Time dependent decline of neutralizing antibody titers in COVID-19 patients from Pune, India and evidence of reinfection.

Purpose: To assess modulation of neutralizing antibody titers in COVID-19 patients and understand association of variables such as age, presence of comorbidity, BMI and gender with antibody titers.

Methods: Patients (n = 100) diagnosed from 20th March 2020 to 17th August 2020 and treated at two large hospitals from Pune, India were included and followed up (clinical and serologic) for varied periods. IgG-anti-SARS-CoV-2 (Spike protein-based ELISA) and neutralizing antibody titers (NAb, PRNT) were determined in all the samples.