That can certainly skew the numbers, and that's something Dr. Cameron Kaiser said they wanted to avoid with this survey.
"We tried to make sure this was as random a sample as possible, so we hired a public relations firm to go through addresses to pick an even mix of population, geographics, and then we reached out to those people instead of them reaching out to us," he said.
Of about 3,500 people contacted, 1,726 people were tested, and 101 tested positive, which is a positivity rate of 5.9 percent.
Kaiser says that means somewhere between 118,000 and 175,000 people have already had the virus, which might give us a better idea of the true fatality rate.
"We haven't finished the data analysis, but I will say most estimates place it somewhere between 0.5 and 1 percent overall, and I'm not seeing anything with our numbers that challenges that," he said.
That would make COVID-19 five to 10 times deadlier than the flu.
Kaiser says there are things this survey does not tell us.
"Doesn't tell us if these people are immune, we don't know how good those antibodies are. We don't know how long they'll last, I would certainly hope they're immune because it would tell us the vaccine candidates out there are on the right track, but it's not proven yet," he said.
But just running the numbers, if about 6 percent of county residents have already had COVID-19, that means about 94 percent of them have not.
Kaiser stressed, "The vast majority of people in Riverside County have yet to have COVID-19, and that means if herd immunity even exists for COVID-19, which is by no means certain, we're nowhere near it."
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