key: cord-0843472-5dov14wy authors: Choe, Jung‐Yoon; Kim, Ji‐Won; Kwon, Hyun Hee; Hong, Hyo‐Lim; Jung, Chi Young; Jeon, Chang‐Ho; Park, Eun‐Jin; Kim, Seong‐Kyu title: Diagnostic performance of immunochromatography assay for rapid detection of IgM and IgG in coronavirus disease 2019 date: 2020-06-09 journal: J Med Virol DOI: 10.1002/jmv.26060 sha: 7fafc7d8eae5dc2162c27ffdb640047f2fe73ea7 doc_id: 843472 cord_uid: 5dov14wy Serologic assays have been developed to detect infection with coronavirus disease 2019 (COVID‐19). This study was conducted to evaluate the diagnostic performance of an immunochromatography‐based assay of human serum for COVID‐19. The present study enrolled 149 subjects who had been tested by real‐time reverse transcription‐polymerase chain reaction (RT‐PCR) for COVID‐19 and were classified into two groups: 70 who were positive for COVID‐19 and 79 who were negative for COVID‐19 based on RT‐PCR. An immunochromatography‐based COVID‐19 immunoglobulin G (IgG)/immunoglobulin M (IgM) rapid test on the sera of the study population was applied to measure the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) curve compared to RT‐PCR, with a 95% confidence interval (CI). IgM or IgG antibodies were detected in 65 subjects (92.9%) classified as positive for COVID‐19 and in three subjects (3.8%) classified as negative for COVID‐19. The sensitivity and specificity percentages for IgM or IgG antibodies were 92.9% (95% CI: 84.1‐97.6) and 96.2% (95% CI: 89.3‐99.2), respectively, with 95.6% PPV and 93.8% NPV. The PPV rapidly improved with increasing disease prevalence from 19.8% to 96.1% in the presence of either IgM or IgG, while the NPV remained high with a change from 99.9% to 93.1%. The area under the ROC curve was 0.945 (95% CI: 0.903‐0.988) for subjects with either IgM or IgG positivity. In conclusion, the immunochromatography‐based COVID‐19 IgG/IgM rapid test is a useful and practical diagnostic assay for detection of COVID‐19, especially in the presence of IgM or IgG antibodies. RT-PCR. An immunochromatography-based COVID-19 immunoglobulin G (IgG)/immunoglobulin M (IgM) rapid test on the sera of the study population was applied to measure the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) curve compared to RT-PCR, with a 95% confidence interval (CI). IgM or IgG antibodies were detected in 65 subjects (SARS-CoV-2). 2 The disease is also referred to as coronavirus disease 2019 . 3 The global mortality rate of COVID-19 was reported to range from 1.5% to 3.6%. 4 Currently, the diagnosis of COVID-19 has been confirmed using next-generation sequencing or real-time reverse Baseline characteristics of the study population were described at and headache in positive COVID-19 group was higher than that of the negative group (P = .009, P < .001, P < .001, and P = .031, respectively). In the analysis of immmunochromatography for COVID -19, there were no subjects in the RT-PCR positive group and two subjects (2.5%) in the RT-PCR negative group who only produced the IgM antibody (Table 2 ). In addition, 19 patients ( Figure 1A) . A gradual decrease in NPV of either IgM or IgG positivity from 99.9% to 95.3% was observed with increasing from 1% to 50% disease prevalence ( Figure 1B The WHO announced that Chinese authorities had identified a novel type of coronavirus on 7 January 2020. 9 Presently, RT-PCR, a nucleic acid amplification test (NAAT), has been routinely used to detect COVID-19 infection in many countries around the world. 1, 2, 5, 6 In this study, we assessed the diagnostic value of a new immunochromatography assay to detect IgM and IgG antibodies for However, there are some limitations or weaknesses in the areas of confirmation of COVID-19 diagnosis by RT-PCR testing alone, such as the inability to distinguish virus viability and production of indeterminate or false-negative results due to low numbers of target cells in specimens, although RT-PCR remains a powerful technique for microbial diagnostics. 14 Laboratory assays such as ELISA and immunochromatography that use serum or blood sampled from suspected or established patients with COVID-19 infection have been proposed to overcome or supplement these limitations. One study using In-house anti-SARSr-CoV IgG and IgM ELISA to target the N gene showed that the IgM antibody level increased rapidly in the early stages of COVID-19 infection and then decreased in the later stages. 13 Furthermore, the IgG antibody was insignificantly expressed in the early stages of infection but increased rapidly in the later stages. Interestingly, titers of both IgM and IgG antibodies in COVID-19 patients were significantly higher than those assessed in healthy subjects. Infections have been reported to be reactivated in patients and confirmed by RT-PCR testing. 15 Therefore, serial quantitative results using ELISA may help not only confirm the diagnosis but also predict the clinical course of a patient. Immunochromatography is another diagnostic alternative that has been proposed to detect COVID-19 infection. This technique was developed in the late 1960s to detect antigens in the blood and has recently been used as a rapid diagnostic method for various viral infections, such as Norovirus and influenza. 16, 17 The benefits or advantages of immunochromatography include its ability to be performed at bedside without special laboratory equipment, its ease of performance, its simple interpretation, and its rapid time to produce results, which may compare favorably to other diagnostic tools, such as RT-PCR and ELISA methods. There are some limitations to this study. First, it was not possible to observe changes in antibodies from the time of patient diagnosis to the time of participation in the study because this study was conducted in a cross-sectional manner. Second, the quantitative titer for each antibody expressed in the test kit could not be confirmed and is, therefore, a methodological limitation of immunochromatography. Third, it may be difficult to fully represent the diagnostic values, especially the sensitivity and specificity, of the diagnostic kit due to the small size of the study population. In conclusion, immunochromatography demonstrated higher Clinical features of patients infected with 2019 novel coronavirus in Wuhan Genomic characterisation and epidemiology of 2019 novel coronavirus: implications for virus origins and receptor binding World Health Organization. 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Novel Coronavirus (2019-nCoV) situation report-1 Emerging coronaviruses: genome structure, replication, and pathogenesis Characterization of spike glycoprotein of SARS-CoV-2 on virus entry and its immune cross-reactivity with SARS-CoV Detection of 2019 novel coronavirus (2019-nCoV) by real-time RT-PCR A pneumonia outbreak associated with a new coronavirus of probable bat origin A basic guide to real time PCR in microbial diagnostics: definitions, parameters, and everything Clinical characteristics of severe acute respiratory syndrome coronavirus 2 reactivation Sequential evolution of genotype GII.4 norovirus variants causing gastroenteritis outbreaks from 2001 to 2006 in Eastern Spain Evaluation of QuickVue influenza A+B rapid test for detection of pandemic influenza A/H1N1 Evaluation of an immunochromatography method for rapid detection of noroviruses in clinical specimens in Thailand Detection methods of human and animal influenza virus-current trends The authors declare that there are no conflict of interests. https://orcid.org/0000-0003-0957-0395Ji-Won Kim https://orcid.org/0000-0002-0498-5762Hyun Hee Kwon https://orcid.org/0000-0002-8509-3968Hyo-Lim Hong https://orcid.org/0000-0003-2147-1381Chi Young Jung https://orcid.org/0000-0002-8958-0886Chang-Ho Jeon https://orcid.org/0000-0002-7450-7117Eun-Jin Park https://orcid.org/0000-0001-7137-6150Seong-Kyu Kim https://orcid.org/0000-0002-7780-0167