Investigation of serological response to COVID-19 among healthcare workers using four different kits.

Objective: This study aimed to investigate the serological response to SARS-CoV-2 among healthcare workers at a hospital in Turkey using kits from four different companies. Methods: The study included 120 healthcare workers who received the Sinovac vaccine at a Turkish hospital. Serum samples were collected from these participants who had received the Sinovac vaccine at a median of 1 month after administration of the second dose. Samples were tested using the Abbott SARSCoV-2 IgG II Quant, Beckman Coulter Access SARS-CoV-2 IgG, Maglumi 2019-nCoV IgG, and Siemens Advia Centaur SARS-CoV-2 IgG test kits. In the presented comparative study, the results of the different immunoassay analyzers were compared. Relationships among the results were evaluated by comparing the levels of antibodies against spike proteins. Results: The results of the antibody analyses differed according to the kits that were used. The Abbott SARS-CoV-2 IgG II Quant test was positive for 44.17% and negative for 55.83% of the participants, the Access SARS-CoV-2 IgG test was positive for 80.83% and negative for 19.17%, the Maglumi 2019-nCoV IgG test was negative for 55% and positive for 45%, and the Advia Centaur SARS-CoV-2 IgG test was positive for 88.83% and negative for 11.67%. The number of participants who tested positive when the Abbott kit was used differed significantly compared to other analysis kits (p<0.0001). The difference between the Beckman Coulter and Maglumi kits was not significant (p>0.37), but the difference between the Maglumi and Siemens kits was significant, with the positivity rate of the Siemens kit being significantly higher (p<0.0001). Conclusion: This study has confirmed that serological tests produced by different manufacturers can be used to identify individuals exposed to the COVID-19 virus and to assess the exposure rate of the community. [ABSTRACT FROM AUTHOR]