The virus mutates rapidly. It is a given that the virus is being carried across the border, so it doesn’t take a rocket scientist to figure out why it’s spreading in CA. Also, most clinics do not have test kits. They are treating symptoms. The number of covid-19 positives is higher than what is being reported.
In Oregon it was announced on news today that 176 people being “monitored”...76 released ( I think that’s what I heard)...FWIW