Detecting Waning Serological Response with Commercial Immunoassays: 18-Month Longitudinal Follow-up of Anti-SARS-CoV-2 Nucleocapsid Antibodies
Yu Nakagama, Yuko Komase, Natsuko Kaku, Yuko Nitahara, Evariste Tshibangu‐Kabamba, Tomoyo Tominaga, Hiroko Tanaka, Tomoaki Yokoya, Minako Hosokawa, Yasutoshi Kido
Abstract
Past SARS-CoV-2 infection is an important determinant of protection from reinfection and of postvaccine immune responses. Our results show that different immunoassays, by design, harbor variable capability of tracking SARS-CoV-2 infection under waning antibody concentrations. With each recovered patient standing at a unique time point along the decline curve of antibodies, precise estimation of COVID-19 cumulative incidence remains a challenge. Since future surveillance studies will be targeting more than ever heterogenous cohorts, selecting the appropriate immunoassay is crucial in order to assure reliable decisions about an individual's previous infection status.