anti-sars-cov-2 rapid test

MD+DI Online is part of the Informa Markets Division of Informa PLCThis site is operated by a business or businesses owned by Informa PLC and all copyright resides with them. Informa PLC's registered office is 5 Howick Place diagnosis of malaria manufacturers , London SW1P 1WG. Registered in England and Wales. Number 8860726. | Aug 04, 2020Researchers have developed a rapid test for the determination of neutralizing antibodies against Sars-Cov-2.The test was developed at the Institute of Virology and Immunology (IVI) of the University of Bern and the Swiss Federal Office for Food Safety and Animal Health, and evaluated in cooperation with colleagues from the Ruhr-Universitt Bochum (RUB) using serum samples from Covid-19 patients.The research was published in the journal onJuly 15, 2020.In order to detect antibodies against Sars-Cov-2 anti-sars-cov-2 rapid test, the researchers used another virus that doesn't propagate. They exchanged the envelope protein of this virus for the spike protein of the novel coronavirus, which mediates virus entry and infection. "As a result anti-sars-cov-2 rapid test, the viruses can be identified by antibodies against Sars-Cov-2," lead author Toni-Luise Meister from the Department of Molecular and Medical Virology at Ruhr-Universitt Bochum, said in a release. "The antibodies bind to the viruses that have been altered in this way and neutralize them so that no longer can penetrate the host cells."In order to check the reliability and comparability with the conventional neutralization test, the researchers applied it to blood samples from Covid-19 patients.Compared to 56 hours for the conventional test, the new test is much faster, with only 18 hours to the test result.Follow us:Images By Tang Ming Tung / Getty Images Recently, Omicron subvariants like EG.5, FL.1.5.1, and the highly-mutated BA.2.86 have been causing alarm and accounting for an increasing number of COVID-19 infections. Although they have many different mutations from known variants, experts say would have no problem detecting them. Heres what you need to know. , chair of the division of infectious diseases at Virginia Commonwealth University Health, told Verywell that the COVID-19 rapid tests are no more or no less effective with the current strains. Most rapid tests are antigen tests, which work by detecting proteins on the surface of the SARS-CoV-2 virus separate from the spike protein involved in viral mutations. These surface proteins have not sufficiently mutated to the point of being undetectable, London SW1P 1WG. Registered in England and Wales. Number 8860726. | Aug 04 wholesale best pregnancy test anti-sars-cov-2 rapid test, he added. According to a risk assessment summary from the Centers for Disease Control and Prevention (CDC), existing tests used to detect COVID-19 remain effective with BA.2.86, which has over 35 amino acid mutations compared to XBB.1.5. The agency says that the anticipated impact of the variant on molecular (including PCR) and antigen-based testing is low. Polymerase chain reaction (PCR) testing is the gold standard for diagnosing COVID-19. , director of the division of infectious diseases and international medicine at the University of Minnesota anti-sars-cov-2 rapid test, told Verywell that several factors can affect how well COVID-19 rapid tests detect new variants. The sampling process, amount of virus present, test sensitivity and expiration, and any major mutations that cause large changes in the virus proteins or antigens should all be considered, she added. If you perform a nasal swab incorrectly, the test might not be able to accurately detect whether you have COVID-19 or not. In addition, rapid tests generally have low detection sensitivity for low viral load samples, which might miss presymptomatic and asymptomatic cases of COVID-19 during the incubation phase. Its necessary to store test kits based on the temperature and storage recommendations indicated by the manufacturer. Keeping tests in the back of a hot car or inside the refrigerator may affect the accuracy of the test. Expired tests may not provide accurate results either. You can tell if a rapid test is expired by checking the box for the expiration date. Some tests do have shelf life extensions granted by the Food and Drug Administration (FDA), meaning they last longer than indicated on the packaging. For instance, the and tests were granted 15- to 22-month and 21- to 24-month shelf life extensions, respectively, earlier this year. You can visit the FDA to check the list of manufacturers and specific lot numbers that were granted the shelf life extensions. Its not yet certain whether current rapid tests for COVID-19 will need tweaking to detect newer variants more effectively, Kline said. Test manufacturers, government agencies anti-sars-cov-2 rapid test, and researchers need to run tests to further verify the sensitivity of the rapid antigen tests in patients with the newer strains of the virus infection, 2020Researchers have developed a rapid test for the determination of neutralizing antibodies against Sars-Cov-2.The test was developed at the Institute of Virology and Immunology (IVI) of the University of Bern and the Swiss Federal Office for Food Safety and Animal Health best mp card test price anti-sars-cov-2 rapid test, Bearman said. The FDA continues to evaluate the impact of SARS-CoV-2 viral mutations on COVID-19 diagnostic tests and will update their guidance when new information becomes available. Just like before, if you get a negative test result, take another test after 48 hours to ensure that it was not a false negative. Experts say COVID-19 rapid tests can still detect the newer SARS-CoV-2 variants that are circulating today. Make sure that you store your test properly, check the expiration date, and use the test correctly to ensure accurate results. Centers for Disease Control and Prevention. .Centers for Disease Control and Prevention. .Wan Z, Zhao Y, Lu R, et al. . . 2021;93(12):6462-6464. doi:10.1002/jmv.27236Food and Drug Administration. . Carla M. Delgado is a health and culture writer based in the Philippines. Thank you, {{form.email}} anti-sars-cov-2 rapid test, for signing up.There was an error. Please try again.By clicking Accept All Cookies, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts. For technical reasons, the English full text will be published approximately two weeks after the German print edition has been published.Reinhardtstr. 34 10117 Berlin Telefon: +49 (0) 30 246267 - 0 Telefax: +49 (0) 30 246267 - 20 E-Mail: entwickelt von Sie finden uns auch auf:RSS-Feed abonnieren:The aim of the collaboration between TalTech and is foremost to develop clinical and point-of-care rapid tests for the detection of SARS-CoV-2. The rapid test using a new method of detection of the virus is meant primarily for family doctors, not for use by patients themselves.In addition to the presence of coronavirus, the rapid test allows to determine its concentration.The new approach is based on the molecular imprinting technology developed at the Laboratory of Biofunctional Materials at TalTech. With said technology, synthetic receptors are created in the structure of a polymer which, when encountering virus particles anti-sars-cov-2 rapid test, for instance, and evaluated in cooperation with colleagues from the Ruhr-Universitt Bochum (RUB) using serum samples from Covid-19 patients.The research was published in the journal onJuly 15 syphilis antibody test suppliers , such as virus particles, based on the same principle as biological receptors, but are more stable than the latter in their characteristics and cheaper.The goal of the first phase of the research work is a sensor chip covered with a synthetic receptor selective for the virus protein, which is ready for use. In the next stage of the work a solution has to be developed for the manufacture of sensor chips rapidly and in big amounts. The sensor chips will then be packaged and be ready for analysis of the viral infection. senior research fellow at the Laboratory of Biofunctional Materials at TalTech, said that in their research the team of researchers in collaboration with have compared real-life negative and positive samples and the initial results allow to say that the method works well. Also a prototype has been completed.The researchers of TalTech have applied for a patent in the United States.With the help of an ETAG grant and together with the faculty of natural sciences at TalTech anti-sars-cov-2 rapid test, the group of researchers led by Vitali Soritski is already exploring possibilities for using the method for the analysis of saliva and blood samples.Dublin, Sept. 26, 2023 (GLOBE NEWSWIRE) -- The report has been added to offering.The global market for COVID-19 Testing estimated at US$24.2 Billion in the year 2022, is projected to reach a revised size of US$5.8 Billion by 2030, growing at a CAGR of -16.3% over the analysis period 2022-2030.The global COVID-19 Testing market is poised for growth anti-sars-cov-2 rapid test, with anticipated annual revenue increases projected from 2022 to 2030. This upswing follows a period of steady expansion experienced between 2020 and 2022.Diverse segments, including RT-PCR Assay Kits anti-sars-cov-2 rapid test, Immunoassay Test Strips/Cassettes, Nasopharyngeal Swabs, Oropharyngeal Swabs, Nasal Swabs anti-sars-cov-2 rapid test, and Other Specimen Types, contribute to the market's development.In the report, RT-PCR Assay Kits, one of the segments anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, is expected to exhibit a -17.1% CAGR and achieve a market value of US$3.9 Billion by the conclusion of the analysis period. Similarly, the Immunoassay Test Strips/Cassettes segment is anticipated to witness growth with a -14.4% CAGR over the next eight years.Geographically, pivotal regions like the USA, Canada, Japan anti-sars-cov-2 rapid test, China, Europe, Asia-Pacific, Latin America, the Middle East, and Africa significantly influence the market's dynamics. End-users such as hospitals, diagnostic centers, and other applications are key drivers of market demand. This underscores the vital role of COVID-19 testing in healthcare and diagnostic industries.The U.S. COVID-19 Testing market is estimated at US$5.9 Billion in 2022, while China, the world's second-largest economy, is projected to reach US$56.9 Million by 2030, albeit with a -30.7% CAGR from 2022 to 2030.Noteworthy geographic markets also include Japan and Canada, both anticipated to decline by -15.2% and -14.6%, respectively, during the 2022-2030 period. Germany, within Europe, is forecasted to decline at an approximate -13.9% CAGR.Distinguished healthcare players like Abbott Laboratories, Hologic Inc., and Thermo Fisher Scientific anti-sars-cov-2 rapid test, amongst others, feature in the comprehensive competitor analysis.Types of COVID-19 TestingDifferent Types of Coronavirus TestsPerformance Analysis of COVID-19 TestsRapid Tests Help in Controlling the VirusHow Will COVID-19 Testing Change in 2021Massive Testing to Become a Way of LifeCOVID-19 to Drive Hospital and Diagnostic Lab Revenues in 2021COVID-19 Testing Witnesses Staggering Growth Due to Rising Incidence of Corona VirusTotal Number of COVID-19 Tests Conducted in the Most Impacted Countries: As of September 1st anti-sars-cov-2 rapid test, 2021Total Number of COVID-19 Tests Worldwide in Select Countries: As of September 1st anti-sars-cov-2 rapid test, 2021Molecular Tests (RT-PCR) Occupy a Predominant Share of the COVID-19 Testing MarketSelect Approved COVID-19 Molecular Assay TestsImmunoassays to Witness Fastest GrowthIncreasing Demand for Antibody TestsHow Antibody (Serology) Tests Were Approved and DevelopedSelect COVID-19 Immunoassay KitsList of US FDA Approved Antigen TestsNasopharyngeal/Oropharyngeal Swabs Remain Primary Sample TypeDiagnostic Laboratories Constitute the Largest End-use SegmentRECENT MARKET ACTIVITYRecent LaunchesRising Incidence of Coronavirus Cases Drive the Need for TestingCOVID-19 Most Impacted 18 Countries Worldwide: As on September 1st, 2021Pandemic Gives Rise to Innovative Partnership ModelsBroader Adoption of Reverse-Transcription Polymerase Chain Reaction-based DiagnosticsIncreasing Point-of-Care Molecular TestingAccelerated Development and Faster Adoption of New TechnologiesExpansion of Manufacturing Capacity in Asia and Shift of SupplyPositioning for the FutureSome Innovative Testing Methods for COVID-19:CRISPRBioluminescence TestingLab-on-chip TestingLAMpore KitsCovid-19 NudgeBox Test by DNANudgeHigh Risk of Infection in Geriatric Population Drives COVID-19 Testing MarketExpanding Elderly Population Worldwide: Breakdown of Number of People Aged 65+ Years in Million by Geographic Region for the Years 2019 and 2030Rapid Test Kits Market for COVID-19 to Exhibit Exponential GrowthSelect Approved COVID-19 Rapid TestsPoint-of-Care Tests Witness Rapid GrowthHigh-Speed NanoPCR Technology Developed for Point-of-Care Diagnosis of COVID-19Mass Community Testing Holds the Key for Effective COVID-19 ManagementThe Need for Rapid Mass Testing Pushes for Production of Novel Testing PlatformsCRISPR Emerges as Cutting-Edge Biotechnology in COVID-19 Diagnostic MarketInnovations and ApprovalsPortable PoC Test with a Smartphone ReaderSaliva TestFDA Approves First Molecular Test for Asymptomatic PatientsNew Molecular Test N1-STOP-LAMPLumiraDx SARS-CoV-2 Antigen TestIntegration of Sophisticated Technology to Drive Market GrowthIsothermal Amplification: An Effective Alternative to RT-PCR for COVID-19 TestingIn-home Testing for Covid-19FDA Authorizes Home Collection Option for LabCorp's COVID-19 Diagnostic TestA Rapid Genomics Strategy to Trace CoronavirusThe pioneering of Rapid GenomicsDigital Healthcare Gains Spotlight Amid COVID-19 PandemicDigital Technologies Gaining Adoption Amid COVID-19List of COVID-19 Contact Tracing AppsAmazon Offers FDA-Approved COVID-19 TestAlliance of BMGF and Life Science Companies Pledge to Improve AccessEnsuring the Perfect Mix of COVID-19 TestingTesting Rate & Average Turnaround Time to Results as Key MetricsGrowing Significance of Pooled TestingParticipation of Public & Private SectorAvoiding Supply MismatchRecent LaunchesNew Test Detects SARS-CoV-2 in Less Than Five MinutesNew COVID-19 Test Provides Faster Results and Eliminates False NegativesNew Rapid Lateral Flow Immunoassay DevelopedUniversity of California Develops Rapid, Accurate Testing for SARS-CoV-2 AntibodiesAbbott Plans Shipment of Tens of Millions of At-Home Coronavirus Tests Costing $25 in Early 2021Quidel Gains FDA Approval for Sofia 2 Antigen TestImproving Medicine with Innovation and Technology and Massachusetts Institute of Technology Develop COVID-19 Testing Impact Calculator (U.S.)Nanomix Offers eLab COVID-19 Rapid Antigen TestAbbott Receives FDA Approval for BinaxNowRoche Introduces Elecsys SARS-CoV-2 Antigen testDnaNudge Offers CovidNudge TestOpen-Source Toolkit Helps Developing Countries Meet Demand for COVID-19 Diagnostics3M Joins Hands with MIT's Sikes Lab to Create Rapid & Affordable COVID-19 TestZTA Biotech Announces "Breakthrough" Development with Antibody TestMolecular Diagnostics Firm QuantuMDx Group Set to Scale up Production of Rapid PCR COVID-19 DeviceMologic Granted CE Mark for Rapid Antigen TestFDA Approves Abbott's COVID-19 Antigen TestAptameXTMCOVID-19 Testing - Global Key Competitors Percentage Market Share in 2022 (E)Competitive Market Presence - Strong/Active/Niche/Trivial for Players Worldwide in 2022 (E)Global Market Prospects and OutlookUS and Europe Dominate anti-sars-cov-2 rapid test, Asia-Pacific to Witness Fastest GrowthAdaltis SrlAlfa Scientific Designs anti-sars-cov-2 rapid test, Inc.A*STAR Experimental Therapeutics CentreAITbiotech Pte., Ltd.Altimmune, Inc.ADS Biotec, Inc.Accelerate Diagnostics, Inc.AccuBioTech Co., Ltd.Access Bio, Inc.Abwiz Bio Inc.AB Diagnostic Systems GmbH1drop, Inc.3B BlackBio Biotech India Ltd.Abacus Diagnostica OyAldatu BiosciencesUS Emerges as a Major Market for COVID-19 TestsCovid-19 Test Supply Chain Issues in the USChallenges Associated with COVID-19 TestingImpact of Surveillance Testing on COVID-19 Test Supply ChainCDC Funding for Covid-19 Vaccination & Testing-Related ActivitiesEscalating Cases of COVID-19 Lead to Spurt in Diagnostic Test InnovationsUptake of At-Home Tests Remains ModestFDA Approves 2 Rapid, At-Home Coronavirus TestsSelect Point Of Care Home Tests in the USPharmacies Now Offering Over-The-Counter Same-day COVID TestsHHS Introduces Pilot Program for Cartridge-based Covid-19 Molecular Test KitsOura Develops New Smart Ring to Detect Covid-19 Symptoms at Early Stage (Finland)Issues with Existing Testing OptionsIssues with At-Home and Point-of-Care Rapid TestsDisparate Costs Continue to Plague US Covid-19 TestingWith Spike in COVID-19 Cases Roiling Testing Efforts, NIH Eyes on Rapid Tests to Push CapacityPromising Technologies under RADx ProgramRapid COVID Tests: Important Tool for RecoveryCalifornia University Installs Vending Machines to Dispense COVID-19 Testing Kits to StudentsFDA Assumes Lukewarm Stance to Home Tests despite COVID-19 Testing Lag in USCMS Prioritizes Covid-19 Testing: Announces New Reimbursement RulesCMS Decreases Price for High-Throughput Technology-Based Covid-19 TestingAging Demographics: A Major Driving FactorNIH FundingUS FDA Approved COVID-19 TestsMarket AnalysisNew Cheaper and Faster COVID-19 Rapid Test Kit Obtains ApprovalCanada Approves First Antigen-Based Rapid COVID-19 TestGovernment of Ontario Introduces Covid-19 Screening Tests at Toronto Pearson International AirportNew Federal Rule in Canada for Air Passengers' COVID-19 TestsJapan Moves to Low-Cost PCR TestingRapid Testing Still Costs a BombMedical Clinics EdgeChina's Qingdao Embarks on Ambitious Mission to Test Entire Population of City for COVID-19 in Five DaysPandemic Exposes Deficiencies in the UK Healthcare SystemUK Opens New Vaccine Centers to Expand Asymptomatic Covid-19 TestingMandatory COVID-19 Tests for UK-Bound TravellersMass Testing Program for COVID-19Mass Testing in SchoolsMass Testing in Cities and TownsNew `Mega Labs` to Speed Up COVID-19 Testing in Early 2021India Hastens Strides toward COVID-19 Testing & Significantly Exceeds Testing Criteria Set by WTOIncrease in Daily Tests for COVID-19 in IndiaIndian Researchers Develop Foremost Paper-based Test to Get Handle over COVID-19Researchers in India Successfully Develop Saliva-based Test for COVID-19Home Kits for COVID-19 Testing in IndiaThe Rockefeller Foundation Injects New Grants to Boost Covid-19 Testing & Surveillance in IndiaAuthorities Succeed In Successfully Evading the Virus ImpactWidespread Roll Out of Testing Laboratories Yields ResultsWHO Pushes for Rapid Testing to Boost Africa's Response to COVID-19 PandemicCOVID-19 Testing Benefits from Existing TB and HIV Laboratory SystemsRDTs Arrive in African CountriesFor more information about this report visit ResearchAndMarkets.com is the world's leading source for international market research reports and market data. We provide you with the latest data on international and regional markets anti-sars-cov-2 rapid test, key industries, the top companies, new products and the latest trends. Vietnam has adequate testing techniques to detect and diagnose the SARS-CoV-2 virus, including , , according to Deputy Minister of Health Tran Van Thuan. He made the remark at a teleconference on May 13 with the National Institute of Hygiene and Epidemiology, the Pasteur Institute, and testing establishments of the Ministry of Health (MoH). Thuan said laboratories nationwide are now capable of testing 100,000 single samples per day, and the capacity can increase by five- to ten-fold when it comes to pooled testing. Vietnam has mastered to detect and diagnose the SARS-CoV-2 coronavirus anti-sars-cov-2 rapid test, including the Read time RT-PCR for confirmatory testing, rapid antigen testing, and rapid antibody testing, he went on. Guidelines for each type of testing and different scenarios, including the scenario of 30,000 infected cases recorded in the country, have also been issued anti-sars-cov-2 rapid test, the official noted, asking the General Department of Preventive Medicine and the Administration of Science, Technology and Training to hold regular meetings to share testing experience and expertise with other units and grassroots medical establishments. The communication work will be stepped up to raise public awareness of the importance of testing in the pandemic combat, he said. There are 175 testing labs capable of conducting coronavirus tests nationwide at present anti-sars-cov-2 rapid test, including 125 authorised to carry out confirmatory tests, according to Nguyen Minh Hang, Deputy Director of the General Department of Preventive Medicine. Compared to the previous waves of outbreaks anti-sars-cov-2 rapid test, Vietnams testing capacity has improved very quickly in this fourth wave of COVID-19 infections. Nearly 310,000 samples have been tested since April 27 anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, when the resurgence began, she said. The health ministry said currently there are 16 biological products for RT-PCR test anti-sars-cov-2 rapid test, four for rapid antigen test and nine other for antibody test. All of them have been licensed by the ministry. Besides, Vietnam has used biological products recommended by the World Health Organization or the US Centres for Disease Control and Prevention (CDC). The MoH's Department of Medical Examination Management reported that a total of 100 hospitals nationwide have laboratories that conduct both confirmatory and screening tests. Thuan said the ministry has requested all hospitals with 300 or more beds to set up confirmatory laboratories. He also instructed the department to continue reminding medical facilities to strengthen testing capacity. Health officials at the meeting pointed out that the COVID-19 situation remains complex in many countries, including some sharing the borderlines with Vietnam. Many countries and territories have also recorded the emergence of new coronavirus variants that are more transmissible and dangerous such as the variants first found in the UK and India. As of the noon on May 13 anti-sars-cov-2 rapid test, Vietnam had reported 3 anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test,679 cases of COVID-19 anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, including 2,234 local infections and 1,445 imported ones. A total of 664 cases have been documented since the fourth COVID-19 wave hit Vietnam on April 27. A total of 77 anti-sars-cov-2 rapid test,648 people who came in close contact with patients or arrived from pandemic-hit areas are being quarantined nationwide, including 1,052 at hospitals, 32 anti-sars-cov-2 rapid test,228 at other quarantine sites anti-sars-cov-2 rapid test, and 44,368 at home or accommodations. Among the COVID-19 patients, 19 have tested negative for the coronavirus SARS-CoV-2 once, 18 twice anti-sars-cov-2 rapid test, and 25 thrice. As many as 942,030 frontline medical workers and members of community-based anti-COVID-19 groups in Vietnam had been injected with COVID-19 vaccine as of 4pm on May 12. The country began its COVID-19 inoculation campaign on March 8. To stay safe from COVID-19, people are urged to strictly follow the MoHs 5K health message: khau trang (facemask), khu khuan (disinfection), khoang cach (distance) anti-sars-cov-2 rapid test, khong tu tap (no gathering), and khai bao y te (health declaration)./. Citation numbers are available from Dimensions Patients with chronic inflammatory diseases are often treated with immunosuppressants and therefore are of particular concern during the SARS-CoV-2 pandemic. Serological tests will improve our understanding of the infection and immunity in this population anti-sars-cov-2 rapid test, unless they tests give false positive results. The aim of this study was to evaluate the specificity of SARS-Cov-2 serological assays using samples from patients with chronic inflammatory diseases collected prior to April 2019, thus defined as negative. Samples from patients with multiple sclerosis (MS, n=10) anti-sars-cov-2 rapid test, rheumatoid arthritis (RA, n=47) with or without rheumatoid factor (RF) and/or anti-cyclic citrullinated peptide antibodies (anti-CCP2) and systemic lupus erythematosus (SLE anti-sars-cov-2 rapid test, n=10) with or without RF, were analyzed for SARS-CoV-2 antibodies using 17 commercially available lateral flow assays (LFA), two ELISA kits and one in-house developed IgG multiplex bead-based assay. Six LFA and the in-house validated IgG assay correctly produced negative results for all samples. However, the majority of assays (n=13), gave false positive signal for samples from patients with RA and SLE. This was most notable in samples from RF positive RA patients. No false positive samples were detected in any assay using samples from patients with MS. Poor specificity of commercial serological assays could possibly be, at least partly anti-sars-cov-2 rapid test, due to interfering antibodies in samples from patients with chronic inflammatory diseases. For these patients, the risk of false positivity should be considered when interpreting results of the SARS-CoV-2 serological assays.Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is the causative agent of the coronavirus disease 2019 (COVID-19), which emerged as a pandemic late 2019 (). The cumulative number of infected and fatal cases can be followed at the Johns Hopkins University COVID-19 Dashboard (). Patients with chronic inflammatory disease are often treated with immunomodulatory treatments and therefore potentially more susceptible to infections (). As a result, there has been substantial concern during the pandemic as to the potential increased risk COVID-19 disease severity and mortality among these patient groups (). There is limited evidence about their risk of severe COVID-19, or knowledge of how their disease or immunomodulatory treatment may affect either their pre-existing immunity or ability to develop protective immunity following infection ( anti-sars-cov-2 rapid test, ). Approximately 6% of the worlds population are affected by chronic inflammatory diseases which includes conditions such as multiple sclerosis (MS), rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) (). These are generally progressive diseases and although for the majority there are no cures, treatment is centered around slowing disease progression with immunomodulatory treatments. The hallmarks of autoimmune diseases are inflammation, loss of self-tolerance and the presence of autoantibodies. MS is a chronic inflammatory disorder restricted to the central nervous system, characterized by demyelination, axonal loss and the formation of sclerotic plaques. The worldwide prevalence is estimated to be 2.2 million cases anti-sars-cov-2 rapid test, but with large geographical variation (). RA is a heterogeneous chronic inflammatory disease, which affected close to 5 million people globally by 2010 and with prevalence increasing due to the increased aging of the human population (). The disease is characterized by synovial inflammation and the formation of the pannus, which causes cartilage and bone destruction, joint dysfunction, pain and disability. Rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA), often detected as anti-cyclic citrullinated peptide (CCP) antibodies, are the most frequent and the most studied RA-related autoantibodies. RF is an antibody reactive with the Fc portion of IgG anti-sars-cov-2 rapid test, mainly consisting of IgM in Caucasian RA populations, but also IgG and IgA RF are present. Although RF is detected in approximately 70% of RA patients anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, the presence of RF is not specific for RA. These autoantibodies are also present in a variety of other diseases as well as in the general population and may increase with age, smoking and chronic infection ( anti-sars-cov-2 rapid test, ). SLE is a systemic inflammatory disease of the connective tissue, characterized by a loss of self-tolerance and leading to production and deposition of a large panel of autoantibodies and immune complexes formation (). Clinical manifestation of SLE is heterogeneous and can affect multiple organs. Approximately 25% of SLE patients have RF () anti-sars-cov-2 rapid test, but these patients can also have anti-nuclear antibodies (ANA) and anti- double-stranded (ds) DNA antibodies.Serological tests are useful for determining past infection and present immunity. The presence of IgM antibodies indicates a recent infection, whereas presence of IgG antibodies indicates possible long-lasting immunity (). Important information can be achieved by having access to reliable serological methods during a pandemic; to identify seropositive people for convalescent plasma donations; guide policies and ease restrictions on human mobility based on sero-epidemiological evidence; ensure immunity to allow key workers to return to work after exposure; and evaluate vaccine development studies and vaccine strategies.Due to the substantial global demand, SARS-CoV-2 serological testing has been rapidly developed and released to the market. The assays are validated before release and also often independently verified before being approved (, ). However, the panel of samples used to determine specificity is often focused on ruling out cross-reactivity with other viral infections and might not include serum from patients with chronic inflammatory diseases anti-sars-cov-2 rapid test, even though it is recommended (). Based on experience from development and validation of serology assays for measuring anti-drug antibodies (ADA) in persons with chronic inflammatory disease, it is recommended to show specificity against drug nave patient serum anti-sars-cov-2 rapid test, as antibodies present in patients with autoimmune diseases are known to interact with reagents in serological assays and give unspecific signal (, ). Given the significant role serological tests may have as useful wide-spread screening tools for immunity, it is important to verify the specificity of SARS-CoV-2 serological tests in a similar way for specificity in patient groups with autoimmune diseases, using samples that were collected before the pandemic.The aim of this pilot study was to verify the specificity in a number of the commercially available SARS-CoV-2 serological tests, using a panel of samples from patients with different chronic inflammatory diseases collected before the SARS-CoV-2 outbreak as negative controls, to get an indication of the extent of the issue for further developments, validations and verifications of serology assays.To evaluate specificity of SARS-CoV-2 serological assays in patients with chronic inflammatory diseases anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, a selection of negative control samples was retrieved from the biobank (n=68). To exclude individuals with risk of previous exposure to SARS-CoV-2 infection, only samples collected before April 2019, (1-22 years since time of collection, ) anti-sars-cov-2 rapid test, were included in the study. Serum samples were selected from patients with MS (n=10), RA (n=47), of which 2 samples were from the same patient), or SLE (n=10) (). Patients characteristics.The MS patients were diagnosed according to the 2017 updated McDonald criteria (). The RA diagnoses were determined according to the 1987 revised American College of Rheumatology disease classification criteria by rheumatologists anti-sars-cov-2 rapid test, within 12 months after the first symptoms of joint disease (). For the SLE patients, the diagnoses were determined according to the American College of Rheumatism () and/or The Systemic Lupus Erythematosus Collaborating Clinics ().MS patient samples were collected in a research laboratory providing routine testing for anti-drug antibodies (ADAs) at the Centre for Molecular Medicine, Karolinska Institutet in Stockholm and had been treated with interferon beta (IFN). Three MS samples were ADA positive. Of the RA samples, 40 were from the Swedish population-based case control study Epidemiological Investigation of RA (EIRA) and had not been treated with any disease modifying anti-rheumatic drug (DMARD) (). Of these patients, 20 were RF and anti-CCP2 positive (50%); six were RF negative but anti-CCP2 positive (15%), and 14 were both RF and anti-CCP2 negative (35%) (). The additional seven RA patient samples were retrieved from a prospective study cohort (Sahlgrenska University Hospital anti-sars-cov-2 rapid test, Gothenburg) and were infliximab (IFX) treated. Of these seven patient samples, three were RF and anti-CCP2 positive; two were RF negative but anti-CCP2 positive; one was RF positive but anti-CCP2 negative anti-sars-cov-2 rapid test, and one sample was both RF and anti-CCP2 negative. The SLE samples were obtained from a study investigating the development of ADA against rituximab (RTX) anti-sars-cov-2 rapid test, and therefore all patients were RTX treated. Five of ten samples was anti-rituximab ADA positive (). All of the SLE patients had ANA and four of them anti-dsDNA.This retrospective cohort study was approved by the Ethics Review Authority in Stockholm and Gothenburg (202023/04, dnr 2020-01649 anti-sars-cov-2 rapid test, 2012/1550-31/3, dnr 96-174). Samples and data were collected with informed consent in compliance with the Helsinki Declaration.Analysis IgA anti-sars-cov-2 rapid test, IgG and IgM isotypes of RA samles from the EIRA cohort and SLE samples was performed using the EliA immunoassay on the Phadia 2500 instrument and the cutoff values as stated in the manufacturers instructions (Phadia GmbH, Uppsala, Sweden) (). Serum samples of RA patients treated with IFX were analyzed for IgM RF using laser nephelometry technique.Anti-CCP2 IgG in EIRA was previously determined using the Immunoscan CCPlus ELISA (Euro-Diagnostica anti-sars-cov-2 rapid test, Malm, Sweden), in accordance with the manufacturers instructions.A total of 19 commercially available serological assays were evaluated in this study and compared to an in-house assay. Two Enzyme-Linked Immunosorbent Assays (ELISA) and 17 rapid diagnostic lateral flow assays (LFA) were included. These tests were assigned a letter from A S () and referred to as such in text and figures in this study. The brand name, antigen, manufacturer determined specificity and sensitivity, are outlined in . All tests were performed according to manufacturer instructions and using serum. Description of the SARS-CoV-2 serological assays and the test codes used in this study.LFAs are designed to enable point of care analyses and can generate immediate results with read-outs as bands in small cartridges. These rapid lateral flow tests are developed for whole blood, serum and plasma. At time of testing, the appropriate volume of serum was applied to the designated well and then the buffer was added. After the recommended incubation period, the presence and intensity of the bands were investigated and graded from negative to four levels of positivity by the same operator.The results were compared to an in-house multiplex bead-based and validated SARS-CoV-2 serological assay developed at SciLifeLab and KTH Royal Institute of Technology as previously described (). In brief, IgG reactivity was analyzed in a high-throughput and multiplex bead-based format utilizing 384-well plates and FlexMap3D instrumentations (Luminex Corp) for read-out (). Reactivity against three different in-house produced viral protein variants was used to differentiate between positive and negative samples: Spike trimers comprising the prefusion-stabilized spike glycoprotein ectodomain () (expressed in HEK and purified using a C-terminal Strep II tag) anti-sars-cov-2 rapid test, Spike S1 subunit (expressed in CHO and purified with HPC4 tag) anti-sars-cov-2 rapid test, and the Nucleocapsid protein (expressed in E. coli and purified using an N-terminal His-tag). The antigens were immobilized on magnetic color coded beads (MagPlex anti-sars-cov-2 rapid test, Luminex Corp) and plasma/serum IgG that bound to the antigens were detected by an R-phycoerythrin conjugated goat anti-hIgG (Invitrogen, H10104). Reactivity against at least two out of the three viral antigens included in the panel was required for positive read out. The cut-off for seropositivity was defined as signals above the mean +6 SD of the 12 negative controls included in each assay. The method utilizing the combination of the three antigens has been found to have 99.2% sensitivity (99.6%, 99.2%, 96.7%, respectively, for the three antigens individually) and 99.8% specificity (98.9%, 99.1% anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, 98.4% anti-sars-cov-2 rapid test, respectively, for the three antigens individually) based on 243 positive controls (defined as >16 days after onset or positive PCR) and 442 negative controls (defined as collected 2019 and earlier) samples.The two included ELISAs were performed according to the manufacturers instructions. The first ELISA used to detect IgG against SARS-CoV-2 (test A, ) was the recomWell SARS-CoV-2 IgG Elisa kit (Mikrogen Diagnostik GmbH, Germany). This assay is an indirect ELISA which uses highly purified recombinant nucleocapsid protein from SARS-CoV-2 as an antigen. The manufacturer had determined the potential interference of antibodies against other pathogens that might induce clinical symptoms similar to those of a SARS-CoV-2 infection (including for example seasonal coronaviruses, influenza A virus, RSV, , ). In addition, they also tested specificity using samples from people with conditions that present with atypical immune system activity including EBV infection, pregnancy, ANA and RF-positive subjects. The cut-off for positivity was calculated according to the manufacturers instructions.The second ELISA test was the EDI Novel Coronavirus COVID-19 IgG Elisa Kit (Epitope Diagnostics, Inc., San Diego, USA) to detect IgG (test B anti-sars-cov-2 rapid test, ). This is an in vitro diagnostic and CE marked indirect ELISA with plates coated with peptides from the SARS-CoV-2 nucleocapsid antigen. Specificity of this assay was determined by the manufacturer using anti-influenza A anti-sars-cov-2 rapid test, anti-influenza B, Hepatitis C virus (HCV), ANA and respiratory syncytial virus (RSV). The cut-off for positivity was determined according to the manufacturers instructions. The manufacturer states that a positive result may be due to past or present infection with SARS-CoV-2 but not due to other coronavirus strains, such as coronavirus HKU1, NL63 anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, OC43, or 229E.Rate of false positive signals were determined as the number of positive samples divided by the total number of samples tested for each assay. Statistical analyses and figures were generated using GraphPad Prism (version 8.2.1). The statistical difference between RF positive and RF negative RA subsets were calculated with Fishers exact test. The other groups were too small to make any meaningful statistical evaluations and thus these results are only presented as descriptive analyses.Serum samples from 47 RA patients (with two samples from one of the patients) anti-sars-cov-2 rapid test, 10 SLE and 10 MS patients were evaluated using 19 SARS-CoV-2 commercial serological assays and compared to an in-house developed multiplex bead-based assay (). Theoverall results of all 68 samples are illustrated in .A total of six commercial LFAs (test G, H, J, K anti-sars-cov-2 rapid test, R and S) reached 100% specificity for both IgG and IgM including all chronic inflammatory disease cohorts patients (=67). Notably anti-sars-cov-2 rapid test, all samples from MS patients (n=10) were negative for both IgM and IgG in all 20 assays. Overview of false positive results in all samples for 19 different serological tests. Six LFA tests (G anti-sars-cov-2 rapid test, H anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test anti-sars-cov-2 rapid test, J, K, R & S) gave no false positive results. The false positivity rate of the remaining tests ranged between 2 - 45%. The test code keys are described in . The two ELISA assays (test A and B) were only tested for IgG.For the 17 LFAs evaluated for specificity using 25 RA samples (from 24 patients of which 20 were treatment nave and 4 were treated with infliximab) that were positive for RF anti-sars-cov-2 rapid test, 10 assays had unspecific signal detected for at least one immunoglobulin isotype ( and ). Five assays had unspecific signal for both IgM and IgG in a few up to a majority of the RA samples (test C: IgM 19/20 anti-sars-cov-2 rapid test, IgG 8/20; test D: IgM 19/20, IgG 2/20; test M: IgM 4/20, IgG 3/20; test N: IgM 6/20, IgG 1/20; and test P: IgM 1/20, IgG 1/20). Unspecific IgM signal anti-sars-cov-2 rapid test, without unspecific IgG signal anti-sars-cov-2 rapid test, was detected in four LFAs (test E: 5/20; test F: 16/20; test O: 20/20; and test Q: 19/20). In one LFA anti-sars-cov-2 rapid test, only the IgG test gave unspecific signal (test L: 1/20). In contrast, only five assays detected unspecific signal in RA samples that were RF negative (= 23), with five detecting IgM and one detecting IgG (test D: IgM 1/23; test F: IgM 1/23; test M: IgM 2/23, IgG 2/23; for test N: IgM 1/23; for test O: IgM 1/23) ( and , for details). None of the two ELISAs (test A and B) gave any false positive signals with these samples. Due to insufficient sample volume anti-sars-cov-2 rapid test, these ELISA tests could not be verified as extensively as the other tests ( for details). Percentage of the false positive test results for IgM antibodies against SARS-CoV-2. Samples from MS patients (n=10), DMARD nave RF positive RA patients (n= 20), RF negative (n=20) RA patients, SLE patients (n=10), infliximab treated RA patients (n=8). The test code keys are described in . Stars indicate significant difference between RF status in RA patients, using Fisher exact test, *p < 0.05, ****p < 0.0001. Pos, positive; neg, negative; n, number; RF, rheumatoid factor; IFX, infliximab; n/a, not applicable; RA, rheumatoid arthritis; MS, multiple sclerosis; SLE, systemic lupus erythematosus. Percentage of the false positive test results for IgG. Samples from MS patients (n=10), DMARD nave RF positive RA patients (n= 20), RF negative (n=20) RA patients, SLE patients (n=10) anti-sars-cov-2 rapid test, infliximab treated RA patients (n=8). The test code keys are described in . Pos, positive; neg anti-sars-cov-2 rapid test, negative; n, number; RF, rheumatoid factor; IFX, infliximab; n/a, not applicable; RA, rheumatoid arthritis; MS anti-sars-cov-2 rapid test, multiple sclerosis; SLE, systemic lupus erythematosus.When using IFX treated-RA patients as SARS-CoV-2 serology negative controls (patients =7, samples =8) (), unspecific signal was detected for IgM in seven assays (test D: 1/8; test E: 1/8; test F:1/8 test I: 3/8; test N: 2/8; test O: 4/6; and test P: 3/6) and for IgG () in two assays (test B: borderline positive signal in 2/2 samples and test P: 3 of 6 samples). Two samples were from one individual at two time points; prior to second infliximab infusion and after 9 months on treatment initiation. These two samples (IFX1 and IFX2 in ) were both borderline positive in test B, and the sample taken after 9 months (IFX1) was positive in test E for IgM only.False positive signal were detected in one ELISA test for IgG, five IgM LFAs and four IgG LFAs using the 10 SLE samples. All of these were ANA positive and four were anti-dsDNA positive (). Three of the SLE patients were IgA RF positive and one IgG RF positive. Five SLE patients had anti-rituximab ADA. There was no obvious pattern of associations to any of these antibodies with false positive signal in the SARS-CoV-2 serology assays.The levels of IgG, IgM and IgA RF werevery high in the RF positive RA samples (n=20), as these had been selected as such. Thus anti-sars-cov-2 rapid test, associations between specific RF isotypes and false positive IgM/IgG anti-SARS-CoV-2 response could not be analyzed. Some indications could be retrieved from the SLE samples (n=10) who had a diversity of RF isotypes, i.e. none of the patients had IgM RF, three had IgA RF and one was positive for IgG RF. No associations were identified between RF isotypes and false positive anti-SARS-CoV-2 IgM or IgG signal in the SLE samples. However, there was a higher level of IgA RF and absence of false positive IgM/IgG anti-SARS-CoV-2 in two samples (SLE2 with 551 IU/ml and SLE7 with 26 IU/ml respectively in ). These two samples were negative in all SARS-CoV-2 tests. Another two samples (SLE1 and SLE8 in ) were negative for IgA RF but gave the highest number of false positive signals in SARS-CoV-2 tests. We also found that one RF negative SLE sample was IgM positive in two tests (C and N) and another RF negative SLE sample was both IgM and IgG positive in two tests (O and P). No associations were identified between anti-CCP2 antibodies or C1q-binding immune complexes and false positive IgM/IgG anti-SARS-CoV-2 response.Due to insufficient sample volume only 66 of the 68 samples were analyzed using the in-house developed multiplex bead-based assay for IgG detection as described above (). All samples analyzed using this method were classified as negative. The only two samples not included were the two infliximab treated samples from the same patient ().Serological assays are necessary tools in a pandemic, both for determining the proportion of the population already subjected to the infection and for the individual to confirm past infection and present immunity. In the case of SARS-CoV-2, it seems that a small proportion of the individuals who have been infected do not develop antibodies, at least not as determined by currently available serological assays (). It also appears that some might have pre-existing immunity present in the population, as determined by memory T cell reactivity ( anti-sars-cov-2 rapid test, ) and the estimated prevalence of infected individuals in comparisons to the proportion that succumb in severe disease ().To elucidate these issues, we have to rely on the serological assays. Therefore, an independent verification of sensitivity and specificity of such assays is often required. These two are interconnected and a higher sensitivity often results in a lower specificity and vice versa. The diagnostic specificity of an assay is defined as the ability to correctly assign negative samples as negative. It can be determined by using a selection of samples negative for the new infection and positive for a range of other infections which might give cross-reactivity in the assay. Typically, the negativity for this pandemic can be guaranteed by having samples collected before SARS-CoV-2 emerged. When serological assays against viral antigen are developed, one major concern is regarding the cross-reactivity against similar viruses (). SARS-CoV-2 serological assays using antigens that cross-react with antibodies generated towards other coronaviruses will not be approved, since the lower specificity would not serve the purpose of answering the clinically and epidemiologically important questions of who has developed antibodies against the new virus.The aspect of immunity against SARS-CoV-2 is of particular importance to persons with chronic inflammatory diseases, given the concerns that treatments or their underlying disease might render them less able to fight the infection, establish immunity or respond to vaccinations. It is possible that only a few viral serology assays on the market will have tested for interferences using serum from patients with chronic inflammatory diseases. This may be because the priority is to ensure the assay as virus-specific in the sense of not cross-reacting with other viral infections. Alternatively, this may be because these types of patient sera are not easily accessible for manufacturers to be tested.However, sera from patients with autoimmune diseases are notorious for interfering in immunological assays, giving higher background and unspecific signals. For instance, in the drug immunogenicity field, when validating assays for determining ADA, it is recommended to account for such unspecific signal during assay development and validation. This is achieved using a cohort of baseline samples in clinical trials from the targeted patient population who are treatment naive to the biological drug for which the ADA assay is developed (, ). For serological assays used to detect viral infections, such interference might not be discovered until more extensive screening of larger populations is started. This would become particularly notable anti-sars-cov-2 rapid test, and give a false impression of exposure and immunity anti-sars-cov-2 rapid test, if there is an interference by serum factors from patients with common diseases that have a frequency in the same magnitude as the studied infection. These serum factors could include autoantibodies, biological drugs anti-sars-cov-2 rapid test, ADA, or aggregates and immune complexes formed e.g. by one or several of these components together. To complicate the matter further, there are indications that SARS-CoV-2 infection and COVID-19 disease might trigger these autoantibodies ().In the present study, a selection of samples from patients with chronic inflammatory diseases was used to determine the molecular specificity of a range of SARS-CoV-2 serological assays. We found that false positive results occur in the majority of the serological assays evaluated (). Most notably, samples from RA patients with high levels of RF of IgM and IgG isotype resulted in a false positive signal in several assays ( and ). As RF binds to the constant parts of IgG anti-sars-cov-2 rapid test, this could precipitate other antibodies present in an immunoassay in an unspecific way. These unspecific positive signals might not only give false indication of protective immunity to SARS-CoV-2 for an individual with RF but might also give an incorrect picture of the proportion of the population exposed to the infection during larger screenings anti-sars-cov-2 rapid test, especially if the diagnoses or RF status of the population from where samples were collected are unknown. Most of the false positive signals were detected in the IgM assays, as has been noted by others (, ) anti-sars-cov-2 rapid test, which might be in line with the broader low affinity quality of the IgM antibodies, as compared to IgG class switched and affinity matured antibodies. Other studies have reported about this issue with different interpretations. One study using only one test (Innovita Biotechnology Co, Tangshan, China) reported that there was no interference with serum from persons with autoimmune disease (), which we can confirm here for the Innovita LFA (test S).Serum from patients with SLE has a high abundance of autoantibodies, including RF, ANA and antibodies against dsDNA. However, many other targets have also been described and the isotypes and specificities of these autoantibodies correlates with the symptoms of the disease (). Although SLE is a less prevalent disease than RA, serum samples from these patients contributed essentially to the false positive signals in the present study.Rheumatoid factor was the first autoantibody described in RA. According to different studies anti-sars-cov-2 rapid test, RF has limited specificity for RA (from 48% to 92%) (), since it can also be present in healthy controls and patients with other autoimmune and non-autoimmune diseases, such as chronic infections and cancer, and now also in COVID-19 survivors (, ). Since RF is heterophilic and can involve different immunoglobulin classes (IgM anti-sars-cov-2 rapid test, IgG and IgA), we characterized these further. IgM-RF is the isotype commonly measured in most clinical laboratories, and detected in 60-80% of RA patients (, ) anti-sars-cov-2 rapid test, but might appear also in other diseases ( anti-sars-cov-2 rapid test, , ). In the current study, we were not able to evaluate any specific associations between occurrence of RF IgM or RF IgG and false po anti-sars-cov-2 rapid test