“Don’t know much about Santa Clara County. . . “
It is the home of Silicon Valley and because the valley and county favored developing office space over living space, its workers come from throughout the Bay Area and into the Central Valley. Thousands, tens of thousands of workers, commute to and from there every day. There are homeless and it is heavily settled by Asians and travel to Asia is very common, but whatever pops there probably will pop all around the central part of California immediately afterwards unless they shut it down.
Let me amend my comment. If it pops there among the computer industry workers, it will likely spread throughout the area. If this particular Victim #1 is isolated from the commuting public, the spread is probably not going to happen.
Santa Clara County is the US travel hub for tech, nationwide. And to Asia tech. And near the epicenter, if not THE epicenter of Chinese people in CA.
If it IS spreading there, it will spread everywhere very quickly unless completely shut down.