Abstract Knowledge of the level and duration of protective immunity against SARS‐CoV‐2 after primary infection is of crucial importance for preventive approaches. Currently, there is a lack of evidence on the persistence of specific antibodies. We investigated the generation and maintenance of neutralizing antibodies of convalescent SARS‐CoV‐2‐afflicted patients over a ten‐month period post‐primary infection using an immunofluorescence assay, a commercial chemiluminescent immunoassay and an in‐house enzyme‐linked neutralization assay. We present the successful application of an improved version of the plaque‐reduction neutralization assay which can be analysed optometrically to simplify data interpretation. Based on the results of the enzyme‐linked neutralization assay, neutralizing antibodies were maintained in 77.4% of convalescent individuals without relevant decay over ten months. Furthermore, a positive correlation between severity of infection and antibody titre was observed. In conclusion, SARS‐CoV‐2‐afflicted individuals have been proven to be able to develop and maintain neutralizing antibodies over a period of ten months after primary infection. Findings suggest long‐lasting presumably protective humoral immune responses after wild‐type infection.
【저자키워드】 Immunity, SARS‐CoV‐2, IgG antibodies, persistence, neutralization test, 【초록키워드】 neutralizing antibody, Neutralizing antibodies, Infection, SARS‐CoV‐2, Neutralization assay, protective immunity, immunofluorescence assay, immune responses, Patient, humoral immune response, chemiluminescent immunoassay, convalescent, Protective, specific antibodies, Antibody titre, Primary infection, Evidence, maintenance, approaches, individual, positive correlation, Severity of infection, finding, convalescent individuals, data interpretation, convalescent individual, lack, develop, investigated, analysed, maintain, 【제목키워드】 neutralizing antibody, SARS‐CoV‐2, Patient, convalescent,