Survey of blood samples suggests between 2.49% and 4.16% of county residents may have coronavirus antibodies.
The number of coronavirus infections in Santa Clara County could be between 50 and 80 times higher than the officially confirmed count, preliminary results from a community-based study by a team of Stanford University researchers indicates.
The prevalence study, led by Stanford Assistant Professor Eran Bendavid, has not been formally published and is still undergoing peer reviews. It has, however, been published on the preprint server medRxiv. As such, it is effectively a first draft, subject to change based on input before formal publication.
That said, the early findings indicate that between 48,000 and 81,000 residents in Santa Clara County were infected as of April 1, back when the official count was 956. The estimate is based on 3,330 blood samples that were taken from volunteers in Mountain View, Los Gatos and San Jose on April 3 and April 4 and tested for antibodies to SARS-CoV-2 .
When adjusted for Santa Clara County’s population and demographics, the number of positive results suggests that between 2.49% and 4.16% of the county’s 1.93 million residents have had COVID-19…
To read the entire article from Palo Alto Online, click https://paloaltoonline.com/news/2020/04/17/stanford-study-more-than-48000-santa-clara-county-residents-have-likely-been-infected-by-coronavirus
CORONAVIRUS WATCH ANALYSIS: This is the closest thing we’ve seen in the U.S. yet to a random sample of the population being tested for antibodies indicating they had Covid-19. It’s not a true random sample, as participants were volunteers recruited from a Facebook ad and asked to drive to a testing center, so it might have had any of several unintended bias — for example, it underrepresents people without cars, people who felt sick in March might have wanted to volunteer and thus might be overrepresented in the sample, and people who felt very sick on the testing dates might be underrepresented in the sample. But the results seem in the ballpark of reasonability…
