Assay dependence of long-term kinetics of SARS-CoV-2 antibodies

Since the worldwide outbreak of the novel coronavirus (SARS-CoV-2), the question raised whether infected patients would elicit long-lasting protective immunity. Several companies developed serological assays for the detection of SARS-CoV-2 antibodies. In this study, we compared 4 different serology assays in convalescents up to 7 months post-infection. Both Abbott assays showed a significative decrease of IgG antibodies over time. Whereas the Elecsys Anti‑SARS‑CoV‑2 N assay (Roche) initially showed a significant increase, antibody titers significantly decreased at the latest timepoint. Although not significant, the Elecsys Anti‑SARS‑CoV‑2 S assay (Roche) showed tendency towards increasing titers overtime. Our data showed that results of SARS-CoV-2 serology should be interpreted with caution.