Researchers from the Icahn School of Medicine at Mount Sinai have found that most COVID-19 patients have persistent antibodies to the SARS-CoV-2 virus at levels that are correlated with neutralization of the virus more than a year after acute infection. The study also showed that patients with more severe disease had higher rates of antibody positivity over time than those with less severe disease.
Severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) infection elicits a humoral immune response characterized by neutralizing antibodies against the spike protein. While prior studies have demonstrated detectable antibodies against SARS-CoV-2 infection for a few months post-infection, there has been no consistent data regarding the long-term persistence of protective antibody titers.
To address this information gap, Mount Sinai researchers investigated the longevity of SARS-CoV-2 antibody response in a cohort of more than 600 patients who were part of The Mount Sinai Post COVID-19 Registry and who received care for COVID-19 in the outpatient, emergency department and inpatient hospital settings within the Mount Sinai Health System in New York City between July 2020 and April 2021. Study participant had laboratory confirmed COVID-19 infection and had not received vaccination prior to enrollment or during the study period.
The Mount Sinai COVID-19 Registry is a system-wide initiative that is currently enrolling patients who have previously been diagnosed with COVID-19 and/or are currently hospitalized for acute COVID-19, as well as a sample of matched COVID-19 negative controls. The goal of the registry is to investigate the long-term effects of SARS-CoV-2 infection.
For this study, the research team administered 1,195 antibody tests using an enzyme-linked immune-sorbent assay (ELISA) to assess SARS-CoV-2 antibodies from at least 30 days to up to 13 months after acute infection. Overall, 90 percent and 83 percent of patients had positive antibody tests at 6 and 13-months post COVID-19, respectively.
“Understanding immunological memory post COVID-19 can provide insights into the risk for reinfection and the potential durability of vaccines,” says Juan Wisnivesky, MD, MPH, Professor of Medicine and Chief of the Division of General Internal Medicine at the Icahn School of Medicine at Mount Sinai and corresponding author of the study. “Our finding that most COVID-19 patients have high antibody titers more than a year post-infection is an important piece of information towards better understanding of this virus. Additional research is necessary and is currently being conducted to determine whether these antibodies provide protection against reinfection.”
The findings are published on August 3, 2021, in the Journal of General Internal Medicine.