Youth, Delta variant behind UK COVID surge

Two new studies look at the Delta variant (B1617) behind the UK COVID-19 surge, with the first noting that young people are helping drive the exponential growth of COVID-19 cases in England. The second study describes reduced COVID-19 vaccine and antibody efficacy against the more transmissible variant. The first study, published today on the Imperial College London preprint server, involved testing a random sample of people from across England for COVID-19 as part of the ongoing Real-Time Assessment of Community Transmission (React 1) study. The researchers showed that COVID-19 infections in England surged from May 20 to Jun 7, with a doubling time of 11 days and an estimated R (reproductive) number of 1.44. Doubling time is the number of days before coronavirus cases, hospitalizations, or deaths doubled, and R indicates how many people, on average, catch the virus from an infected person.