By Gwendolyn Wu

With the latest subvariants driving the sixth wave of infections into summer, it’s not impossible, doctors say. In fact, it’s perhaps more common to catch the virus from someone who is asymptomatic than previously thought.

Doctors guess the likelihood is close to 1 in 20.

“It’s been a very useful measure of something that otherwise is very hard to get your arms around, which is the probability that somebody standing next to you in line at a Safeway in the Bay Area would test positive for COVID if I could test them now,” said Dr. Bob Wachter, a UCSF infectious diseases expert.