Catalogue Search | MBRL
Search Results Heading
Explore the vast range of titles available.
MBRLSearchResults
-
DisciplineDiscipline
-
Is Peer ReviewedIs Peer Reviewed
-
Item TypeItem Type
-
SubjectSubject
-
YearFrom:-To:
-
More FiltersMore FiltersSourceLanguage
Done
Filters
Reset
388
result(s) for
"Leung, Gabriel M"
Sort by:
Estimating clinical severity of COVID-19 from the transmission dynamics in Wuhan, China
2020
As of 29 February 2020 there were 79,394 confirmed cases and 2,838 deaths from COVID-19 in mainland China. Of these, 48,557 cases and 2,169 deaths occurred in the epicenter, Wuhan. A key public health priority during the emergence of a novel pathogen is estimating clinical severity, which requires properly adjusting for the case ascertainment rate and the delay between symptoms onset and death. Using public and published information, we estimate that the overall symptomatic case fatality risk (the probability of dying after developing symptoms) of COVID-19 in Wuhan was 1.4% (0.9–2.1%), which is substantially lower than both the corresponding crude or naïve confirmed case fatality risk (2,169/48,557 = 4.5%) and the approximator
1
of deaths/deaths + recoveries (2,169/2,169 + 17,572 = 11%) as of 29 February 2020. Compared to those aged 30–59 years, those aged below 30 and above 59 years were 0.6 (0.3–1.1) and 5.1 (4.2–6.1) times more likely to die after developing symptoms. The risk of symptomatic infection increased with age (for example, at ~4% per year among adults aged 30–60 years).
An estimation of the clinical severity of COVID-19, based on the data available so far, can help to inform the public health response during the ongoing SARS-CoV-2 pandemic.
Journal Article
Depression and post-traumatic stress during major social unrest in Hong Kong: a 10-year prospective cohort study
2020
Hong Kong has been embroiled in increasingly violent social unrest since June, 2019. We examined the associated population mental health burden, risk factors, and health-care needs.
In a population-based prospective cohort, adult participants aged 18 years or older were assessed at nine timepoints from 2009. Probable depression was measured using the Patient Health Questionnaire-9 (score ≥10) and suspected post-traumatic stress disorder (PTSD) by the PTSD Checklist—Civilian Version (score ≥14), plus direct exposure to traumatic events related to the ongoing social unrest. We used multivariable logistic regression to identify factors associated with both outcomes, adjusting for doctor-diagnosed depression or anxiety disorders before the unrest. On the basis of routine service statistics and respondents' intention to seek professional care, we projected the number of additional ambulatory specialist psychiatric visits required.
After the two baseline surveys, we followed up random subsets of 1213–1736 adults at each timepoint. Probable depression was reported by 11·2% (95% CI 9·8–12·7) of participants in 2019, compared with 1·9% (1·6–2·1) during 2009–14 and 6·5% (5·3–7·6) in 2017 after the Occupy Central Movement and before the current unrest. Prevalence of suspected PTSD in 2019 was estimated to be 12·8% (11·2–14·4). Age, sex, educational attainment, or household income were not associated with either outcome, whereas heavy social media use (≥2 h per day) was associated with both. Political attitude or protest participation was not associated with probable depression, but neutrality towards the extradition bill approximately halved the risk of suspected PTSD. Family support mitigated against probable depression. We estimated that the mental health burden identified would translate into roughly an excess 12% service requirement to the public sector queue or equivalent.
We have identified a major mental health burden during the social unrest in Hong Kong, which will require substantial increases in service surge capacity. Health-care and social care professionals should be vigilant in recognising possible mental health sequelae. In a world of increasing unrest, our findings might have implications for service planning to better protect population mental health globally.
Research Grants Council, University Grants Committee of Hong Kong, Hong Kong Jockey Club Charities Trust.
Journal Article
Estimating the transmission dynamics of SARS-CoV-2 Omicron BF.7 in Beijing after adjustment of the zero-COVID policy in November–December 2022
by
Leung, Kathy
,
Lau, Eric H. Y.
,
Leung, Gabriel M.
in
692/308/174
,
692/699/255/2514
,
Beijing - epidemiology
2023
We tracked the effective reproduction number (
R
t
) of the predominant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant Omicron BF.7 in Beijing in November–December 2022 by fitting a transmission dynamic model parameterized with real-time mobility data to (i) the daily number of new symptomatic cases on 1–11 November (when China’s zero-COVID interventions were still strictly enforced) and (ii) the proportion of individuals who participated in online polls on 10–22 December and self-reported to have been test-positive since 1 November. After China’s announcement of 20 measures to transition from zero-COVID, we estimated that
R
t
increased to 3.44 (95% credible interval (CrI): 2.82–4.14) on 18 November and the infection incidence peaked on 11 December. We estimated that the cumulative infection attack rate (IAR; that is, proportion of the population infected since 1 November) in Beijing was 75.7% (95% CrI: 60.7–84.4) on 22 December 2022 and 92.3% (95% CrI: 91.4–93.1) on 31 January 2023. Surveillance programs should be rapidly set up to monitor the evolving epidemiology and evolution of SARS-CoV-2 across China.
With the lifting of the zero-COVID policy and requirements governing reporting case numbers in China, it has become imperative to estimate the dynamics and cumulative infection rate of SARS-CoV-2 to help guide public health responses.
Journal Article
Real-time tracking and prediction of COVID-19 infection using digital proxies of population mobility and mixing
by
Leung, Gabriel M.
,
Wu, Joseph T.
,
Leung, Kathy
in
631/114/2397
,
631/114/2415
,
631/326/596/4130
2021
Digital proxies of human mobility and physical mixing have been used to monitor viral transmissibility and effectiveness of social distancing interventions in the ongoing COVID-19 pandemic. We develop a new framework that parameterizes disease transmission models with age-specific digital mobility data. By fitting the model to case data in Hong Kong, we are able to accurately track the local effective reproduction number of COVID-19 in near real time (i.e., no longer constrained by the delay of around 9 days between infection and reporting of cases) which is essential for quick assessment of the effectiveness of interventions on reducing transmissibility. Our findings show that accurate nowcast and forecast of COVID-19 epidemics can be obtained by integrating valid digital proxies of physical mixing into conventional epidemic models.
Digital proxies of human mobility can be used to monitor social distancing, and therefore have potential to infer COVID-19 dynamics. Here, the authors integrate travel card data from Hong Kong into a transmission model and show that it can be used to track transmissibility in near real-time.
Journal Article
Diagnostic performance of different sampling approaches for SARS-CoV-2 RT-PCR testing: a systematic review and meta-analysis
by
Cowling, Benjamin J
,
Leung, Gabriel M
,
So, Hau Chi
in
Accuracy
,
Ambulatory care
,
Coronaviruses
2021
The comparative performance of different clinical sampling methods for diagnosis of SARS-CoV-2 infection by RT-PCR among populations with suspected infection remains unclear. This meta-analysis aims to systematically compare the diagnostic performance of different clinical specimen collection methods.
In this systematic review and meta-analysis, we systematically searched PubMed, Embase, MEDLINE, Web of Science, medRxiv, bioRxiv, SSRN, and Research Square from Jan 1, 2000, to Nov 16, 2020. We included original clinical studies that examined the performance of nasopharyngeal swabs and any additional respiratory specimens for the diagnosis of SARS-CoV-2 infection among individuals presenting in ambulatory care. Studies without data on paired samples, or those that only examined different samples from confirmed SARS-CoV-2 cases were not useful for examining diagnostic performance of a test and were excluded. Diagnostic performance, including sensitivity, specificity, positive predictive value, and negative predictive value, was examined using random effects models and double arcsine transformation.
Of the 5577 studies identified in our search, 23 studies including 7973 participants with 16 762 respiratory samples were included. Respiratory specimens examined in these studies included 7973 nasopharyngeal swabs, 1622 nasal swabs, 6110 saliva samples, 338 throat swabs, and 719 pooled nasal and throat swabs. Using nasopharyngeal swabs as the gold standard, pooled nasal and throat swabs gave the highest sensitivity of 97% (95% CI 93–100), whereas lower sensitivities were achieved by saliva (85%, 75–93) and nasal swabs (86%, 77–93) and a much lower sensitivity by throat swabs (68%, 35–94). A comparably high positive predictive value was obtained by pooled nasal and throat (97%, 90–100) and nasal swabs (96%, 87–100) and a slightly lower positive predictive value by saliva (93%, 88–97). Throat swabs have the lowest positive predictive value of 75% (95% CI 45–96). Comparably high specificities (range 97–99%) and negative predictive value (range 95–99%) were observed among different clinical specimens. Comparison between health-care-worker collection and self-collection for pooled nasal and throat swabs and nasal swabs showed comparable diagnostic performance. No significant heterogeneity was observed in the analysis of pooled nasal and throat swabs and throat swabs, whereas moderate to substantial heterogeneity (I2 ≥30%) was observed in studies on saliva and nasal swabs.
Our review suggests that, compared with the gold standard of nasopharyngeal swabs, pooled nasal and throat swabs offered the best diagnostic performance of the alternative sampling approaches for diagnosis of SARS-CoV-2 infection in ambulatory care. Saliva and nasal swabs gave comparable and very good diagnostic performance and are clinically acceptable alternative specimen collection methods. Throat swabs gave a much lower sensitivity and positive predictive value and should not be recommended. Self-collection for pooled nasal and throat swabs and nasal swabs was not associated with any significant impairment of diagnostic accuracy. Our results also provide a useful reference framework for the proper interpretation of SARS-CoV-2 testing results using different clinical specimens.
Hong Kong Research Grants Council.
Journal Article
Lessons learnt from easing COVID-19 restrictions: an analysis of countries and regions in Asia Pacific and Europe
by
Leung, Gabriel M
,
Asgari, Nima
,
Teo, Yik Ying
in
Analysis
,
Asia, Eastern
,
Clinical decision making
2020
The COVID-19 pandemic is an unprecedented global crisis. Many countries have implemented restrictions on population movement to slow the spread of severe acute respiratory syndrome coronavirus 2 and prevent health systems from becoming overwhelmed; some have instituted full or partial lockdowns. However, lockdowns and other extreme restrictions cannot be sustained for the long term in the hope that there will be an effective vaccine or treatment for COVID-19. Governments worldwide now face the common challenge of easing lockdowns and restrictions while balancing various health, social, and economic concerns. To facilitate cross-country learning, this Health Policy paper uses an adapted framework to examine the approaches taken by nine high-income countries and regions that have started to ease COVID-19 restrictions: five in the Asia Pacific region (ie, Hong Kong [Special Administrative Region], Japan, New Zealand, Singapore, and South Korea) and four in Europe (ie, Germany, Norway, Spain, and the UK). This comparative analysis presents important lessons to be learnt from the experiences of these countries and regions. Although the future of the virus is unknown at present, countries should continue to share their experiences, shield populations who are at risk, and suppress transmission to save lives.
Journal Article
Hand, foot, and mouth disease in China, 2008–12: an epidemiological study
by
Viboud, Cécile
,
Xing, Weijia
,
Leung, Gabriel M
in
Adolescent
,
Age Factors
,
Biological and medical sciences
2014
Hand, foot, and mouth disease is a common childhood illness caused by enteroviruses. Increasingly, the disease has a substantial burden throughout east and southeast Asia. To better inform vaccine and other interventions, we characterised the epidemiology of hand, foot, and mouth disease in China on the basis of enhanced surveillance.
We extracted epidemiological, clinical, and laboratory data from cases of hand, foot, and mouth disease reported to the Chinese Center for Disease Control and Prevention between Jan 1, 2008, and Dec 31, 2012. We then compiled climatic, geographical, and demographic information. All analyses were stratified by age, disease severity, laboratory confirmation status, and enterovirus serotype.
The surveillance registry included 7 200 092 probable cases of hand, foot, and mouth disease (annual incidence, 1·2 per 1000 person-years from 2010–12), of which 267 942 (3·7%) were laboratory confirmed and 2457 (0·03%) were fatal. Incidence and mortality were highest in children aged 12–23 months (38·2 cases per 1000 person-years and 1·5 deaths per 100 000 person-years in 2012). Median duration from onset to diagnosis was 1·5 days (IQR 0·5–2·5) and median duration from onset to death was 3·5 days (2·5–4·5). The absolute number of patients with cardiopulmonary or neurological complications was 82 486 (case-severity rate 1·1%), and 2457 of 82486 patients with severe disease died (fatality rate 3·0%); 1617 of 1737 laboratory confirmed deaths (93%) were associated with enterovirus 71. Every year in June, hand, foot, and mouth disease peaked in north China, whereas southern China had semiannual outbreaks in May and September–October. Geographical differences in seasonal patterns were weakly associated with climate and demographic factors (variance explained 8–23% and 3–19%, respectively).
This is the largest population-based study up to now of the epidemiology of hand, foot, and mouth disease. Future mitigation policies should take into account the heterogeneities of disease burden identified. Additional epidemiological and serological studies are warranted to elucidate the dynamics and immunity patterns of local hand, foot, and mouth disease and to optimise interventions.
China–US Collaborative Program on Emerging and Re-emerging Infectious Diseases, WHO, The Li Ka Shing Oxford Global Health Programme and Wellcome Trust, Harvard Center for Communicable Disease Dynamics, and Health and Medical Research Fund, Government of Hong Kong Special Administrative Region.
Journal Article
Mental Health, Risk Factors, and Social Media Use During the COVID-19 Epidemic and Cordon Sanitaire Among the Community and Health Professionals in Wuhan, China: Cross-Sectional Survey
2020
The mental health consequences of the coronavirus disease (COVID-19) pandemic, community-wide interventions, and social media use during a pandemic are unclear. The first and most draconian interventions have been implemented in Wuhan, China, and these countermeasures have been increasingly deployed by countries around the world.
The aim of this study was to examine risk factors, including the use of social media, for probable anxiety and depression in the community and among health professionals in the epicenter, Wuhan, China.
We conducted an online survey via WeChat, the most widely used social media platform in China, which was administered to 1577 community-based adults and 214 health professionals in Wuhan. Probable anxiety and probable depression were assessed by the validated Generalized Anxiety Disorder-2 (cutoff ≥3) and Patient Health Questionnaire-2 (cutoff ≥3), respectively. A multivariable logistic regression analysis was used to examine factors associated with probable anxiety and probable depression.
Of the 1577 community-based adults, about one-fifth of respondents reported probable anxiety (n=376, 23.84%, 95% CI 21.8-26.0) and probable depression (n=303, 19.21%, 95% CI 17.3-21.2). Similarly, of the 214 health professionals, about one-fifth of surveyed health professionals reported probable anxiety (n=47, 22.0%, 95% CI 16.6-28.1) or probable depression (n=41, 19.2%, 95% CI 14.1-25.1). Around one-third of community-based adults and health professionals spent ≥2 hours daily on COVID-19 news via social media. Close contact with individuals with COVID-19 and spending ≥2 hours daily on COVID-19 news via social media were associated with probable anxiety and depression in community-based adults. Social support was associated with less probable anxiety and depression in both health professionals and community-based adults.
The internet could be harnessed for telemedicine and restoring daily routines, yet caution is warranted toward spending excessive time searching for COVID-19 news on social media given the infodemic and emotional contagion through online social networks. Online platforms may be used to monitor the toll of the pandemic on mental health.
Journal Article
Mental disorders following COVID-19 and other epidemics: a systematic review and meta-analysis
by
Galea, Sandro
,
Leung, Candi M. C.
,
Ni, Michael Y.
in
692/699/476
,
692/699/476/1414
,
Anxiety - epidemiology
2022
COVID-19 has imposed a very substantial direct threat to the physical health of those infected, although the corollary impact on mental health may be even more burdensome. Here we focus on assessing the mental health impact of COVID-19 and of other epidemics in the community. We searched five electronic databases until December 9, 2020, for all peer-reviewed original studies reporting any prevalence or correlates of mental disorders in the general population following novel epidemics in English, Chinese or Portuguese. We synthesised prevalence estimates from probability samples during COVID-19 and past epidemics. The meta-analytical effect size was the prevalence of relevant outcomes, estimated via random-effects model.
I
2
statistics, Doi plots and the LFK index were used to examine heterogeneity and publication bias. This study is pre-registered with PROSPERO, CRD42020179105. We identified 255 eligible studies from 50 countries on: COVID-19 (
n
= 247 studies), severe acute respiratory syndrome (SARS;
n
= 5), Ebola virus disease (
n
= 2), and 1918 influenza (
n
= 1). During COVID-19, we estimated the point prevalence for probable anxiety (20.7%, 95% CI 12.9–29.7), probable depression (18.1%, 13.0–23.9), and psychological distress (13.0%, 0–34.1). Correlates for poorer mental health include female sex, lower income, pre-existing medical conditions, perceived risk of infection, exhibiting COVID-19-like symptoms, social media use, financial stress, and loneliness. Public trust in authorities, availability of accurate information, adoption of preventive measures and social support were associated with less morbidity. The mental health consequences of COVID-19 and other epidemics could be comparable to major disasters and armed conflicts. The considerable heterogeneity in our analysis indicates that more random samples are needed. Health-care professionals should be vigilant of the psychological toll of epidemics, including among those who have not been infected.
Journal Article
Will Ebola change the game? Ten essential reforms before the next pandemic. The report of the Harvard-LSHTM Independent Panel on the Global Response to Ebola
by
Fallah, Mosoka
,
Heymann, David L
,
Jha, Ashish K
in
Africa - epidemiology
,
Communicable Disease Control - organization & administration
,
Disease control
2015
The west African Ebola epidemic that began in 2013 exposed deep inadequacies in the national and international institutions responsible for protecting the public from the far-reaching human, social, economic, and political consequences of infectious disease outbreaks. The Ebola epidemic raised a crucial question: what reforms are needed to mend the fragile global system for outbreak prevention and response, rebuild confidence, and prevent future disasters?
Journal Article