COVID-19 Antibodies are Detectable Upto a Year After Infection

Scientists from the USA have recently investigated the durability and robustness of SARS-CoV-2 antibodies. The findings currently published on a pre-print server revealed that COVID-19 patients exhibit a strong anti-SARS-CoV-2 antibody response for up to 1 year. The study included 505 patients (both hospitalized and non-hospitalized) who were enrolled for the study and evaluated for anti-SARS-CoV-2 antibody response. The patients were divided into three age groups: 18 – 44 years; 45 – 64 years; and more than 65 years. The patients who had been hospitalized were considered to have moderate to severe COVID-19. 

The study findings revealed that 100% of hospitalized patients were present with anti-SARS-CoV-2 antibody response even after one year of symptom onset. Among non-hospitalized patients, about 95% and 80% remained seropositive 6 months and 12 months after the symptom onset, respectively. The half-life of binding antibodies in both hospitalized and non-hospitalized patients was found to be more than 1000 days after the symptom onset. During the early infection phase, hospitalized patients exhibited significantly higher antibody levels than non-hospitalized patients. However, after 12 months of infection, this difference in antibody response was abolished. Two different neutralization assays were carried by the scientists to determine the duration and efficacy of anti-SARS-CoV-2 neutralizing antibodies.

In one experiment, the half-life of neutralizing antibodies in hospitalized and non-hospitalized patients was found to be 88 days and 77 days, respectively. Whereas, in the other experiment, the half-life was estimated to be 106 days and 29 days in hospitalized and non-hospitalized patients, respectively. The half-life of binding antibodies in non-hospitalized patients aged 18 – 44 years, 45 – 64 years, and more than 65 years were estimated to be 1000 days, 230 days, and 143 days, respectively. However, a half-life of 1000 days was detected in hospitalized patients across all age groups.

Ref link: https://www.medrxiv.org/content/10.1101/2021.04.27.21256207v1