Infected but not feeling it

Some of the cases were asymptomatic, most involved mild to moderate symptoms and only two required hospitalization, officials said. The infections were determined to be Delta-related because most samples in San Francisco were tested for the variant, which is now dominant in the city.

“We’re concerned right now that we’re on the rise of a surge here in San Francisco and the Bay Area,” Dr. Day said. “But what we’re seeing is very much what the data from the vaccines showed us: You can still get Covid, potentially. But if you do get it, it’s not severe at all.”