COVID-19 Impacts Immune Response and Long-Term Health Risks.

Stanford University researchers have found that people who contracted COVID-19 before getting vaccinated appear to have damaged a key part of their immune-cell response, with a "major reduction" in the body's quantity and quality of CD8+ T cells. The study analyzed blood samples from three groups of volunteers and found that people who had survived a COVID-19 infection before vaccination produced spike-specific CD8+ T cells at considerably lower levels compared to vaccinated people who had never been infected. Researchers emphasized the need to develop vaccination strategies to specifically boost antiviral CD8+ T-cell responses in people previously infected with COVID-19.