Why is the COVID case rate in San Francisco so much higher than the U.S. right now?

Why is the COVID case rate in San Francisco so much higher than the U.S. right now?

For almost the entire pandemic, San Francisco’s COVID-19 case rates have been lower than the nation’s as a whole. But not anymore. Earlier this spring, the city’s confirmed new case rates climbed above those of the U.S. Then, on May 3, San Francisco’s case rate doubled that of the U.S. As of May 10, the national daily case rate was at about 23 new cases per 100,000 people, whereas in S.F. the rate was at 42 per 100,000, according to data from the New York Times analyzed by The Chronicle. Peter Chin-Hong, an infectious disease expert at UCSF, said that San Francisco’s current high case rates are likely due to the city being relatively protected from the disease for the last two years, combined with city residents taking more risks …
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