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.
Youth test positivity rate five times higher than seniors’
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.
In total, 135 of 108,911 swabs tested positive for COVID-19, for a weighted prevalence of 0.15%, up from 0.10% of swabs collected from Apr 15 to May 3. Northwest England had the highest prevalence (0.26%), while the country’s southwest region had the lowest (0.05%). Residents of socioeconomically disadvantaged areas were at nearly double the risk of testing positive, compared with those in less-deprived areas.