CORONAVIRUS TIMELINE

(Part 3)

This article is Coronavirus Timeline Part 3. To visit Coronavirus Timeline Part 2 click here.

June 2, 2021: Prior SARS-CoV-2 infection rescues B and T cell responses to variants after first vaccine dose. A boost from infection. During clinical trials of severe acute respiratory syndrome coronavirus 2 vaccines, no one who had survived infection with the virus was tested. A year after the pandemic was declared, vaccination of previously infected persons is a reality. Reynolds et al. address the knowledge gap in a cohort of UK health care workers given the Pfizer/BioNTech vaccine in which half of the participants had experienced natural virus infections early in the pandemic (see the Perspective by Crotty). Genotyping indicated that a genetic component underlies heterogeneity in immune responses to vaccine and to natural infection. After vaccination, naïve individuals developed antibody responses similar to those seen in naturally infected persons, but T cell responses were more limited and sometimes absent. However, antibody and memory responses in individuals vaccinated after infection were substantially boosted to the extent that a single vaccine dose is likely to protect against the more aggressive B.1.1.7 variant. It is possible that the messenger RNA vaccine has an adjuvant effect, biasing responses toward antibody generation.
Next

This ends Coronavirus Timeline Part 3. To continue reading please visit Coronavirus Part 4 here.