Evaluation of the Rapid Antigen Detection Test for Diagnosing SARS-CoV-2 during the COVID-19 Pandemic: Experience from a Centralized Isolation Site in Shanghai, China.

Rapid and reliable diagnosis is important for the management of individuals infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The rapid antigen detection test (RADT) is a rapid, inexpensive, and easy method. Several studies have reported that RADTs performed well in many countries; however, very few studies have been reported in China. In this study, we assessed the performance of the RADT (Ediagnosis COVID-19 antigen test kit). This study was conducted in a centralized isolation site in Shanghai and enrolled 716 patients with COVID-19 and 203 noninfected participants. Nasopharyngeal swabs from all participants were collected on the same day and tested using the RADT and real-time reverse transcription-PCR (RT-PCR). The performance of the RADT was evaluated in different scenarios, such as threshold cycle (CT) values, symptomatic phase, and symptoms on the day of testing. The results demonstrated that the sensitivity for patients with CT values lower than 20 was 96.55% (95% confidence interval [CI], 87.05 to 99.4). The sensitivities were 78.4% (95% CI, 69.96 to 85.05) for participants within 5 days after the first RT-PCR-positive result and 90.77% (95% CI, 80.34 to 96.19) within 5 days after symptom onset. Moreover, the sensitivity of the RADT was more than 80% for patients with symptoms on the day of testing, including fever (89.29%), cough (86.84%), stuffy nose (92.59%), runny nose (92%), sore throat (81.25%), and muscle pain (80.77%), especially for those with upper respiratory tract symptoms. The specificity of the RADT was good in all scenarios. During the SARS-CoV-2 epidemic, Ediagnosis performed excellently in individuals with a higher viral load (evidenced by lower CT values), individuals in the early symptomatic phase, and especially those with upper respiratory tract symptoms. IMPORTANCE RADTs have demonstrated excellent performance in many counties for screening SARS-CoV-2 infection, but very few studies have been conducted in China. The performance of RADTs is largely related to different real-life scenarios. In our study, the performance of the RADT was evaluated in different scenarios, such as CT values, symptomatic phase, and symptoms on the day of testing. The results demonstrated that Ediagnosis (an RADT made in China) performed excellently for individuals with a higher viral load (evidenced by lower CT values), individuals in the early symptomatic phase, and especially those with upper respiratory tract symptoms.

Determinants of workplace safety towards SARS-Cov-2 and combating COVID-19 among non-healthcare workers in Hong Kong, Nanjing and Wuhan, China.

There has been no validated tool to assess workplace infection control towards SARS-Cov-2 in non-healthcare industries. In this first year survey during 07/2020-04/2021, 6684 workers were recruited from varied non-healthcare settings of Hong Kong, Nanjing and Wuhan of China and responded standard questionnaires containing information of prevention measures and policies implemented by companies and personal preventive behaviour towards infection control. All participants were randomly stratified into two sub-samples as training and validation sample. Workplace safety index towards SARS-Cov-2 (WSI-SC2) was developed and validated using exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). We identified 14 manifest variables in WSI-SC2, with three sub-indices named "Workplace infection control measures and prevention", "Company occupational safety and health management and commitment" and "Worker's personal preventive behavior and awareness towards infectious control". WSI-SC2 obtained a good internal consistency reliability (Cronbach's alpha coefficients ranged: 0.76-0.91), good composite reliability (composite reliability ranged: 0.70-0.95) and satisfactory fit of the model (GFI = 0.95; SRMR = 0.05; RMSEA = 0.07). We further performed stratified analysis according to cities, and the index remained stable. Workers with higher scores of WSI-SC2 were more likely to uptake COVID-19 test. This multi-city large study developed a novel and validated tool that could horizontally measure the workplace safety towards SARS-Cov-2 in non-healthcare workers.

Association of current income and reduction in income during the COVID-19 pandemic with anxiety and depression among non-healthcare workers.

BACKGROUND: Many workers experienced income reduction during the coronavirus disease 2019 (COVID-19) pandemic, which may link to adverse mental health. AIMS: This study aimed to examine the association of current income and reduction in income during COVID-19 with anxiety and depression levels among non-healthcare workers. METHODS: This is a multi-city cross-sectional study. We used standardized questionnaires to collect information. We regrouped the current income and income reduction during COVID-19 according to the tertile and median value of each specific city. Depression, Anxiety and Stress Scales-21 item short version (DASS-21) was used to assess anxiety and depression levels. We performed multinomial logistic regression to examine the association of current and reduced income with anxiety and depression. Path models were developed to outline the potential modification/indirect effect of subsidies from government. RESULTS: Large income reduction and low current income were significantly associated with more anxiety/depression symptoms. Path analysis showed that government subsidies could not significantly alleviate the impact of reduced income on anxiety/depression. CONCLUSION: Our findings showed that large income reduction and low current income were independently associated with anxiety/depression, while these symptoms may not be ameliorated by one-off government funds. This study suggests the need for long-term policies (e.g. developing sustained economic growth policies) to mitigate negative impacts of the COVID-19.

Effect of public health interventions on COVID-19 cases: an observational study.

BACKGROUND: As the epidemic of COVID-19 is gradually controlled in China, a summary of epidemiological characteristics and interventions may help control its global spread. METHODS: Data for COVID-19 cases in Hubei Province (capital, Wuhan) was extracted until 7 March 2020. The spatiotemporal distribution of the epidemic in four periods (before 10 January, 10-22 January, 23 January-6 February and 7 February-7 March) was evaluated, and the impacts of interventions were observed. RESULTS: Among 67 706 COVID-19 cases, 52 111 (76.97%) were aged 30-69 years old, and 34 680 (51.22%) were women. The average daily attack rates (95% CI) were 0.5 (0.3 to 0.7), 14.2 (13.2 to 15.1), 45.7 (44.0 to 47.5) and 8.6 (7.8 to 9.3) cases per 106 people in four periods, and the harmonic means (95% CI) of doubling times were 4.28 (4.01 to 4.55), 3.87 (3.78 to 3.98), 5.40 (4.83 to 6.05) and 45.56 (39.70 to 52.80) days. Compared with the first period, daily attack rates rose rapidly in the second period. In the third period, 14 days after 23 January, the daily average attack rate in and outside Wuhan declined by 33.8% and 48.0%; the doubling times increased by 95.0% and 133.2%. In the four periods, 14 days after 7 February, the daily average attack rate in and outside Wuhan decreased by 79.1% and 95.2%; the doubling times increased by 79.2% and 152.0%. CONCLUSIONS: The public health interventions were associated with a reduction in COVID-19 cases in Hubei Province, especially in districts outside of Wuhan.

Spatiotemporal analysis of COVID-19 outbreaks in Wuhan, China.

Few study has revealed spatial transmission characteristics of COVID-19 in Wuhan, China. We aimed to analyze the spatiotemporal spread of COVID-19 in Wuhan and its influence factors. Information of 32,682 COVID-19 cases reported through March 18 were extracted from the national infectious disease surveillance system. Geographic information system methods were applied to analysis transmission of COVID-19 and its influence factors in different periods. We found decrease in effective reproduction number (Rt) and COVID-19 related indicators through taking a series of effective public health measures including restricting traffic, centralized quarantine and strict stay-at home policy. The distribution of COVID-19 cases number in Wuhan showed obvious global aggregation and local aggregation. In addition, the analysis at streets-level suggested population density and the number of hospitals were associated with COVID-19 cases number. The epidemic situation showed obvious global and local spatial aggregations. High population density with larger number of hospitals may account for the aggregations. The epidemic in Wuhan was under control in a short time after strong quarantine measures and restrictions on movement of residents were implanted.

Epidemiological characteristics and transmission dynamics of paediatric cases with coronavirus disease 2019 in Hubei province, China.

AIM: This study aimed to identify the epidemiological characteristics and transmission dynamics of paediatric cases. METHODS: Information on 1369 paediatric cases with COVID-19 from 8 December 2019 to 7 March 2020 in Hubei province was extracted from the National Infectious Disease Surveillance System. The analysis included epidemic curves, temporal-spatial distribution, clinical classification and interval times between onset and diagnosis. RESULTS: Among 1369 paediatric cases, the median age was 9 years and 58.2% of them were males. The proportion of severe and critical cases in children was lower than that in adults and the proportion of asymptomatic cases in children was five times greater than for adult cases. The first paediatric case was reported on 2 January 2020, and the daily number of new paediatric cases remained high from 1 February through to 22 February. The epidemiological curve of paediatric cases lagged behind that of adults by 19 days, and the first spike of the epidemic curve in senior high school students occurred 1 week earlier than in other paediatric groups. The proportion of clustered cases among children was about twice that for adults. The median of the interval in paediatric cases between onset and diagnosis, isolation and notification were 3, 0 and 3 days, respectively, and all of those were significantly shorter than in adults. CONCLUSIONS: The epidemic curve of child cases lagged behind that of adult cases by 19 days, and the major form of transmission observed was in clusters.

Epidemiological characteristics and the entire evolution of coronavirus disease 2019 in Wuhan, China.

BACKGROUND: Coronavirus Disease 2019 (COVID-19) spread rapidly around the world. We aimed to describe the epidemiological characteristics and the entire evolution of COVID-19 in Wuhan, and to evaluate the effect of non-pharmaceutical intervention by the government. METHODS: The information of COVID-19 cases until Mar 18, 2020 in Wuhan were collected from the national infectious disease surveillance system in Hubei province. RESULTS: A total of 49,973 confirmed cases were reported until Mar 18, 2020 in Wuhan. Among whom, 2496 cases died and the overall mortality was 5.0%. Most confirmed cases (25,619, 51.3%) occurred during Jan 23 to Feb 4, with a spike on Feb 1 (new cases, 3374). The number of daily new cases started to decrease steadily on Feb 19 (new cases, 301) and decreased greatly on Mar 1 (new cases, 57). However, the mortality and the proportion of severe and critical cases has been decreasing over time, with the lowest of 2.0 and 10.1% during Feb 16 to Mar 18, 2020, respectively. The percentage of severe and critical cases among all cases was 19.6%, and the percentage of critical and dead cases aged over 60 was 70.1 and 82.0%, respectively. CONCLUSION: The number of new cases has dropped significantly after the government taking the isolation of four types of personnel and the community containment for 14 days. Our results indicate that the mortality and proportion of severe and critical cases gradually decreased over time, and critical and dead cases are more incline to be older individuals.

Epidemiological Characteristics and Incubation Period of 7015 Confirmed Cases With Coronavirus Disease 2019 Outside Hubei Province in China.

BACKGROUND: Disease caused by SARS-CoV-2 broke out in Wuhan in December 2019. We utilized confirmed cases outside Hubei Province to analyze epidemiologic characteristics and evaluate the effect of traffic restrictions implemented in Hubei beginning on 23 January 2020. METHODS: Information on 7015 confirmed cases from 19 January to 8 February 2020 in all provinces outside Hubei was collected from the national and local health commissions in China. Incubation period and interval times were calculated using dates of the following events: contact with an infected person, onset, first visit, and diagnosis. We evaluated changes in incubation period and interval times. RESULTS: The average age of all cases was 44.24 years. The median incubation period was 5 days and extended from 2 days on 23 January to 15 days on 8 February. The proportion of imported cases decreased from 85.71% to 33.19% after 23 January. In addition, lengths of intervals between onset and diagnosis, onset and first visit, and first visit and diagnosis decreased over time. CONCLUSIONS: Rapidly transmitting COVID-19 has a short incubation period. The onset mainly occurred among young to middle-aged adults. Traffic restrictions played an important role in the decreased number of imported cases outside Hubei.