Alright, time to bring a least one raw data point to this thread which has turned into speculation central with a paucity of data.
Everyone is speculating about what the level of herd immunity in the population is right now, with people saying "there are there tons of silent carriers" spreading things around, that are "we above 20% (or even 10%) of people that have been infected and recovered", etc. etc. etc. I even hear this ALL the time out of my neighbors. They say "oh, I had something that sounds EXACTLY like the milder version of COVID-19 back in January, so I think myself and my family are probably immune and we need to lift the SIP order."
Well, at least in San Diego county, that is FAR from true.
I spent 6.5 hours today at
COVID Clinic in San Diego. They were doing drive up antibody testing as well as swabs for PCRs. It was very easy to tell what tests were being performed because they put a different color placard on the windshield of every car in line (red was anti-body only testing).
Now, this is a self-selected group - these are people that THINK they had the symptoms of COVID-19, and are willing to pay $75 a pop to get tested (insurance accepted only for the PCR, not for the anti-body).
I got there about noon, and got tested about 6PM, my results came in about 10 minutes after that. I love people watching and did a LOT of that here (and Netflix - thank you Elon for putting that in the car).
When I got my results, I explained to the nurse I was a physician and was curious what their percent positive is looking like for the antibody test (FYI, they are doing both IgG and IgM on the test strip).
She told me that she doesn't have exact numbers to share, but that she had been there all day and the positive antibody results were well below 5% out of everyone that they had tested that day (today was the first day). They had done well over 1000 tests by the time I was tested.
It's anecdotal, I'm the first to admit that, but less than 5% out of a group that believes they had symptoms consistent with COVID-19 means that we are a LONG LONG LONG way from herd immunity.
Hunker down people, we are just at the beginning of this.