Michael Worobey, a biologist at the University of Arizona, has seen more than 100,000 different strains of the virus that causes Covid-19. But when he saw the new variant from the UK, he noticed something different.

“This is the first variant I’ve seen during the whole pandemic where I took a step back and said: ‘Whoa,’ ” he remembers…

Bedford said he doesn’t believe the vaccine will be useless against the new UK strain, but that it might lower its effectiveness somewhat.

“It might decrease vaccine efficacy from 95% to something like 80% or 85%,” he said. “It would be a modest effect, not a dramatic effect.”