Rapid cassette test results in anti-SARS-CoV-2 antibody screening verification by electrochemiluminescence immunoassay method

Abstract

Objective: Since the resumption of face-to-face education in October 2020, which was suspended due to the COVID-19 pandemic, coincides with the period when SARS-CoV-2 infection rates in young adults are on the rise. This study focuses on the 2019 corona virus outbreak in young adults, the largest link in the chain of transmission, which can be defined as silent contagious agents. It is aimed to provide epidemiological data by detecting virus disease (COVID-19) seropositivity with two different serological methods, and to evaluate the symptom-test performance relationship of asymptomatic/mild symptom/symptomatic cases. Methods: A cross-sectional study was conducted with students studying at Cappadocia University health programs between December 2020 and February 2021 and who will attend practice courses face-to-face. Participants were surveyed about their COVID-19 symptoms and disease histories based on SARS-CoV-2 exposure. For SARS-CoV-2 antibody detection, blood samples were taken from the participants and investigated with a single lateral flow immunoAssay (LFIA, Novatech, Turkey) cassette test. The samples with positive test result were then SARS-CoV-2 Anti-N IgM+IgG;SARS-CoV-2 Anti-S IgM+IgG;SARS-CoV-2 Anti-RBD IgG;It was re-evaluated using the electrochemiluminescence immunoassay (ECLIA) method with the anti-SARS-CoV-2 kit (Roche, Germany). Results: Of the 239 samples participating in the study, 50 (20.9%) samples that were positive for SARS-CoV2 IgM/ IgG according to the LFIA method were then studied again with the ECLIA method. According to the ECLIA result, 72% (36/50) of individuals against both nucleocapsid (N) and spike (S) antigens, and 70% (35) against RBD antigen were seropositive. Based on the ECLIA test results, 239 samples were studied and 50 samples were found to be IgM/IgG positive, with a sensitivity of 64% and a specificity of 93%. Contingence history was reported in 46% (n=23) of patients who were seropositive by both methods, while 30% (n=15) showed a COVID-19 clinic. Fifty four percent (n=27) of the participants reported that they did not have a PCR (polymerase chain reaction) test, but antibody response was observed in all of them. Only 28% (n=14) of seropositive patients reported positive PCR results, and 4% of them stated that they had a chronic disease. It will be important to continue to observe the serological status of young people, particularly in the context of new COVID-19 variants and in the low interest in mass vaccination campaigns targeting young people. Conclusion: It is thought that the performance of ECLIA with rapid casette test does not have a good degree of agreement and confirmation with different immunoassay tests would be more useful for epidemiological surveillance. Especially the new COVID-19 in the context of the variants and targeting youth due to the lack of interest in vaccination champaigns continue to monitor the serological status of young people it will be important.