Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 19 de 19
Filter
1.
Emerg Microbes Infect ; 11(1): 1550-1553, 2022 Dec.
Article in English | MEDLINE | ID: covidwho-1860765

ABSTRACT

In order to overcome the pandemic of COVID-19, messenger RNA (mRNA)-based vaccine has been extensively researched as a rapid and versatile strategy. Herein, we described the immunogenicity of mRNA-based vaccines for Beta and the most recent Omicron variants. The homologous mRNA-Beta and mRNA-Omicron and heterologous Ad5-nCoV plus mRNA vaccine exhibited high-level cross-reactive neutralization for Beta, original, Delta, and Omicron variants. It indicated that the COVID-19 mRNA vaccines have great potential in the clinical use against different SARS-CoV-2 variants.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/prevention & control , Humans , RNA, Messenger/genetics , SARS-CoV-2/genetics , Vaccines, Synthetic
2.
Biosaf Health ; 2022 May 07.
Article in English | MEDLINE | ID: covidwho-1821155

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to evolve, generating new variants that pose a threat to global health; therefore, it is imperative to obtain safe and broad-spectrum antivirals against SARS-CoV-2 and its variants. To this end, we screened compounds for their ability to inhibit viral entry, which is a critical step in virus infection. Twenty compounds that have been previously reported to inhibit SARS-CoV-2 replication were tested by using pseudoviruses containing the spike protein from the original Wuhan lineage (SARS-CoV-2-WH01). The cytotoxicity of these compounds was determined. Furthermore, we identified six compounds with strong antagonistic activity against the WH01 pseudovirus, and low cytotoxicity was identified. These compounds were then evaluated for their efficacy against pseudoviruses expressing the spike protein from B.1.617.2 (Delta) and B.1.1.529 (Omicron), the two most prevalent circulating strains. These assays demonstrated that two phenothiazine compounds, trifluoperazine 2HCl, and thioridazine HCl, inhibit the infection of Delta and Omicron pseudoviruses. Finally, we discovered that these two compounds were highly effective against authentic SARS-CoV-2 viruses, including the WH01, Delta, and Omicron strains. Our study identified potential broad-spectrum SARS-CoV-2 inhibitors and provided insight into the development of novel therapeutics.

3.
Pathogens ; 11(4)2022 Apr 10.
Article in English | MEDLINE | ID: covidwho-1785869

ABSTRACT

During the COVID-19 pandemic, many general hospitals have been transformed into designated infectious disease care facilities, where a large number of patients with COVID-19 infections have been treated and discharged. With declines in the number of hospitalizations, a major question for our healthcare systems, especially for these designated facilities, is how to safely resume hospital function after these patients have been discharged. Here, we take a designated COVID-19-care facility in Wuhan, China, as an example to share our experience in resuming hospital function while ensuring the safety of patients and medical workers. After more than 1200 patients with COVID-19 infections were discharged in late March, 2020, our hospital resumed function by setting up a three-level hospital infection management system with four grades of risk of exposure. Moreover, we also took measures to ensure the safety of medical personnel in different departments including clinics, wards, and operation rooms. After all patients with COVID-19 infections were discharged, during the five months of regular function from April to September in 2020, no positive cases have been found among more than 40,000 people in our hospital, including hospital staff and patients.

4.
Lancet Microbe ; 3(5): e348-e356, 2022 05.
Article in English | MEDLINE | ID: covidwho-1758021

ABSTRACT

Background: The memory immune response is crucial for preventing reinfection or reducing disease severity. However, the robustness and functionality of the humoral and T-cell response to SARS-CoV-2 remains unknown 12 months after initial infection. The aim of this study is to investigate the durability and functionality of the humoral and T-cell response to the original SARS-CoV-2 strain and variants in recovered patients 12 months after infection. Methods: In this longitudinal cohort study, we recruited participants who had recovered from COVID-19 and who were discharged from the Wuhan Research Center for Communicable Disease Diagnosis and Treatment at the Chinese Academy of Medical Sciences, Wuhan, China, between Jan 7 and May 29, 2020. Patients received a follow-up visit between Dec 16, 2020, and Jan 27, 2021. We evaluated the presence of IgM, IgA, and IgG antibodies against the SARS-CoV-2 nucleoprotein, Spike protein, and the receptor-binding domain 12 months after initial infection, using ELISA. Neutralising antibodies against the original SARS-CoV-2 strain, and the D614G, beta (B.1.351), and delta (B.1.617.2) variants were analysed using a microneutralisation assay in a subset of plasma samples. We analysed the magnitude and breadth of the SARS-CoV-2-specific memory T-cell responses using the interferon γ (IFNγ) enzyme-linked immune absorbent spot (ELISpot) assay and intracellular cytokine staining (ICS) assay. The antibody response and T-cell response (ie, IFN-γ, interleukin-2 [IL-2], and tumour necrosis factor α [TNFα]) were analysed by age and disease severity. Antibody titres were also analysed according to sequelae symptoms. Findings: We enrolled 1096 patients, including 289 (26·4%) patients with moderate initial disease, 734 (67·0%) with severe initial disease, and 73 (6·7%) with critical initial disease. Paired plasma samples were collected from 141 patients during the follow-up visits for the microneutralisation assay. PBMCs were collected from 92 of 141 individuals at the 12-month follow-up visit, of which 80 were analysed by ELISpot and 92 by ICS assay to detect the SARS-CoV-2-specific memory T-cell responses. N-IgG (899 [82·0%]), S-IgG (1043 [95·2%]), RBD-IgG (1032 [94·2%]), and neutralising (115 [81·6%] of 141) antibodies were detectable 12 months after initial infection in most individuals. Neutralising antibodies remained stable 6 and 12 months after initial infection in most individuals younger than 60 years. Multifunctional T-cell responses were detected for all SARS-CoV-2 viral proteins tested. There was no difference in the magnitude of T-cell responses or cytokine profiles in individuals with different symptom severity. Moreover, we evaluated both antibody and T-cell responses to the D614G, beta, and delta viral strains. The degree of reduced in-vitro neutralising antibody responses to the D614G and delta variants, but not to the beta variant, was associated with the neutralising antibody titres after SARS-CoV-2 infection. We also found poor neutralising antibody responses to the beta variant; 83 (72·2%) of 115 patients showed no response at all. Moreover, the neutralising antibody titre reduction of the recovered patient plasma against the delta variant was similar to that of the D614G variant and lower than that of the beta variant. By contrast, T-cell responses were cross-reactive to the beta variant in most individuals. Importantly, T-cell responses could be detected in all individuals who had lost the neutralising antibody response to SARS-CoV-2 12 months after the initial infection. Interpretation: SARS-CoV-2-specific neutralising antibody and T-cell responses were retained 12 months after initial infection. Neutralising antibodies to the D614G, beta, and delta viral strains were reduced compared with those for the original strain, and were diminished in general. Memory T-cell responses to the original strain were not disrupted by new variants. This study suggests that cross-reactive SARS-CoV-2-specific T-cell responses could be particularly important in the protection against severe disease caused by variants of concern whereas neutralising antibody responses seem to reduce over time. Funding: Chinese Academy of Medical Sciences, National Natural Science Foundation, and UK Medical Research Council.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/epidemiology , Cohort Studies , Cytokines , Humans , Immunoglobulin G , Longitudinal Studies , T-Lymphocytes
5.
Chin Med J (Engl) ; 133(9): 1015-1024, 2020 May 05.
Article in English | MEDLINE | ID: covidwho-1722617

ABSTRACT

BACKGROUND: Human infections with zoonotic coronaviruses (CoVs), including severe acute respiratory syndrome (SARS)-CoV and Middle East respiratory syndrome (MERS)-CoV, have raised great public health concern globally. Here, we report a novel bat-origin CoV causing severe and fatal pneumonia in humans. METHODS: We collected clinical data and bronchoalveolar lavage (BAL) specimens from five patients with severe pneumonia from Wuhan Jinyintan Hospital, Hubei province, China. Nucleic acids of the BAL were extracted and subjected to next-generation sequencing. Virus isolation was carried out, and maximum-likelihood phylogenetic trees were constructed. RESULTS: Five patients hospitalized from December 18 to December 29, 2019 presented with fever, cough, and dyspnea accompanied by complications of acute respiratory distress syndrome. Chest radiography revealed diffuse opacities and consolidation. One of these patients died. Sequence results revealed the presence of a previously unknown ß-CoV strain in all five patients, with 99.8% to 99.9% nucleotide identities among the isolates. These isolates showed 79.0% nucleotide identity with the sequence of SARS-CoV (GenBank NC_004718) and 51.8% identity with the sequence of MERS-CoV (GenBank NC_019843). The virus is phylogenetically closest to a bat SARS-like CoV (SL-ZC45, GenBank MG772933) with 87.6% to 87.7% nucleotide identity, but is in a separate clade. Moreover, these viruses have a single intact open reading frame gene 8, as a further indicator of bat-origin CoVs. However, the amino acid sequence of the tentative receptor-binding domain resembles that of SARS-CoV, indicating that these viruses might use the same receptor. CONCLUSION: A novel bat-borne CoV was identified that is associated with severe and fatal respiratory disease in humans.


Subject(s)
Betacoronavirus , Coronavirus Infections/virology , Pneumonia, Viral/virology , Adult , Aged , Betacoronavirus/genetics , Betacoronavirus/isolation & purification , COVID-19 , Coronavirus Infections/diagnostic imaging , Coronavirus Infections/therapy , Female , Humans , Male , Middle Aged , Pandemics , Pneumonia, Viral/diagnostic imaging , Pneumonia, Viral/therapy , SARS-CoV-2 , Tomography, X-Ray , Treatment Outcome
6.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-315274

ABSTRACT

The efficacy of corticosteroids in the treatment of patients with severe COVID-19 remains unknown. We evaluated the impact of corticosteroids on clinical improvement among severe COVID-19 patients. In this retrospective, two-centered, cohort study, we enrolled 101 patients with severe COVID-19: with 39 patients in the steroid group and 63 patients in the non-steroid group. The primary endpoint was Time to Clinical Improvement (TTCI) by up to 28 days after the treatment. Secondary endpoints included the rate of CAT scan improvement, the percentage of negative SARS-Cov-2 RT-PCR tests by Day 28, and the time to discharge. We found that patients in the steroid group did not have significant differences of TTCI from patients in the non-steroid group by 28 days after the treatment (median, 19 days vs. 20 days;hazard ratio, 1.07;p=0.797). The CAT scan improvement rate was not statistically different between the two groups by Day 28 (87.2% vs. 79.0%, p=0.170). The negative test of SARS-CoV2 RT-PCR by Day 28 was 68.4% in the steroid group, 87.1% in the non-steroid group (p= 0.060). Time to discharge was significantly longer in the steroid group than the non-steroid group (35 days vs 21 days, p=0.005). Our findings indicated the short-term corticosteroid at a low to moderate dose did not improve the clinical outcomes for patients with severe COVID-19. Further randomized clinical trials are needed to confirm the findings.

7.
EuropePMC; 2020.
Preprint in English | EuropePMC | ID: ppcovidwho-308223

ABSTRACT

Background: Novel coronavirus (COVID-19) is a new viral species that causes pneumonia. Currently, RT-PCR and IgM/IgG antibody assays have been recommended for the diagnosis of COVID-19 infection. However, the correlation between RT-PCR status and antibody (IgG, IgM) response remains unknown. Methods: : Consecutive COVID-19 patients admitted to our department between February 10, 2020 and March 10, 2020, were diagnosed by guidelines issued by the World Health Organization (WHO) and included in this study. RT-PCR and antibody (IgM/IgG) assays for COVID-19 infection were performed for all patients according to the manufactures’ protocols. Other data, such as demographic, clinical, laboratory, as well as treatment and outcome, were collected using data collection tables from electronic medical records. Results: : During the study period, a total of 103 patients were diagnosed as having a moderate type of COVID-19 at our department, including 55 males and 48 females, with an average age of 57.53 ± 1.65 years old (range 23 to 90 years old). The peak level of SARS-CoV-2 IgM antibody (243.10 ± 89.84 AU/ml) was reported 4 days after the negative RT-PCR (-) (all P < 0.05). Subsequently, the IgM decreased to 42.69 ± 22.39 AU/ml 21 days after RT-PCR (-). However, the IgG was maintained at a high level 4 days before RT-PCR (-) and later. The lymphocyte count was at the lowest level on day7 before the RT-PCR(-) result (P<0.05), and then elevated after RT-PCR conversion (viral clearance). Conclusions: : SARS-CoV-2 IgM/IgG levels did not correlate with RT-PCR status in our study sample. We found that SARS-CoV-2 IgM/IgG could be a potential biomarker to monitor clinical course, determine discharge, and assess recovery of those infected patients with the novel coronavirus. Trial registration: A prospective, open label, randomized, control trial for chloroquine or hydroxychloroquine in patients with mild and common novel coronavirus pulmonary (COVIP-19). ChiCTR2000030054. Registered 18 Feb,2020. http://www.chictr.org.cn/edit.aspx?pid=49869&htm=4

8.
Signal Transduct Target Ther ; 7(1): 44, 2022 02 09.
Article in English | MEDLINE | ID: covidwho-1683982

ABSTRACT

The wide transmission and host adaptation of SARS-CoV-2 have led to the rapid accumulation of mutations, posing significant challenges to the effectiveness of vaccines and therapeutic antibodies. Although several neutralizing antibodies were authorized for emergency clinical use, convalescent patients derived natural antibodies are vulnerable to SARS-CoV-2 Spike mutation. Here, we describe the screen of a panel of SARS-CoV-2 receptor-binding domain (RBD) targeted nanobodies (Nbs) from a synthetic library and the design of a biparatopic Nb, named Nb1-Nb2, with tight affinity and super-wide neutralization breadth against multiple SARS-CoV-2 variants of concern. Deep-mutational scanning experiments identify the potential binding epitopes of the Nbs on the RBD and demonstrate that biparatopic Nb1-Nb2 has a strong escape-resistant feature against more than 60 tested RBD amino acid substitutions. Using pseudovirion-based and trans-complementation SARS-CoV-2 tools, we determine that the Nb1-Nb2 broadly neutralizes multiple SARS-CoV-2 variants at sub-nanomolar levels, including Alpha (B.1.1.7), Beta (B.1.351), Gamma (P.1), Delta (B.1.617.2), Lambda (C.37), Kappa (B.1.617.1), and Mu (B.1.621). Furthermore, a heavy-chain antibody is constructed by fusing the human IgG1 Fc to Nb1-Nb2 (designated as Nb1-Nb2-Fc) to improve its neutralization potency, yield, stability, and potential half-life extension. For the new Omicron variant (B.1.1.529) that harbors unprecedented multiple RBD mutations, Nb1-Nb2-Fc keeps a firm affinity (KD < 1.0 × 10-12 M) and strong neutralizing activity (IC50 = 1.46 nM for authentic Omicron virus). Together, we developed a tetravalent biparatopic human heavy-chain antibody with ultrapotent and broad-spectrum SARS-CoV-2 neutralization activity which highlights the potential clinical applications.


Subject(s)
Antibodies, Neutralizing/pharmacology , Antibodies, Viral/pharmacology , Immunoglobulin Fc Fragments/pharmacology , Recombinant Fusion Proteins/pharmacology , SARS-CoV-2/drug effects , Single-Domain Antibodies/pharmacology , Antibodies, Neutralizing/biosynthesis , Antibodies, Neutralizing/genetics , Antibodies, Viral/biosynthesis , Antibodies, Viral/genetics , Antibody Affinity , Enzyme-Linked Immunosorbent Assay , Epitopes/chemistry , Epitopes/immunology , Escherichia coli/genetics , Escherichia coli/metabolism , Gene Expression , Humans , Immunoglobulin Fc Fragments/biosynthesis , Immunoglobulin Fc Fragments/genetics , Models, Molecular , Neutralization Tests , Protein Binding/drug effects , Protein Conformation , Protein Interaction Domains and Motifs , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/genetics , SARS-CoV-2/growth & development , SARS-CoV-2/immunology , Single-Domain Antibodies/biosynthesis , Single-Domain Antibodies/genetics , Spike Glycoprotein, Coronavirus/antagonists & inhibitors , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology
10.
Inorg Chem Commun ; 134: 108995, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1458846

ABSTRACT

In recent decades, the use of engineered nanoparticles has been increasing in various sectors, including biomedicine, diagnosis, water treatment, and environmental remediation leading to significant public concerns. Among these nanoparticles, magnetic nanoparticles (MNPs) have gained many attentions in medicine, pharmacology, drug delivery system, molecular imaging, and bio-sensing due to their various properties. In addition, various studies have reviewed MNPs main applications in the biomedical engineering area with intense progress and recent achievements. Nanoparticles, especially the magnetic nanoparticles, have recently been confirmed with excellent antiviral activity against different viruses, including SARS-CoV-2(Covid-19) and their recent development against Covid-19 also has also been discussed. This review aims to highlight the recent development of the magnetic nanoparticles and their biomedical applications such as diagnosis of diseases, molecular imaging, hyperthermia, bio-sensing, gene therapy, drug delivery and the diagnosis of Covid-19.

11.
Biosaf Health ; 3(5): 238-243, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1401267

ABSTRACT

Many factors have been identified as having the ability to affect the sensitivity of rapid antigen detection (RAD) tests for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study aimed to identify the impact of sample processing on the sensitivity of the RAD tests. We explored the effect of different inactivation methods, viral transport media (VTM) solutions, and sample preservation on the sensitivity of four RAD kits based on two SARS-CoV-2 strains. Compared with non-inactivation, heat inactivation significantly impacted the sensitivity of most RAD kits; however, ß-propiolactone inactivation only had a minor effect. Some of the VTM solutions (VTM2, MANTACC) had a significant influence on the sensitivity of the RAD kits, especially for low viral-loads samples. The detection value of RAD kits was slightly decreased, while most of them were still in the detection range with the extension of preservation time and the increase of freeze-thaw cycles. Our results showed that selecting the appropriate inactivation methods and VTM solutions is necessary during reagent development, performance evaluation, and clinical application.

12.
Clin Infect Dis ; 72(12): 2203-2205, 2021 06 15.
Article in English | MEDLINE | ID: covidwho-1269541

ABSTRACT

Seventy-six days after the coronavirus disease 2019 epidemic was contained in Wuhan, the Chinese government carried out a citywide severe acute respiratory syndrome coronavirus 2 nucleic acid testing initiative for all residents from 14 May to 1 June 2020. Our hospital tested 107 662 residents around Huanan seafood market, uncovering a positivity rate of 0.006%.


Subject(s)
COVID-19 , SARS-CoV-2 , China/epidemiology , Humans , Seafood
13.
Lancet ; 397(10279): 1075-1084, 2021 03 20.
Article in English | MEDLINE | ID: covidwho-1142326

ABSTRACT

BACKGROUND: Wuhan was the epicentre of the COVID-19 outbreak in China. We aimed to determine the seroprevalence and kinetics of anti-SARS-CoV-2 antibodies at population level in Wuhan to inform the development of vaccination strategies. METHODS: In this longitudinal cross-sectional study, we used a multistage, population-stratified, cluster random sampling method to systematically select 100 communities from the 13 districts of Wuhan. Households were systematically selected from each community and all family members were invited to community health-care centres to participate. Eligible individuals were those who had lived in Wuhan for at least 14 days since Dec 1, 2019. All eligible participants who consented to participate completed a standardised electronic questionnaire of demographic and clinical questions and self-reported any symptoms associated with COVID-19 or previous diagnosis of COVID-19. A venous blood sample was taken for immunological testing on April 14-15, 2020. Blood samples were tested for the presence of pan-immunoglobulins, IgM, IgA, and IgG antibodies against SARS-CoV-2 nucleocapsid protein and neutralising antibodies were assessed. We did two successive follow-ups between June 11 and June 13, and between Oct 9 and Dec 5, 2020, at which blood samples were taken. FINDINGS: Of 4600 households randomly selected, 3599 families (78·2%) with 9702 individuals attended the baseline visit. 9542 individuals from 3556 families had sufficient samples for analyses. 532 (5·6%) of 9542 participants were positive for pan-immunoglobulins against SARS-CoV-2, with a baseline adjusted seroprevalence of 6·92% (95% CI 6·41-7·43) in the population. 437 (82·1%) of 532 participants who were positive for pan-immunoglobulins were asymptomatic. 69 (13·0%) of 532 individuals were positive for IgM antibodies, 84 (15·8%) were positive for IgA antibodies, 532 (100%) were positive for IgG antibodies, and 212 (39·8%) were positive for neutralising antibodies at baseline. The proportion of individuals who were positive for pan-immunoglobulins who had neutralising antibodies in April remained stable for the two follow-up visits (162 [44·6%] of 363 in June, 2020, and 187 [41·2%] of 454 in October-December, 2020). On the basis of data from 335 individuals who attended all three follow-up visits and who were positive for pan-immunoglobulins, neutralising antibody levels did not significantly decrease over the study period (median 1/5·6 [IQR 1/2·0 to 1/14·0] at baseline vs 1/5·6 [1/4·0 to 1/11·2] at first follow-up [p=1·0] and 1/6·3 [1/2·0 to 1/12·6] at second follow-up [p=0·29]). However, neutralising antibody titres were lower in asymptomatic individuals than in confirmed cases and symptomatic individuals. Although titres of IgG decreased over time, the proportion of individuals who had IgG antibodies did not decrease substantially (from 30 [100%] of 30 at baseline to 26 [89·7%] of 29 at second follow-up among confirmed cases, 65 [100%] of 65 at baseline to 58 [92·1%] of 63 at second follow-up among symptomatic individuals, and 437 [100%] of 437 at baseline to 329 [90·9%] of 362 at second follow-up among asymptomatic individuals). INTERPRETATION: 6·92% of a cross-sectional sample of the population of Wuhan developed antibodies against SARS-CoV-2, with 39·8% of this population seroconverting to have neutralising antibodies. Our durability data on humoral responses indicate that mass vaccination is needed to effect herd protection to prevent the resurgence of the epidemic. FUNDING: Chinese Academy of Medical Sciences & Peking Union Medical College, National Natural Science Foundation, and Chinese Ministry of Science and Technology. TRANSLATION: For the Chinese translation of the abstract see Supplementary Materials section.


Subject(s)
Antibodies, Neutralizing/blood , Antibodies, Viral/blood , COVID-19/immunology , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/blood , COVID-19/epidemiology , COVID-19/prevention & control , Child , Child, Preschool , China/epidemiology , Coronavirus Nucleocapsid Proteins/immunology , Cross-Sectional Studies , Female , Follow-Up Studies , Humans , Immunity, Herd/immunology , Immunity, Humoral , Infant , Infant, Newborn , Longitudinal Studies , Male , Mass Vaccination/organization & administration , Middle Aged , Seroepidemiologic Studies , Young Adult
14.
Journal of Third Military Medical University ; 42(15):1483-1488, 2020.
Article in Chinese | GIM | ID: covidwho-890799

ABSTRACT

Objective: To investigate and analyze the incidence rate, clinical features and risk factors of lower extremity thrombosis in patients with coronavirus disease 2019 (COVID-19).

15.
Clin Microbiol Infect ; 26(12): 1670-1675, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-846867

ABSTRACT

OBJECTIVES: To describe the fraction of asymptomatic health-care workers (HCWs) in two designated hospitals for coronavirus disease 2019 (COVID-19) treatment in Wuhan and explore the factors associated with asymptomatic severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: All HCWs in Wuhan Union Hospital and Wuhan Red Cross Hospital with either positive SARS-CoV-2 nucleic acid or positive antibody test before 18 April 2020 were included. Exposure, epidemiological and demographic information were retrospectively collected by a structured questionnaire. Medical records were also reviewed for clinical characteristics and CT images of HCWs. RESULTS: As of 18 April 2020, a total of 424 HCWs were identified. Among them, 276 (65.1%) were symptomatic and 148 (34.9%) were asymptomatic. Fifty-five (19.9%) families of the symptomatic HCWs and 16 (10.8%) families of the asymptomatic HCWs were infected with SARS-CoV-2. HCWs with infected family members tended to be symptomatic (OR 2.053, 95% CI 1.130-3.730; p 0.018). Multivariable logistic regression analysis exhibited that performing tracheal intubation or extubation (OR 4.057, 95% CI 1.183-13.909; p 0.026) was associated with an increased likelihood of symptomatic SARS-CoV-2 infection, whereas consistent use of N95 respirators (OR 0.369, 95% CI 0.201-0.680; p 0.001) and eye protection (OR 0.217, 95% CI 0.116-0.404; p < 0.001) were associated with an increased likelihood of asymptomatic SARS-CoV-2 infection. CONCLUSIONS: Asymptomatic SARS-CoV-2 infection in HCWs comprised a considerable proportion of HCW infections during the pandemic of COVID-19. Those who performed tracheal intubation or extubation were most likely to develop related symptoms, whereas those taking aggressive measures, including consistent use of N95 masks and eye protection, tended to be asymptomatic cases.


Subject(s)
Asymptomatic Infections/epidemiology , COVID-19/epidemiology , Health Personnel/statistics & numerical data , Infectious Disease Transmission, Patient-to-Professional/statistics & numerical data , Adult , China/epidemiology , Female , Hand Hygiene/statistics & numerical data , Hospitals/statistics & numerical data , Humans , Infectious Disease Transmission, Patient-to-Professional/prevention & control , Intubation, Intratracheal/adverse effects , Male , Middle Aged , N95 Respirators/statistics & numerical data , Personal Protective Equipment/statistics & numerical data , Retrospective Studies , Surveys and Questionnaires
16.
Innovation (N Y) ; 1(2): 100022, 2020 Aug 28.
Article in English | MEDLINE | ID: covidwho-692819

ABSTRACT

An increasing number of patients are being killed by coronavirus disease 2019 (COVID-19), however, risk factors for the fatality of COVID-19 remain unclear. A total of 21,392 COVID-19 cases were recruited in the Hubei Province of China between December 2019 and February 2020, and followed up until March 18, 2020. We adopted Cox regression models to investigate the risk factors for case fatality and predicted the death probability under specific combinations of key predictors. Among the 21,392 patients, 1,020 (4.77%) died of COVID-19. Multivariable analyses showed that factors, including age (≥60 versus <45 years, hazard ratio [HR] = 7.32; 95% confidence interval [CI], 5.42, 9.89), sex (male versus female, HR = 1.31; 95% CI, 1.15, 1.50), severity of the disease (critical versus mild, HR = 39.98; 95% CI, 29.52, 48.86), comorbidity (HR = 1.40; 95% CI, 1.23, 1.60), highest body temperature (>39°C versus <39°C, HR = 1.28; 95% CI, 1.09, 1.49), white blood cell counts (>10 × 109/L versus (4-10) × 109/L, HR = 1.69; 95% CI, 1.35, 2.13), and lymphocyte counts (<0.8 × 109/L versus (0.8-4) × 109/L, HR = 1.26; 95% CI, 1.06, 1.50) were significantly associated with case fatality of COVID-19 patients. Individuals of an older age, who were male, with comorbidities, and had a critical illness had the highest death probability, with 21%, 36%, 46%, and 54% within 1-4 weeks after the symptom onset. Risk factors, including demographic characteristics, clinical symptoms, and laboratory factors were confirmed to be important determinants of fatality of COVID-19. Our predictive model can provide scientific evidence for a more rational, evidence-driven allocation of scarce medical resources to reduce the fatality of COVID-19.

17.
Biosaf Health ; 2(4): 232-237, 2020 Dec.
Article in English | MEDLINE | ID: covidwho-664504

ABSTRACT

The outbreak of coronavirus disease 2019 (COVID-19) in Wuhan, China, was caused by a novel coronavirus (CoV), named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The rapid detection of viral nucleic acids is critical for the early identification of infected cases. We have developed two TaqMan real-time reverse transcription-PCR assays to detect SARS-CoV-2. The designed primers target the nucleocapsid (N) and open reading frame (ORF) 1b gene regions, where the probes discriminate SARS-CoV-2 from other human and animal CoVs. The sensitivities are one genomic copy per reaction for the N gene assay and ten copies for the ORF 1b gene assay. The overall linear detection ranges are 1-106 and 10-106 copies per reaction for the N gene assay and the ORF 1b gene assay, respectively. Surveillance of 23 suspected COVID-19 patients demonstrated that SARS-CoV-2 could be detected from 100% (23/23) and 62.5% (16/23) of clinical specimens by the N gene assay and the ORF 1b gene assay, respectively. All of the samples not detected by the ORF 1b gene assay were throat swabs, indicating a lower viral load in the upper respiratory tract and the relatively lower sensitivity of the ORF 1b gene assay. The assays developed in the present study offer alternative diagnostic tests for COVID-19.

19.
Nature ; 583(7818): 830-833, 2020 07.
Article in English | MEDLINE | ID: covidwho-220333

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19), which has become a public health emergency of international concern1. Angiotensin-converting enzyme 2 (ACE2) is the cell-entry receptor for severe acute respiratory syndrome coronavirus (SARS-CoV)2. Here we infected transgenic mice that express human ACE2 (hereafter, hACE2 mice) with SARS-CoV-2 and studied the pathogenicity of the virus. We observed weight loss as well as virus replication in the lungs of hACE2 mice infected with SARS-CoV-2. The typical histopathology was interstitial pneumonia with infiltration of considerable numbers of macrophages and lymphocytes into the alveolar interstitium, and the accumulation of macrophages in alveolar cavities. We observed viral antigens in bronchial epithelial cells, macrophages and alveolar epithelia. These phenomena were not found in wild-type mice infected with SARS-CoV-2. Notably, we have confirmed the pathogenicity of SARS-CoV-2 in hACE2 mice. This mouse model of SARS-CoV-2 infection will be valuable for evaluating antiviral therapeutic agents and vaccines, as well as understanding the pathogenesis of COVID-19.


Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/pathology , Coronavirus Infections/virology , Lung/pathology , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Transgenes , Angiotensin-Converting Enzyme 2 , Animals , Antigens, Viral/immunology , Antigens, Viral/metabolism , Betacoronavirus/immunology , Betacoronavirus/metabolism , Bronchi/pathology , Bronchi/virology , COVID-19 , Coronavirus Infections/immunology , Disease Models, Animal , Epithelial Cells/pathology , Epithelial Cells/virology , Female , Humans , Immunoglobulin G/immunology , Lung/immunology , Lung/virology , Lymphocytes/immunology , Macrophages, Alveolar/immunology , Macrophages, Alveolar/virology , Male , Mice , Mice, Transgenic , Pandemics , Pneumonia, Viral/immunology , Receptors, Complement 3d/genetics , Receptors, Complement 3d/metabolism , SARS-CoV-2 , Virus Replication , Weight Loss
SELECTION OF CITATIONS
SEARCH DETAIL