LONDON, June 2 — Britain is in talks with Oxford and AstraZeneca for additional doses of their Covid-19 vaccine that has been changed to better target the “beta” coronavirus variant first identified in South Africa, health minister Matt Hancock said today.

“We’ve started commercial negotiations with AstraZeneca to secure a variant vaccine: future supplies of the Oxford AstraZeneca vaccine that have been adapted to tackle the B.1.351 variant first identified in South Africa,” Hancock said in a speech at Oxford University. — Reuters