How much immunity do we need against COVID-19? New international research has identified a "threshold of immunity" to SARS-CoV-2. The study has identified strong relationships between Receptor-binding domain (RBD) COVID19 antibodies, and how well humans can neutralize the SARS-CoV-2 virus. A RBD is a key part of a virus that allows it to dock to body receptors to gain entry into cells, leading to infection. These are also the primary targets in the prevention and treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)—the virus that causes COVID-19. This new research, coordinated by Dr. Grace M. Kenny and Sophie O'Reilly...