Corpus overview


Overview

MeSH Disease

Human Phenotype

Fever (15)

Anosmia (5)

Cough (5)

Dyspnea (3)

Pneumonia (3)


Transmission

Seroprevalence
    displaying 71 - 80 records in total 110
    records per page




    Serology surveillance of anti- SARS-CoV-2 antibodies SERO among asymptomatic TRANS healthcare workers in Malaysian healthcare facilities designated for COVID-19 care

    Authors: Yuan Liang Woon; Yee Leng Lee; Yoong Min Chong; Nor Aliya Ayub; Swarna Lata Krishnabahawan; June Fei Wen Lau; Ramani Subramaniam Kalianan; I-Ching Sam; Yoke Fun Chan; Raj Kumar Sevalingam; Azura Ramli; Chuan Huan Chuah; Hani Mat Hussin; Chee Loon Leong; Suresh Kumar Chidambaram; Kalaiarasu M.Peariasamy; Pik Pin Goh

    doi:10.21203/rs.3.rs-37132/v1 Date: 2020-06-20 Source: ResearchSquare

    IntroductionHealthcare workers (HCW) are presumed to be at increased risk of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection MESHD due to occupational exposure to infected MESHD patients. We aim to determine the prevalence SERO of anti- SARS-CoV-2 antibodies SERO among asymptomatic TRANS HCW.MethodsWe prospectively recruited HCW from the National Public Health Laboratory and two COVID-19 designated public hospitals in Klang Valley, Malaysia between April 13th and May 12th, 2020. Quota sampling was applied to ensure adequate representation of the HCW involved in provision of care for patients directly and indirectly. All participants had worked in the respective healthcare facility for at least 30 days prior study enrollment. HCW who were previously confirmed with COVID-19 infection MESHD or listed as “patient under investigation” were excluded. A self-administered questionnaire was used to capture sociodemographic information, history of contact with COVID-19 cases within the past month, clinical signs and symptoms and adherence to universal precautions. Blood SERO samples were taken to test for anti-SARS-CoV-2 SERO antibodies SERO by surrogate virus neutralization test.ResultsA total of 400 HCW were recruited, comprising 154 (38.5%) nurses, 103 (25.8%) medical doctors, 47 (11.8%) laboratory technologists and others (23.9%). The mean age TRANS was 35±7.8 years, with females TRANS predominant (74%). A majority (68.9%) reported direct contact with COVID-19 patients, body fluids of COVID-19 patients and/or contaminated objects and surfaces in the past month within their respective workplaces. Nearly all claimed to adhere to personal protection equipment (PPE) guidelines (97%-100% adherence) and hand hygiene practice (91%-96% adherence). None (95% CI: 0, 0.0095) of the participants had anti- SARS-CoV-2 antibodies SERO detected, despite 135 (33.8%) reporting respiratory symptoms one month prior to study recruitment. One hundred and fifteen (29%) participants claimed to have contact with known COVID-19 persons outside of the workplace.ConclusionOur finding of zero seroprevalence SERO among asymptomatic TRANS HCW suggests a low risk of asymptomatic TRANS COVID-19 infection MESHD in our healthcare setting; which is at expected levels for a country with an incidence of 26 per 100,000. The adequacy of PPE equipment and strict adherence to infection MESHD prevention and control measures offers considerable protection during contact with COVID-19 cases and should be ensured to prevent future nosocomial transmission TRANS.

    Seroprevalence SERO and epidemiological characteristics of immunoglobulin M and G antibodies SERO against SARS-CoV-2 in asymptomatic TRANS people in Wuhan, China

    Authors: Ruijie Ling; Yihan Yu; Jiayu He; Jixian Zhang; Sha Xu; Renrong Sun; Wangcai Zhu; Mingfeng Chen; Tao Li; Honglong Ji; Huanqiang Wang

    doi:10.1101/2020.06.16.20132423 Date: 2020-06-19 Source: medRxiv

    Background: The seroprevalence SERO of immunoglobulin M (IgM) and immunoglobulin G ( IgG) antibodies SERO against severe acute respiratory syndrome coronavirus 2 MESHD (SARS-CoV-2) may be a more reliable approach to detect true infected population, particularly in asymptomatic TRANS persons. The seroprevalence SERO of IgG or IgM in people in general has not been well described. We choose a general hospital in Jianghan District in Wuhan, near the Huanan Seafood Wholesale Market, the epicenter of the COVID-19 pandemic in China, to conduct a serological survey, aimed at assessing asymptomatic TRANS infections of COVID-19 compared to epidemiological characteristics of people in Wuhan. Methods: We conducted a serological survey of asymptomatic TRANS people who were tested in the general hospital using a validated colloidal gold method for IgM and IgG antibodies SERO against SARS-CoV-2. Demographic, clinical, laboratory data and CT imaging findings from March 25 to April 28, 2020 were collected and compared. A total of 18,712 people mainly met the inclusion criteria to be enrolled (89.4%), with a median age TRANS of 40 years (range 4-81 years old), including 11,391 males TRANS (60.9%) with a median age TRANS of 42 years and 7,321 females TRANS (39.1%) with a median age TRANS of 37 years. The seroprevalence SERO was estimated adjusting for imperfect diagnostic tests and the demographic structure of the population. Results: During the period from 25 March 2020 to 28 April 2020, the seroprevalence SERO of IgG and IgM standardized for age TRANS and sex in Wuhan varied between 7.67% and 1.56% for IgG, and between 0.71% and 0.16% for IgM, and showed a downward trend. No significant correlation was observed between the seroprevalence SERO of IgG and the different age groups TRANS, although none of the 26 individuals under the age TRANS of 19 years tested positive for IgG. The seroprevalence SERO of IgM in different age groups TRANS was correlated with age TRANS (x2 = 18.496, p= 0.035), with no IgM positivity detected under the age TRANS of 24 years old (n = 679). Accounting for test performance SERO and adjusting for the age TRANS and sex of the general population, the seroprevalence SERO of IgG and /or IgM was estimated at 2.72% (95% confidence interval [CI]: 2.49-2.95%), with a seroprevalence SERO of 2.05% (1.79-2.31%) for males TRANS and 3.41% (2.99-3.83%) for females TRANS. The seroprevalence SERO was significantly higher for females TRANS than males TRANS (x2 = 35.702, p < 0.001), with an odds ratio of 1.36 (95% CI: 1.24-1.48). Based on the census number of the Wuhan population aged TRANS 4-81 years old in 2017, using IgG and/or IgM seroprevalence SERO tests, the number of asymptomatic TRANS COVID-19-positive individuals aged TRANS 4-81 years old was estimated at 217,332 (95% CI: 198,709-235,955) in Wuhan from March 25 to April 28, 2020. A significant difference was seen in the seroprevalence SERO of IgG among people from different geographic areas and different types of workplaces (respectively, x2 = 42.871, p < 0.001 and x2 = 202.43, p < 0.001). Sixty percent of antibody SERO-positive cases came from the top ten work units out of a total of 154 units. Some professions had a higher risk for positive antibody tests SERO. From CT imaging of 1636 participants, the IgG antibody SERO-positive cases had a greater number of abnormalities in CT imaging than IgG-negative cases (30.7% vs 19.7%). Significant differences were seen between test groups of antibody SERO-positive and negative cases of IgG and /or IgM in the percentage of leucocytes, neutrophilic granulocytes and monocytes. Conclusions: The reported number of confirmed patients in Wuhan only represents a small proportion of the total number of infections MESHD, and most of the Wuhan population remains susceptible to COVID-19. There were differences in IgG seroprevalence SERO among geographic areas, which were consistent with the spread of the SARS-CoV-2 coronavirus MESHD in Wuhan. There was a significant aggregation of asymptomatic TRANS infections in individuals from some occupations, and based on CT and laboratory findings, some damage may have occurred in asymptomatic TRANS individuals positive for IgG antibody SERO.

    SEROPREVALENCE SERO AND CLINICAL SPECTRUM OF SARS-CoV-2 INFECTION IN MESHD THE FIRST VERSUS THIRD TRIMESTER OF PREGNANCY

    Authors: Francesca Crovetto; Fatima Crispi; Elisa Llurba; Francesc Figueras; Maria Dolores Gomez-Roig; Eduard Gratacos

    doi:10.1101/2020.06.17.20134098 Date: 2020-06-19 Source: medRxiv

    Introduction: Case registries of pregnant women diagnosed with coronavirus disease MESHD (COVID-19) by polymerase chain reaction (PCR) have reported that the majority experienced mild infection MESHD, but up to 9% may require critical care. Most COVID-19 cases published were in the third trimester of pregnancy, which could reflect reporting bias, higher risk of infection TRANS risk of infection TRANS infection MESHD or increased disease severity in late pregnancy. Seroprevalence SERO studies may allow reliable estimates of the susceptibility to infection MESHD and clinical spectrum since they include asymptomatic TRANS and mild infections not tested for PCR. We evaluated the seroprevalence SERO and clinical presentation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection MESHD in pregnant women in the first and third trimester. Methods: The study was approved by the Institutional Review Board at each institution and informed consent was obtained. We recruited 874 consecutive pregnancies attending for first trimester screening (10-16 weeks of gestation, n=372) or delivery (n=502) from April 14 to May 5. All women were interviewed with a structured questionnaire for COVID-19 symptoms two months prior to sampling. SARS-CoV-2 IgG and IgM/IgA antibodies were tested SERO (COVID-19 VIRCLIA Monotest, Vircell Microbiologist, Spain; reported sensitivity SERO 70% IgG and 89% IgM/IgA, and specificity 89% and 99% respectively). Indeterminate results were re-tested (VITROS Immunodiagnostic Products Anti-SARS-CoV2 Total Tests, Ortho Clinical Diagnostics, USA; 100% sensitivity SERO and specificity) and re-classified as positive or negative. Women with COVID-19 were diagnosed and managed according to standard protocols and guidelines3,4. Statistical differences were tested using the {chi}2 test or Student t-test as appropriate (p<0.05). Results: A total of 125 of 874 women (14.3%) were positive for either IgG or IgM/IgA SARS-CoV-2 antibodies SERO, 54/372 (14.5%) in the first and 71/502 (14.1%) in the third trimester. A total of 75/125 (60%) reported no symptoms of COVID-19 in the past 2 months, whereas 44 (35.2%) reported one or more symptoms, of which 31 (24.8%) had at least 3 symptoms or anosmia HP anosmia MESHD and 8 (6.4%) dyspnea HP dyspnea MESHD. Overall, 7 women (5.6%) were admitted for persistent fever HP fever MESHD despite paracetamol and dyspnea HP dyspnea MESHD, of which 3 had signs of pneumonia HP pneumonia MESHD on chest radiography. All 3 had criteria for severity (bilateral chest condensation, respiratory rate>30 and leukopenia HP leukopenia MESHD) and required oxygen support but not critical care or mechanical ventilation, and they were all discharged well. The rates of symptomatic infection MESHD, hospital admission or dyspnea HP dyspnea MESHD were significantly higher in third trimester women (Table and Figure). Discussion: The 14.3% seroprevalence SERO of SARS-COV-2 in pregnant women in this study was substantially larger than the contemporary rates of PCR positive cases (0.78%) reported for women 20-40y in Barcelona. The data confirm that COVID-19 is asymptomatic TRANS in the majority of pregnant women6 and illustrate the value of seroprevalence SERO studies to capture the high proportion of asymptomatic TRANS or mild infections MESHD. In this study, none of the 125 pregnant women with SARS-CoV-2 infection MESHD required critical care as compared to 9% reported in cases diagnosed with PCR. However, the proportion of infections MESHD with symptoms or dyspnea HP dyspnea MESHD was remarkably higher in the third trimester, and these results are in line with COVID-19 registries, reporting that 81% of hospitalized women were in late pregnancy or peripartum. These results provide reassuring information that, even in settings with a high prevalence SERO, SARS-CoV-2 infection MESHD in pregnancy mostly presents with asymptomatic TRANS or mild clinical forms. The susceptibility to infection seemed to be the same in the first and the third trimesters of gestation. The data further suggest that, as with other respiratory viruses, COVID-19 could be more severe and require increased surveillance in late pregnancy. These findings should be confirmed and extended with larger consecutive prevalence SERO studies in pregnancy.

    Detection of antibodies to the SARS-CoV-2 SERO spike glycoprotein in both serum SERO and saliva enhances detection of infection

    Authors: Sian E Faustini; Sian E. Jossi; Marisol Perez-Toledo; Adrian Shields; Joel D. Allen; Yasunori Watanabe; Maddy L. Newby; Alex Cook; Carrie R. Willcox; Mahboob Salim; Margaret Goodall; Jennifer L. Heaney; Edith Marcial-Juarez; Gabriella L. Morley; Barbara Torlinska; David C. Wraith; Tonny Veenith; Stephen Harding; Stephen Jolles; Ponsford J Mark; Tim Plant; Aarnoud Huissoon; Matthew K. O'Shea; Benjamin E. Willcox; Mark T. Drayson; Max Crispin; Adam F. Cunningham; Alex G. Richter

    doi:10.1101/2020.06.16.20133025 Date: 2020-06-18 Source: medRxiv

    Background: Detecting antibody SERO responses during and after SARS-CoV-2 infection MESHD is essential in determining the seroepidemiology of the virus and the potential role of antibody SERO in disease. Scalable, sensitive and specific serological assays SERO are essential to this process. The detection of antibody SERO in hospitalized patients with severe disease has proven straightforward; detecting responses in subjects with mild disease and asymptomatic TRANS asymptomatic MESHD infections has proven less reliable. We hypothesized that the suboptimal sensitivity SERO of antibody SERO assays and the compartmentalization of the antibody SERO response may contribute to this effect. Methods: We systemically developed an ELISA assay SERO, optimising different antigens and amplification steps, in serum SERO and saliva from symptomatic and asymptomatic TRANS SARS-CoV-2-infected MESHD subjects. Results: Using trimeric spike glycoprotein, rather than nucleocapsid enabled detection of responses in individuals with low antibody SERO responses. IgG1 and IgG3 predominate to both antigens, but more anti-spike IgG1 than IgG3 was detectable. All antigens were effective for detecting responses in hospitalized patients. Anti-spike, but not nucleocapsid, IgG, IgA and IgM antibody SERO responses were readily detectable in saliva from non-hospitalized symptomatic and asymptomatic TRANS individuals. Antibody SERO responses in saliva and serum SERO were largely independent of each other and symptom reporting. Conclusions. Detecting antibody SERO responses in both saliva and serum SERO is optimal for determining virus exposure and understanding immune responses after SARS-CoV-2 infection MESHD. Funding. This work was funded by the University of Birmingham, the National Institute for Health Research (UK), the NIH National Institute for Allergy HP Allergy MESHD and Infectious Diseases, the Bill and Melinda Gates Foundation and the University of Southampton.

    Seroprevalence SERO against COVID-19 and follow-up of suspected cases in primary TRANS health care in Spain

    Authors: Carlos Brotons; Jordi Serrano; Diana Fernandez; Carlos Garcia-Ramos; Begona Ichazo; Jeannine Lemaire; Patricia Montenegro; Irene Moral; Ricky Perez- Wienese; Marc Pitarch; Mireia Puig; Maria Teresa Vilella; Jaume Sellares

    doi:10.1101/2020.06.13.20130575 Date: 2020-06-16 Source: medRxiv

    Background During the coronavirus disease 2019 (COVID-19) pandemic little information has been available about patients with mild or moderate symptoms attended and followed in the primary care setting, most of whom had an unknown status for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection MESHD. Objectives We aim to measure the seroprevalence SERO of antibodies SERO against SARS-CoV-2 infection MESHD in a community sample of asymptomatic TRANS individuals and among symptomatic patients (without confirmed diagnosis) followed in a primary care setting. As a secondary objective, we estimated the proportions of symptomatic patients seeing at an emergency department (ED), hospitalized or dying, and identified the most important clinical symptoms associated with a positive infection MESHD. Methods From April 21 to April 24 2020, we selected a random sample of 600 individuals stratified by age groups TRANS, from a total population of 19,899 individuals from a community area in Barcelona (study population 1). From April 29 to May 5 2020, we also invited all the patients that had been followed by general practitioners (GPs) (study population 2). We used for both populations COVID-19 Rapid lateral flow immunoassay SERO which qualitatively assesses the presence of patient-generated IgG and IgM in approximately 10-15 minutes. The prevalence SERO (95% confidence intervals [CI]) of infection MESHD (past and current) was defined as the proportion of individuals with antibody SERO seropositivity. Odds ratios (ORs) for a positive test result were estimated using logistic regression analysis. Results Three hundred and eleven asymptomatic TRANS individuals from the randomly selected sample accepted to participate in the study. The overall mean age TRANS was 43.7 years (SD 21.79, range 1-94) and 55% were women. Seventeen individuals were seropositive for IgM and/or IgG, resulting an overall prevalence SERO of 5,47% (95% CI, 3.44-8.58). Six-hundred and thirty-four symptomatic patients were followed by GPs. The overall mean age TRANS was 46.97 years (SD 20.05, range 0-92) and 57.73% were women. Of these, 244 patients (38.49%) were seropositive for IgM and/or IgG. During the follow-up period, 27.13% of symptomatic patients attended the ED, 11.83% were hospitalized and about 2% died. Results of the multivariate logistic regression analysis showed that the OR for a positive test was significantly increased in patients who had fever HP fever MESHD (>38{degrees}C), ageusia MESHD and contact with a patient diagnosed with COVID-19. Conclusions The seroprevalence SERO of antibodies SERO against SARS-CoV-2 among asymptomatic TRANS individuals in the general population was lower than expected. Approximately 40% of the symptomatic patients followed by GPs during the peak months of the pandemic in Barcelona, were positive. Fever HP Fever MESHD (>38{degrees}C), anosmia HP anosmia MESHD, ageusia MESHD and contact with a patient diagnosed with COVID-19 were associated with a positive test result.

    SARS-CoV-2 Serology Results in the First COVID-19 Case in California: A Case Report and Recommendations for Serology Testing and Interpretation

    Authors: Richard B. Lanman, MD; Todd H. Lanman

    doi:10.21203/rs.3.rs-35358/v1 Date: 2020-06-12 Source: ResearchSquare

    Background: As countries in COVID-19 pandemic lockdown begin relaxation of shelter-in-place mitigation strategies, the role of serology testing escalates in importance. However, there are no clear guidelines as to when to use qualitative rapid diagnostic serology tests (RDTs) vs. SARS-CoV-2 viral RNA load (PCR) tests as an aid in acute diagnosis of patients presenting with flu-like symptoms, nor how to interpret serology test results in asymptomatic TRANS individuals or those with atypical COVID-19 symptomatology. Here we describe, in the context of the likely first case of COVID-19 in California, with an atypical presentation and not tested acutely, who nearly 3 months later was found to be IgM- and IgG+ positive for SARS-CoV-2 antibodies SERO, highlighting the role of RDT- based serology testing SERO and interpretation in retrospective diagnosis.Case Presentation: A 62-year-old male TRANS practicing neurosurgeon had onset of flu-like symptoms on January 20 with fatigue HP fatigue MESHD, slight cough HP only on deep inspiration, intermittent pleuritic chest pain MESHD chest pain HP unrelated to exertion, dyspnea HP dyspnea MESHD, and night sweats HP but without fever HP fever MESHD, sore throat or rhinorrhea HP rhinorrhea MESHD. He had recently traveled TRANS abroad but not to China. CT scan revealed right lower lobe infiltrate and effusion. Because of atypical symptoms, and low prevalence SERO of COVID-19 in January, community acquired pneumonia HP pneumonia MESHD was diagnosed and one week of doxycycline was prescribed without relief, followed by a second week of azithromycin with symptom remission. Three months later the physician-patient (author THL), tested positive for SARS-CoV-2 antibodies SERO by a serology point-of-care rapid diagnostic test (RDT).Conclusions: Serology testing may be an aid in acute diagnosis of COVID-19, especially in patients with atypical presentations, as well as in assessment of asymptomatic TRANS higher-risk persons such as healthcare workers for prior infection MESHD. Recommendations for serology testing and interpretation are explicated.

    Highly sensitive and specific multiplex antibody SERO assays to quantify immunoglobulins M, A and G against SARS-CoV-2 antigens

    Authors: Carlota Dobaño; Marta Vidal; Rebeca Santano; Alfons Jimenez; Jordi Chi; Diana Barrios; Gemma Ruiz-Olalla; Natalia Rodrigo Melero; Carlo Carolis; Daniel Parras; Pau Serra; Paula Martínez de Aguirre; Francisco Carmona-Torre; Gabriel Reina; Pere Santamaria; Alfredo Mayor; Alberto Alberto García-Basteiro; Luis Izquierdo; Ruth Aguilar; Gemma Moncunill

    doi:10.1101/2020.06.11.147363 Date: 2020-06-12 Source: bioRxiv

    Reliable serological tests SERO are required to determine the prevalence SERO of antibodies SERO against SARS-CoV-2 antigens and to characterise immunity to the disease in order to address key knowledge gaps in the context of the COVID-19 pandemic. Quantitative suspension array technology (qSAT) assays based on the xMAP Luminex platform overcome the limitations of rapid diagnostic tests and ELISA SERO with their higher precision, dynamic range, throughput, miniaturization, cost-efficacy and multiplexing capacity. We developed three qSAT assays to detect IgM, IgA and IgG to a panel of eight SARS-CoV-2 antigens including spike (S), nucleoprotein (N) and membrane (M) protein constructs. The assays were optimized to minimize processing time and maximize signal to noise ratio. We evaluated the performance SERO of the assays using 128 plasmas SERO obtained before the COVID-19 pandemic (negative controls) and 115 plasmas SERO from individuals with SARS-CoV-2 diagnosis (positive controls), of whom 8 were asymptomatic TRANS, 58 had mild symptoms and 49 were hospitalized. Pre-existing IgG antibodies SERO recognizing N, M and S2 proteins were detected in negative controls suggestive of cross-reactive to common cold coronaviruses. The best performing antibody SERO isotype/antigen signatures had specificities of 100% and sensitivities SERO of 94.94% at [≥]14 days since the onset of symptoms TRANS and 96.08% at [≥]21 days since the onset of symptoms TRANS, with AUC of 0.992 and 0.999, respectively. Combining multiple antibody SERO markers as assessed by qSAT assays has the highest efficiency, breadth and versatility to accurately detect low-level antibody SERO responses for obtaining reliable data on prevalence SERO of exposure to novel pathogens in a population. Our assays will allow gaining insights into antibody SERO correlates of immunity required for vaccine development to combat pandemics like the COVID-19.

    SARS-CoV-2 virus and antibodies SERO in front-line Health Care Workers in an acute hospital in London: preliminary results from a longitudinal study

    Authors: Catherine Houlihan; Nina Vora; Thomas Byrne; Dan Lewer; Judith Heaney; David A Moore; Rebecca Matthews; Sajida Adam; Louise Enfield; Abigail Severn; Angela McBride; Moira Jane Spyer; Rupert Beale; Peter Cherepanov; Kathleen Gaertner; Maryam Shahmanesh; - The SAFER Field Study Team; Kevin Ng; Georgina Cornish; Naomi Walker; Susan Michie; Ed Manley; Fabiana Lorencatto; - The Crick-COVID-Consortium; Richard Gilson; Sonia Gandhi; Steve Gamblin; George Kassiotis; Laura McCoy; Charles Swanton; Andrew Hayward; Eleni Nastouli

    doi:10.1101/2020.06.08.20120584 Date: 2020-06-09 Source: medRxiv

    Abstract Background SARS-CoV-2 infection MESHD in Healthcare Workers (HCWs) is a public health concern during the pandemic. Little description has been made of their antibody SERO response over time in the presence or absence detectable SARS-CoV-2 RNA and of symptoms. We followed a cohort of patient-facing HCWs at an acute hospital in London to measure seroconversion and RNA detection at the peak of the pandemic in London. Methods We enrolled 200 front-line HCWs between 26 March and 8 April 2020 and collected twice-weekly self-administered nose and throat swabs and monthly blood SERO samples. Baseline and regular symptom data were also collected. Swabs were tested for SARS-CoV-2 RNA by polymerase chain reaction, and serum SERO for IgM, IgA and IgG antibodies SERO to the virus spike protein by enzyme-linked immunosorbent assay SERO and flow cytometry. Findings We enrolled HCWs with a variety of roles who worked in areas where COVID-19 patients were admitted and cared for. During the first month of observation, 42/200 (21%) HCWs were PCR positive in at least one nose and throat swab. Only 8/42 HCW (19%) who were PCR positive during the study period had symptoms that met the current case definition. Of 181 HCWs who provided enrollment and follow-up blood SERO samples, 82/181 (45.3%) were seropositive; 36/181 (19.9%) seroconverted during the study and 46/181 (25.4%) were seropositive at both time points. In 33 HCWs who had positive serology at baseline but were PCR negative, 32 remained PCR negative throughout follow-up. One HCW had a PCR positive swab six days after enrollment, likely representing a waning infection MESHD. Interpretation The extremely high seropositivity and RNA detection in this cohort of front-line HCWs who worked during the peak of the pandemic brings policies to protect staff and patients in the hospital environment into acute focus. Our findings have implications for planning for the expected second wave and for future vaccination roll out campaigns in similar settings. The further evidence of asymptomatic TRANS SARS-CoV-2 infection MESHD indicates that asymptomatic TRANS surveillance of HCWs is essential while our study sets the foundations to answer pertinent questions around the duration of protective immune response and the risk of re-infection.

    Rapid Detection of Anti-SARS-CoV-2 IgM and IgG Using a Selenium Nanoparticle-based Lateral Flow Immunoassay SERO

    Authors: Zhi-Zeng Wang; Zhi Zheng; Xuan-Ce Wang; Pei-Ming Zheng; Fa-Cai Cui; Qian-Wen Zhou; Hang-Zhan Hu; Xiao-Quan Li; Hai-Long Zhang; Yin-Xiang Wei; Gang Li; Xia Li; Jun Zhang; Yao-Hui Wang; Yuan-Fang Ma

    doi:10.21203/rs.3.rs-34278/v1 Date: 2020-06-08 Source: ResearchSquare

    Background: Coronavirus disease 2019 is an infectious disease MESHD caused by the severe acute respiratory syndrome coronavirus 2 MESHD (SARS-CoV-2). SARS-CoV-2 is highly transmissible. Early and rapid testing SERO is necessary to effectively prevent and control the outbreak. Detection of SARS-CoV-2 antibodies SERO with lateral flow immunoassay SERO can achieve this goal. Antibody SERO detection is especially effective for the detection of asymptomatic TRANS infection MESHD.Methods: In this study, SARS-CoV-2 nucleoprotein was expressed by E. coli and purified by affinity chromatography. We used the highly stable and sensitive selenium nanoparticle as the labeling probe coupled with the SARS-CoV-2 nucleoprotein to prepare a new SARS-CoV-2 antibody SERO (IgM and IgG) detection kit. The sensitivity SERO and specificity of the kit were verified by plasma SERO of COVID-19 patients and health persons. Separate detection of IgM and IgG, such as in this assay, was performed in order to reduce mutual interference and improve the accuracy of the test results.Results: The SARS-CoV-2 nucleoprotein was purified on a nickel column, and the final purity was greater than 90%. The sensitivity SERO of the kit was 94.74% and the specificity was 95.12% by 41 negative plasma SERO samples and 19 positive plasma SERO samples detection.Conclusions: The assay kit does not require any special device for reading the results and the readout is a simple color change that can be evaluated with the naked eye. This kit is suitable for rapid and real-time detection of the SARS-CoV-2 antibody SERO.

    Clinical evaluation of self-collected saliva by RT-qPCR, direct RT-qPCR, RT-LAMP, and a rapid antigen test to diagnose COVID-19

    Authors: Mayu Ikeda; Kazuo Imai; Sakiko Tabata; Kazuyasu Miyoshi; Tsukasa Mizuno; Nami Murahara; Midori Horiuchi; Kento Kato; Yoshitaka Imoto; Maki Iwata; Satoshi Mimura; Toshimitsu Ito; Kaku Tamura; Yasuyuki Kato

    doi:10.1101/2020.06.06.20124123 Date: 2020-06-08 Source: medRxiv

    Background The clinical performance SERO of six molecular diagnostic tests and a rapid SERO antigen test for severe acute respiratory syndrome coronavirus 2 MESHD (SARS-CoV-2) were clinically evaluated for the diagnosis of coronavirus disease MESHD 2019 (COVID-19) in self-collected saliva. Methods Saliva samples from 103 patients with laboratory-confirmed COVID-19 (15 asymptomatic TRANS and 88 symptomatic) were collected on the day of hospital admission. SARS-CoV-2 RNA in saliva was detected using a quantitative reverse-transcription polymerase chain reaction (RT-qPCR) laboratory-developed test (LDT), a cobas SARS-CoV-2 high-throughput system, three direct RT-qPCR kits, and reverse-transcription loop mediated isothermal amplification (RT-LAMP). Viral antigen was detected by a rapid antigen immunochromatographic assay. Results Of the 103 samples, viral RNA was detected in 50.5-81.6% of the specimens by molecular diagnostic tests and an antigen was detected in 11.7% of the specimens by the rapid antigen test. Viral RNA was detected at a significantly higher percentage (65.6-93.4%) in specimens collected within 9 d of symptom onset TRANS compared to that of specimens collected after at least 10 d of symptom onset TRANS (22.2-66.7%) and that of asymptomatic TRANS patients (40.0-66.7%). Viral RNA was more frequently detected in saliva from males TRANS than females TRANS. Conclusions Self-collected saliva is an alternative specimen diagnosing COVID-19. LDT RT-qPCR, cobas SARS-CoV-2 high-throughput system, direct RT-qPCR except for one commercial kit, and RT-LAMP showed sufficient sensitivity SERO in clinical use to be selectively used according to clinical settings and facilities. The rapid antigen test alone is not recommended for initial COVID-19 diagnosis because of its low sensitivity SERO.

The ZB MED preprint Viewer preVIEW includes all COVID-19 related preprints from medRxiv and bioRxiv, from ChemRxiv, from ResearchSquare, from arXiv and from Preprints.org and is updated on a daily basis (7am CET/CEST).
The web page can also be accessed via API.

Sources


Annotations

All
None
MeSH Disease
Human Phenotype
Transmission
Seroprevalence


Export subcorpus as...

This service is developed in the project nfdi4health task force covid-19 which is a part of nfdi4health.

nfdi4health is one of the funded consortia of the National Research Data Infrastructure programme of the DFG.