SANTA ROSA (CBS SF) – Sonoma County will start testing some people for antibodies produced in response to the coronavirus, county officials said Thursday.

Beginning Saturday, first responders, people who have recovered from the virus and people who have come in close contact with them can be tested at the public health lab in Santa Rosa.

Testing will be done daily. County officials said the plan is to expand the testing to health centers and some hospitals in the county.

The testing is an effort to better understand how the virus spreads. County health officials reported on Thursday that four people in the county have died from the coronavirus and 593 people have been infected.

The testing plan calls for 110 people to be tested per day and as more testing sites begin operating, the aim is to have tested 3,500 people by first week of July. Testing is not available for members of the public.

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