- The immune systems of more than 95% of people who recovered from COVID-19 had durable memories of the virus up to 8 months after infection.
- The results provide hope that people receiving SARS-CoV-2 vaccines will develop similar lasting immune memories after vaccination.
After people recover from infection with a virus, the immune system retains a memory of it. Immune cells and proteins that circulate in the body can recognize and kill the pathogen if it’s encountered again, protecting against disease and reducing illness severity.
This long-term immune protection involves several components. Antibodies recognize foreign substances like viruses and neutralize them. Different types of T cells help recognize and kill pathogens. B cells make new antibodies when the body needs them.
All of these immune-system components have been found in people who recover from SARS-CoV-2, the virus that causes COVID-19. But the details of this immune response and how long it lasts after infection have been unclear. Scattered reports of reinfection with SARS-CoV-2 have raised concerns that the immune response to the virus might not be durable.
To better understand immune memory of SARS-CoV-2, researchers led by Daniela Weiskopf, PhD, from the La Jolla Institute for Immunology analyzed immune cells and antibodies from almost 200 people who had been exposed to SARS-CoV-2 and recovered.
Time since infection ranged from 6 days after symptom onset to 8 months later. More than 40 participants had been recovered for more than 6 months before the study began. About 50 people provided blood samples at more than one time after infection.
Source: Dan JM, Mateus J, Kato Y, et al. Immunological memory to SARS-CoV-2 assessed for up to 8 months after infection. Science. 2021 Feb 5;371(6529):eabf4063.