hygiene reminders, to... more Objective Real-time locating systems (RTLS) enable contact tracing and hand hygiene reminders, to improve hospital safety. Successful implementation requires healthcare personnel (HCP) to carry RTLS tags continuously. We assessed for determinants of HCP’s willingness to use RTLS tags during routine inpatient care, and evaluated concerns using mixed-methods analysis. Materials and Methods We conducted a cross-sectional study in the 330-bed purpose-built National Centre for Infectious Diseases in Singapore, from January 15 through February 4, 2020. The anonymous survey comprised 24 questions based on constructs from behavioral models and an open-ended question. Principal component analysis was performed to derive the latent factor structure applied in the multivariable logistic regression analysis. Concerns were analyzed using thematic analysis. Results Of 260 HCP (nurses [40.8%], ancillary and administrative staff [23.1%], allied health professionals [18.5%], and physicians [17.7%]),...
Background Appropriate antibiotic prescribing is key to combating antimicrobial resistance. Upper... more Background Appropriate antibiotic prescribing is key to combating antimicrobial resistance. Upper respiratory tract infections (URTIs) are common reasons for emergency department (ED) visits and antibiotic use. Differentiating between bacterial and viral infections is not straightforward. We aim to provide an evidence-based clinical decision support tool for antibiotic prescribing using prediction models developed from local data. Methods Seven hundred-fifteen patients with uncomplicated URTI were recruited and analysed from Singapore’s busiest ED, Tan Tock Seng Hospital, from June 2016 to November 2018. Confirmatory tests were performed using the multiplex polymerase chain reaction (PCR) test for respiratory viruses and point-of-care test for C-reactive protein. Demographic, clinical and laboratory data were extracted from the hospital electronic medical records. Seventy percent of the data was used for training and the remaining 30% was used for validation. Decision trees, LASSO a...
BACKGROUND Effective contact tracing is labor intensive and time sensitive during the COVID-19 pa... more BACKGROUND Effective contact tracing is labor intensive and time sensitive during the COVID-19 pandemic, but also essential in the absence of effective treatment and vaccines. Singapore launched the first Bluetooth-based contact tracing app—TraceTogether—in March 2020 to augment Singapore’s contact tracing capabilities. OBJECTIVE This study aims to compare the performance of the contact tracing app—TraceTogether—with that of a wearable tag-based real-time locating system (RTLS) and to validate them against the electronic medical records at the National Centre for Infectious Diseases (NCID), the national referral center for COVID-19 screening. METHODS All patients and physicians in the NCID screening center were issued RTLS tags (CADI Scientific) for contact tracing. In total, 18 physicians were deployed to the NCID screening center from May 10 to May 20, 2020. The physicians activated the TraceTogether app (version 1.6; GovTech) on their smartphones during shifts and urged their pat...
Objective: Overuse of antibiotics in the emergency department (ED) for uncomplicated acute respir... more Objective: Overuse of antibiotics in the emergency department (ED) for uncomplicated acute respiratory tract infections (uARTIs) is a public health issue that needs to be addressed. We aimed to identify factors associated with antibiotic use for uARTIs in adults presenting at the ED. Design: We searched Medline, Embase, PsycINFO and the Cochrane Library for articles published from 1 January 2005 to 30 June 2017 using a predetermined search strategy. Titles and abstracts of English articles on antibiotic prescription and inappropriate antibiotic use for adult ARTI at EDs were assessed, followed by full article review, by 2 authors. Setting: Emergency departments. Participants: Adults aged 18 years and older. Results: Of the 2,591 articles retrieved, 12 articles met the inclusion criteria and 11 studies were conducted in the United States. Patients with normal C-reactive protein levels and positive influenza tests were less likely to receive antibiotic treatment. Nonclinical factors a...
Background Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by novel ... more Background Coronavirus disease 2019 (COVID-19) is an emerging infectious disease caused by novel coronavirus (SARS-CoV-2), and first reported in Wuhan, China, in December 2019. Since the severe acute respiratory syndrome (SARS) outbreak in 2003, Tan Tock Seng Hospital (TTSH) in Singapore has routinely fit-tested staff for high filtration N95 respirators, and established web-based staff surveillance systems. The routine systems were enhanced in response to Singapore’s first imported COVID-19 case on January 23,2020. Methods We conducted a cross-sectional study, from January 23,2020 to February 23,2020, among healthcare workers to evaluate the effectiveness of the staff protection and surveillance strategy in TTSH, a 1600-bed multidisciplinary acute-care hospital co-located with the 330-bed National Centre for Infectious Diseases (NCID). As of February 23,2020, TTSH/NCID has managed 76% of confirmed COVID-19 cases in Singapore. The hospital adopted a multi-pronged approach to protect ...
Background: Streptococcus pneumoniae infections can lead to severe morbidity and mortality, espec... more Background: Streptococcus pneumoniae infections can lead to severe morbidity and mortality, especially in patients with invasive pneumococcal disease (IPD). This study evaluated factors associated with pneumococcal disease, pneumococcal vaccine effectiveness, and risk factors for mortality among hospitalised adults with pneumococcal disease in Singapore. Methods: Retrospective case-cohort study of patients tested for pneumococcal disease with streptococcal urinary antigen testing and at least one sterile site culture, during their admission to a tertiary hospital in Singapore from 2015-2017. Patients were defined as cases of IPD or non-IPD, or as controls, based on laboratory results and clinical diagnoses. Multivariable models were constructed to determine factors associated with IPD/non-IPD, and risk factors for mortality from pneumococcal disease. Vaccine effectiveness against IPD/non-IPD was estimated using a variation of the test-negative design. Results: We identified 496 pneu...
Upper respiratory tract infections (URTIs) account for substantial attendances at emergency depar... more Upper respiratory tract infections (URTIs) account for substantial attendances at emergency departments (EDs). There is a need to elucidate determinants of antibiotic prescribing in time-strapped EDs – popular choices for primary care despite highly accessible primary care clinics. Semi-structured in-depth interviews were conducted with purposively sampled physicians (n = 9) in an adult ED in Singapore. All interviews were analysed using thematic analysis and further interpreted using the Social Ecological Model to explain prescribing determinants. Themes included: (1) reliance on clinical knowledge and judgement, (2) patient-related factors, (3) patient–physician relationship factors, (4) perceived practice norms, (5) policies and treatment guidelines and (6) patient education and awareness. The physicians relied strongly on their clinical knowledge and judgement in managing URTI cases and seldom interfered with their peers’ clinical decisions. Despite departmental norms of not pre...
Intranasal octenidine, an antiseptic alternative to mupirocin, can be used for methicillin-resist... more Intranasal octenidine, an antiseptic alternative to mupirocin, can be used for methicillin-resistant Staphylococcus aureus (MRSA) decolonisation in the prevention of nosocomial transmission. A controlled before-after study was conducted in three extended-care hospitals in Singapore. All inpatients with >48 h stay were screened for MRSA colonisation in mid-2015(pre-intervention) and mid-2016(post-intervention). Hospital A: universal daily chlorhexidine bathing throughout 2015 and 2016, with intranasal octenidine for MRSA-colonisers in 2016. Hospital B: universal daily octenidine bathing and intranasal octenidine for MRSA-colonisers in 2016. Hospital C: no intervention. In 2015, MRSA prevalence was similar among the hospitals (Hospital A: 38.5%, Hospital B: 48.1%, Hospital C: 43.4%, P = 0.288). From 2015 to 2016, MRSA prevalence reduced by 58% in Hospital A (Adj OR 0.42, 95% CI 0.20-0.89) and 43% in Hospital B (Adj OR 0.57, 95% CI 0.39-0.84), but remained similar in Hospital C (Adj...
The first autochthonous Zika virus (ZIKV) outbreak in Singapore was detected in August 2016. We r... more The first autochthonous Zika virus (ZIKV) outbreak in Singapore was detected in August 2016. We report an analysis of the correlation of clinical illness with viremia and laboratory parameters in this Asian cohort. We conducted a prospective longitudinal cohort study of patients with a positive blood ZIKV polymerase chain reaction (PCR) result who were admitted to Tan Tock Seng Hospital, Singapore, for isolation and management. We included 40 patients in our study. Rash was present in all patients, while 80% (32/40) had fever, 62.5% (25/40) myalgia, 60% (24/40) conjunctivitis and 38% (15/40) arthralgia. The median duration of viremia was 3.5 days (IQR: 3-5 days). Patients with viremia of ≥4 days were more likely to have prolonged fever compared to those with viremia of less than 4 days (95% versus 63%, p = 0.01), but had no significant correlation with other clinical signs and symptoms, or laboratory investigations. However, 21 patients (53%) had hypokalemia despite the absence of g...
Dengue virus and Zika virus coexist in tropical regions in Asia where healthcare resources are li... more Dengue virus and Zika virus coexist in tropical regions in Asia where healthcare resources are limited; differentiating the 2 viruses is challenging. We showed in a case-control discovery cohort, and replicated in a validation cohort, that the diagnostic indices of conjunctivitis, platelet count, and monocyte count reliably distinguished between these viruses.
Uploads
Papers by angela chow