Though California has reached 800,000 tested cases of coronavirus we have relatively low deaths per capita compared to most other states

This is because if you are in the coastal regions in big cities or suburbs most people almost always are wearing masks. All stores require people to wear masks and so compared to other states this is somewhat unusual in other states too. My son was telling me his company in Oregon is only just now insisting people who come into his company always wear masks or will be asked to leave. So, this is a kind of hit or miss thing in many states but not in the bigger cities in California like San Diego, Los Angeles cities, and San Francisco and Sacramento. However, even in California if you go out into the country often only about 1/2 of the people are wearing masks. My son visited me in Mt. Shasta around 4th of July from Oregon where he lives and walked into a Subway Sandwich store in Mt. Shasta and literally NO ONE was wearing a mask so he just walked out again without buying a sandwich once he saw this. Of course he has a Bachelor of Science degree in Nursing and completely understands how insane it was in that Subway as crowded as it was with people, none of whom were wearing masks but him. 

The problem is statistical here:

An average of 1 in 15 people is infected in any given situation. Therefore if you are in a crowd of more than 10 people it gets risky being indoors with them, especially if they aren't wearing a mask simply because most people who are infected don't even know they are infected, especially if they are asymptomatic. (This just means they have no symptoms but are carriers).

So, someone like this would have a normal temperature and not have  cold or flu symptoms and not have any trouble breathing but still carrying the disease potentially to other people everywhere they go.