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1.
Diagnostics (Basel) ; 12(5)2022 May 19.
Article in English | MEDLINE | ID: covidwho-1928513

ABSTRACT

The COVID-19 pandemic has unveiled a pressing need to expand the diagnostic landscape to permit high-volume testing in peak demand. Rapid nucleic acid testing based on isothermal amplification is a viable alternative to real-time reverse transcription polymerase chain reaction (RT-PCR) and can help close this gap. With the emergence of SARS-CoV-2 variants of concern, clinical validation of rapid molecular tests needs to demonstrate their ability to detect known variants, an essential requirement for a robust pan-SARS-CoV-2 assay. To date, there has been no clinical validation of reverse transcription recombinase polymerase amplification (RT-RPA) assays for SARS-CoV-2 variants. We performed a clinical validation of a one-pot multi-gene RT-RPA assay with the E and RdRP genes of SARS-CoV-2 as targets. The assay was validated with 91 nasopharyngeal samples, with a full range of viral loads, collected at University College London Hospitals. Moreover, the assay was tested with previously sequenced clinical samples, including eleven lineages of SARS-CoV-2. The rapid (20 min) RT-RPA assay showed high sensitivity and specificity, equal to 96% and 97%, respectively, compared to gold standard real-time RT-PCR. The assay did not show cross-reactivity with the panel of respiratory pathogens tested. We also report on a semi-quantitative analysis of the RT-RPA results with correlation to viral load equivalents. Furthermore, the assay could detect all eleven SARS-CoV-2 lineages tested, including four variants of concern (Alpha, Beta, Delta, and Omicron). This variant-proof SARS-CoV-2 assay offers a significantly faster and simpler alternative to RT-PCR, delivering sensitive and specific results with clinical samples.

2.
Front Public Health ; 10: 829715, 2022.
Article in English | MEDLINE | ID: covidwho-1792879

ABSTRACT

Objectives: To investigate the impact of cannabis use on the infection and survival outcomes of COVID-19. Study Design: Cross-sectional study based on the UK Biobank (UKB) dataset. Methods: We identified 13,099 individuals with cannabis smoking history in the UKB COVID-19 Serology Study. The Charlson-Quan Comorbidity Index was estimated using inpatient ICD-10 records. Multivariable logistic regression characterized features associated with COVID-19 infection. Cox models determined the hazard ratios (HR) for COVID-19-related survival. Results: Cannabis users were more likely to getting COVID-19 (odds ratio: 1.22, P = 0.001) but multivariable analysis showed that cannabis use was a protective factor of COVID-19 infection (adjusted odds ratio: 0.81, P = 0.001). Regular cannabis users, who smoked more than once per month, had a significantly poorer COVID-19-related survival, after adjusting for known risk factors including age, gender, smoking history, and comorbidity (adjusted hazard ratio: 2.81, P = 0.041). Conclusions: The frequency of cannabis use could be considered as a candidate predictor for mortality risk of COVID-19.


Subject(s)
COVID-19 , Cannabis , Marijuana Smoking , COVID-19/epidemiology , Comorbidity , Cross-Sectional Studies , Humans , Marijuana Smoking/epidemiology
3.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-308234

ABSTRACT

Background: As of July 24 2020, the global reported number of COVID-19 cases was > 15.4 millions, with over 640,000 deaths. The present study aimed to carry out an epidemiological analysis of confirmed cases and asymptomatic infections in Shenzhen City to provide scientific reference for the prevention and control of COVID-19. Methods The epidemiological information of the 462 confirmed cases and 45 asymptomatic infections from January 19th to June 30th was collected in Shenzhen City, Southern China, and a descriptive analysis was performed. Results A total of 462 confirmed COVID-19 cases from January 19 to April 30, 2020 were reported in Shenzhen City, including 423 domestic cases (91.56%) and 39 imported cases (8.44%) who came back from other countries. Among domestic cases, the majority were cases imported from Hubei Province (n = 312, 67.53%), followed by local ones (n = 69, 14.94%). During the same period, a total of 45 asymptomatic infections were reported in Shenzhen City, including 31 local ones (68.89%) and 14 imported from abroad (31.11%). The proportion of asymptomatic infections in Shenzhen City was increasing over time (Z = 13.1888, P  < 0.0001). The total number of local asymptomatic infections in Shenzhen City exceeded as the same pattern as that in other provinces ( χ 2  = 118.830, P  < 0.0001). The proportion of asymptomatic infections among cases imported from abroad was higher than that of the same in domestic cases ( χ 2  = 22.5121, P  < 0.0001, OR  = 4.8983, 95%: 2.4052, 9.9756). No statistical significance was noted in the proportions of asymptomatic infections among imported cases from different countries ( χ 2  = 7.7202, P  = 0.6561). Conclusions The majority of COVID-19 cases in Shenzhen City were imported cases who came back from Hubei Province in the early stage (before 1st March, 2020) and from abroad in the later stage (after 1st April, 2020). Scientific and effective prevention and control measures have resulted in only a few local infections in Shenzhen City. Asymptomatic infections accounted for an increasing proportion among cases imported from abroad, indicating that the prevention measures carried out in Shenzhen City did avoid the import of infected cases. Improving the detection capability to identify asymptomatic infections as early as possible will be of significance for the control outbreak of COVID-19.

4.
Infect Dis Ther ; 10(4): 2431-2446, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1505773

ABSTRACT

INTRODUCTION: As a homologue of the angiotensin-converting enzyme (ACE), angiotensin-converting enzyme 2 (ACE2) has been identified as the main receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) invasion. We aimed to investigate the role of serum ACE in predicting the coronavirus disease 2019 (COVID-19) disease progression and the underlying mechanisms. METHODS: We retrospectively enrolled 120 patients with confirmed COVID-19 who underwent serum ACE detection on admission. The clinical characteristics and laboratory findings during hospitalization were evaluated dynamically to identify the potential risk factors for disease progression. RESULTS: ACE level was demonstrated as one of the independent risk factors. Patients with ACE level ≤ 33.5 U/L showed a higher cumulative virus RNA detection rate, elevated pro-inflammatory mediators levels, declined lymphocyte count, and decreased SARS-CoV-2-specific antibodies than those with ACE level > 33.5 U/L. CONCLUSION: Lower serum ACE levels in relation to delayed virus elimination, hyperinflammatory condition, and impaired host antiviral immune responses contribute to disease progression of COVID-19.

6.
Chemical Engineering Journal ; : 131902, 2021.
Article in English | ScienceDirect | ID: covidwho-1363115

ABSTRACT

Developing green and highly efficient water disinfection technique is of great importance to public health. Herein, a near-infrared (NIR) light-triggerable thermo-sensitive defective molybdenum oxide-nitrogen doped carbon (MoO3-x/NCNs) composite was fabricated and applied to water disinfection. With the synergy of photodynamic and photothermal effects, the MoO3-x/NCNs achieve a rapid and effective inactivation of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as compared to photocatalytic treatment or thermal catalytic alone. Particularly, MONC-3 with optimal ratio can completely inactivate 7.6 log of E. coli and S. aureus within 60 min and 100 min, respectively. The MONC-3 hybrid exhibits efficient charge separation and migration ability due to the formation of Schottky heterojunction, resulting in the highly enhanced ·O2– (11.34×10-10 M) generation activity. Meanwhile, excellent NIR light absorption and photothermal conversion efficiency (52.6%) of MONC-3 can generate local high temperature to promote photocatalytic reaction rate and destruct the bacterial integrity. The monitoring of cell damage process confirmed the irreversible death of bacteria. Based on density functional theory (DFT) calculation, the antibacterial mechanism and Schottky effect were clarified. This work provides new insights for constructing a water disinfection strategy based on plasma-induced photothermal synergy catalysis.

7.
Biosens Bioelectron ; 189: 113328, 2021 Oct 01.
Article in English | MEDLINE | ID: covidwho-1230375

ABSTRACT

The COVID-19 pandemic is challenging diagnostic testing capacity worldwide. The mass testing needed to limit the spread of the virus requires new molecular diagnostic tests to dramatically widen access at the point-of-care in resource-limited settings. Isothermal molecular assays have emerged as a promising technology, given the faster turn-around time and minimal equipment compared to gold standard laboratory PCR methods. However, unlike PCR, they do not typically target multiple SARS-CoV-2 genes, risking sensitivity and specificity. Moreover, they often require multiple steps thus adding complexity and delays. Here we develop a multiplexed, 1-2 step, fast (20-30 min) SARS-CoV-2 molecular test using reverse transcription recombinase polymerase amplification to simultaneously detect two conserved targets - the E and RdRP genes. The agile multi-gene platform offers two complementary detection methods: real-time fluorescence or dipstick. The analytical sensitivity of the fluorescence test was 9.5 (95% CI: 7.0-18) RNA copies per reaction for the E gene and 17 (95% CI: 11-93) RNA copies per reaction for the RdRP gene. The analytical sensitivity for the dipstick method was 130 (95% CI: 82-500) RNA copies per reaction. High specificity was found against common seasonal coronaviruses, SARS-CoV and MERS-CoV model samples. The dipstick readout demonstrated potential for point-of-care testing in decentralised settings, with minimal or equipment-free incubation methods and a user-friendly prototype smartphone application. This rapid, simple, ultrasensitive and multiplexed molecular test offers valuable advantages over gold standard tests and in future could be configurated to detect emerging variants of concern.


Subject(s)
Biosensing Techniques , COVID-19 , Humans , Molecular Diagnostic Techniques , Nucleic Acid Amplification Techniques , Pandemics , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction , Recombinases/genetics , SARS-CoV-2 , Sensitivity and Specificity
8.
Zhongguo Bingdubing Zazhi = Chinese Journal of Viral Diseases ; - (1):61, 2021.
Article in English | ProQuest Central | ID: covidwho-1184255

ABSTRACT

Coronavirus disease 2019 (COVID-19) is an acute respiratory infectious disease caused by a novel coronavirus (severe acute respiratory syndrome coronavirus 2, SARS-CoV-2) infection, and its spread speed Fast, the crowd is generally susceptible [1]. AIDS (acquired immune deficiency syndrome, AIDS) is caused by human immunodeficiency virus (human immunodeficiency virus).

10.
J Med Virol ; 93(5): 2805-2809, 2021 05.
Article in English | MEDLINE | ID: covidwho-891891

ABSTRACT

The emerging pandemic of coronavirus disease 2019 (COVID-19) has affected over 200 countries and resulted in a shortage of diagnostic resources globally. Rapid diagnosis of COVID-19 is vital to control the spreading of the disease, which, however, is challenged by limited detection capacity and low detection efficiency in many parts of the world. The pooling test may offer an economical and effective approach to increase the virus testing capacity of medical laboratories without requiring more laboratory resources such as laboratory workers, testing reagents, and equipment. In this study, the sample pools of 6 and 10 were detected by a real-time reverse transcription-polymerase chain reaction assay targeting ORF1ab and N genes of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Each pool consisted of five or nine negative SARS-CoV-2 samples and one positive counterpart with varying viral loads. Two different strategies of sample pooling were investigated and the results were compared comprehensively. One approach was to pool the viral transport medium of the samples in the laboratory, and the other was to pool swab samples during the collection process. For swab pooling strategy, qualitative results of SARS-CoV-2 RNA, specific tests of ORF1ab and N genes, remained stable over the different pool sizes. Together, this study demonstrates that the swab pooling strategy may serve as an effective and economical approach for screening SARS-CoV-2 infections in large populations, especially in countries and regions where medical resources are limited during the pandemic and may thus be potential for clinical laboratory applications.


Subject(s)
COVID-19 Testing/methods , COVID-19/diagnosis , RNA, Viral/isolation & purification , SARS-CoV-2/genetics , SARS-CoV-2/isolation & purification , COVID-19 Nucleic Acid Testing/methods , Coronavirus Nucleocapsid Proteins/genetics , Diagnostic Tests, Routine/methods , Humans , Mass Screening/methods , Phosphoproteins/genetics , Polyproteins/genetics , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/methods , Specimen Handling/methods , Viral Load , Viral Proteins/genetics
11.
J Clin Invest ; 130(5): 2620-2629, 2020 05 01.
Article in English | MEDLINE | ID: covidwho-98087

ABSTRACT

BACKGROUNDSince December 2019, an outbreak of coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in Wuhan, and is now becoming a global threat. We aimed to delineate and compare the immunological features of severe and moderate COVID-19.METHODSIn this retrospective study, the clinical and immunological characteristics of 21 patients (17 male and 4 female) with COVID-19 were analyzed. These patients were classified as severe (11 cases) and moderate (10 cases) according to the guidelines released by the National Health Commission of China.RESULTSThe median age of severe and moderate cases was 61.0 and 52.0 years, respectively. Common clinical manifestations included fever, cough, and fatigue. Compared with moderate cases, severe cases more frequently had dyspnea, lymphopenia, and hypoalbuminemia, with higher levels of alanine aminotransferase, lactate dehydrogenase, C-reactive protein, ferritin, and D-dimer as well as markedly higher levels of IL-2R, IL-6, IL-10, and TNF-α. Absolute numbers of T lymphocytes, CD4+ T cells, and CD8+ T cells decreased in nearly all the patients, and were markedly lower in severe cases (294.0, 177.5, and 89.0 × 106/L, respectively) than moderate cases (640.5, 381.5, and 254.0 × 106/L, respectively). The expression of IFN-γ by CD4+ T cells tended to be lower in severe cases (14.1%) than in moderate cases (22.8%).CONCLUSIONThe SARS-CoV-2 infection may affect primarily T lymphocytes, particularly CD4+ and CD8+ T cells, resulting in a decrease in numbers as well as IFN-γ production by CD4+ T cells. These potential immunological markers may be of importance because of their correlation with disease severity in COVID-19.TRIAL REGISTRATIONThis is a retrospective observational study without a trial registration number.FUNDINGThis work is funded by grants from Tongji Hospital for the Pilot Scheme Project, and partly supported by the Chinese National Thirteenth Five Years Project in Science and Technology for Infectious Disease (2017ZX10202201).


Subject(s)
Coronavirus Infections/immunology , Coronavirus Infections/pathology , Cytokines/blood , Cytokines/immunology , Pneumonia, Viral/immunology , Pneumonia, Viral/pathology , T-Lymphocytes/immunology , Adult , Aged , COVID-19 , Cell Count , China , Coronavirus Infections/blood , Coronavirus Infections/diagnostic imaging , Female , Gene Expression Profiling , Gene Expression Regulation/immunology , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/blood , Pneumonia, Viral/diagnostic imaging , Retrospective Studies , Severity of Illness Index
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