Public health officials are worried about the Delta variant of the COVID-19 coronavirus, but two U.K. studies published Monday found that two doses of leading vaccines offer "very, very substantial" protection against the new, highly transmissible strain, Aziz Sheikh, director of the University of Edinburgh's Usher Institute and lead author of one of the two studies, tells The Wall Street Journal.
One analysis by Public Health England of more than 14,000 Delta infections found that two doses of the Pfizer/BioNTech vaccine reduced the risk of hospitalization by 96 percent, while a double dose of the Oxford-AstraZeneca vaccine lowered the risk by 92 percent. The second study, published as a letter in The Lancet by academics and public health experts in Scotland, found that two doses of either vaccine reduced hospitalization from the Delta variant by 70 percent and offered robust but slightly diminished protection against infection.
The Delta variant, first seen in India, is now the dominant strain in Britain, accounting for 90 percent of new cases. Compared with previous variants, the Delta mutation appears significantly more likely to infect people who have only received one dose of the two-shot vaccines. The U.K.'s initial vaccination strategy involved getting one jab into as many arms as possible before focusing on second doses. "We've got an opportunity to counter the threat of this Delta variant by encouraging uptake of both doses of the vaccine," Jim McMenamin, national incident director for COVID-19 at Public Health Scotland, told reporters Monday.