Journal of clinical microbiology
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J. Clin. Microbiol. · Jul 2020
Comparative StudyPerformance Characteristics of Four High-Throughput Immunoassays for Detection of IgG Antibodies against SARS-CoV-2.
The role of serologic testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in both the clinical and public health settings, will continue to evolve as we gain increasing insight into our immune response to the virus. Here, we evaluated four high-throughput serologic tests for detection of anti-SARS-CoV-2 IgG antibodies, from Abbott Laboratories (Abbott Park, IL), Epitope Diagnostics, Inc. (San Diego, CA), Euroimmun (Lubeck, Germany), and Ortho-Clinical Diagnostics (Rochester, NY), using a panel of serially collected serum samples (n = 224) from 56 patients with confirmed coronavirus disease 2019 (COVID-19), healthy donor sera from 2018, and a cross-reactivity serum panel collected in early 2020. The sensitivities of the Abbott, Epitope, Euroimmun, and Ortho-Clinical IgG assays in convalescent-phase serum samples collected more than 14 days post-symptom onset or post-initial positive reverse transcriptase PCR (RT-PCR) result were 92.9% (78/84), 88.1% (74/84), 97.6% (82/84), and 98.8% (83/84), respectively. ⋯ Overall assay specificity/positive predictive values based on a 5% prevalence rate were 99.6%/92.8%, 99.6%/90.6%, 98.0%/71.2%, and 99.6%/92.5%, respectively, for the Abbott, Epitope, Euroimmun, and Ortho-Clinical IgG assays. In conclusion, we show high sensitivity in convalescent-phase sera and high specificity for the Abbott, Euroimmun, and Ortho-Clinical anti-SARS-CoV-2 IgG assays. With the unprecedented influx of commercially available serologic tests for detection of antibodies against SARS-CoV-2, it remains imperative that laboratories thoroughly evaluate such assays for accuracy prior to implementation.
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J. Clin. Microbiol. · Jul 2020
Comparative StudyPerformance of Abbott ID Now COVID-19 Rapid Nucleic Acid Amplification Test Using Nasopharyngeal Swabs Transported in Viral Transport Media and Dry Nasal Swabs in a New York City Academic Institution.
The recent emergence of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has posed formidable challenges for clinical laboratories seeking reliable laboratory diagnostic confirmation. The swift advance of the crisis in the United States has led to Emergency Use Authorization (EUA) facilitating the availability of molecular diagnostic assays without the more rigorous examination to which tests are normally subjected prior to FDA approval. Our laboratory currently uses two real-time reverse transcription-PCR (RT-PCR) platforms, the Roche Cobas SARS-CoV2 and the Cepheid Xpert Xpress SARS-CoV-2. ⋯ In search for a platform with a shorter turnaround time, we sought to evaluate the recently released Abbott ID Now COVID-19 assay, which is capable of producing positive results in as little as 5 min. We present here the results of comparisons between Abbott ID Now COVID-19 and Cepheid Xpert Xpress SARS-CoV-2 using nasopharyngeal swabs transported in viral transport media and comparisons between Abbott ID Now COVID-19 and Cepheid Xpert Xpress SARS-CoV-2 using nasopharyngeal swabs transported in viral transport media for Cepheid and dry nasal swabs for Abbott ID Now. Regardless of method of collection and sample type, Abbott ID Now COVID-19 had negative results in a third of the samples that tested positive by Cepheid Xpert Xpress when using nasopharyngeal swabs in viral transport media and 45% when using dry nasal swabs.
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J. Clin. Microbiol. · Jul 2020
Comparative StudyEvaluation of the COVID-19 IgG/IgM Rapid Test from Orient Gene Biotech.
While the coronavirus disease 2019 (COVID-19) pandemic has peaked in many countries already, the current challenge is to assess population immunity on a large scale. Many serological tests are available and require urgent independent validation. Here, we report performance characteristics of Orient Gene Biotech COVID-19 IgG/IgM Rapid Test Cassette (OG) and compare it to Abbott SARS-CoV-2 IgG immunoassay (ASIA). ⋯ Specificity was 100% (CI95%, 93.4 to 100) with both tests on samples, including patients infected with endemic coronavirus. Overall, OG performance characteristics indicate that the test is suitable for routine use in clinical laboratories, and its performance is equivalent to that of immunoassay. Testing OG on a larger asymptomatic population may be needed to confirm these results.
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J. Clin. Microbiol. · Jul 2020
Review Comparative StudyComparative Pathogenesis of Bovine and Porcine Respiratory Coronaviruses in the Animal Host Species and SARS-CoV-2 in Humans.
Discovery of bats with severe acute respiratory syndrome (SARS)-related coronaviruses (CoVs) raised the specter of potential future outbreaks of zoonotic SARS-CoV-like disease in humans, which largely went unheeded. Nevertheless, the novel SARS-CoV-2 of bat ancestral origin emerged to infect humans in Wuhan, China, in late 2019 and then became a global pandemic. Less than 5 months after its emergence, millions of people worldwide have been infected asymptomatically or symptomatically and at least 360,000 have died. ⋯ BCoV also has a dual tropism for the respiratory and gastrointestinal tracts. These aspects, their interspecies transmission, and certain factors that impact disease severity in cattle parallel related facets of SARS-CoV or SARS-CoV-2 in humans. PRCV has a tissue tropism for the upper and lower respiratory tracts and a cellular tropism for type 1 and 2 pneumocytes in lung but is generally a mild infection unless complicated by other exacerbating factors, such as bacterial or viral coinfections and immunosuppression (corticosteroids).
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J. Clin. Microbiol. · Jul 2020
Comparative StudyComparison of Four Molecular In Vitro Diagnostic Assays for the Detection of SARS-CoV-2 in Nasopharyngeal Specimens.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the novel human coronavirus that causes coronavirus disease 2019 (COVID-19), was first discovered in December 2019 as the cause of an outbreak of pneumonia in the city of Wuhan, Hubei province, China. The clinical presentation of COVID-19 is fairly nonspecific, and symptoms overlap those of other seasonal respiratory infections concurrently circulating in the population. ⋯ In the present study, we evaluated the analytical sensitivity and clinical performance of the following four SARS-CoV-2 molecular diagnostic assays granted emergency use authorization by the FDA using nasopharyngeal swabs from symptomatic patients: the New York SARS-CoV-2 Real-time Reverse Transcriptase (RT)-PCR Diagnostic Panel (modified CDC) assay, the Simplexa COVID-19 Direct (Diasorin Molecular) assay, GenMark ePlex SARS-CoV-2 (GenMark) assay, and the Hologic Panther Fusion SARS-CoV-2 (Hologic) assay. This information is crucial for both laboratories and clinical teams as decisions on which testing platform to implement are made.