Marin and UCSF differ on whether isolated Bolinas can be declared free of coronavirus

An egret searches for breakfast on a foggy morning at Bolinas Lagoon Nature Preserve.
(Allen J. Schaben / Los Angeles Times)

No one in the reclusive seaside town of Bolinas tested positive for the coronavirus during an unusual privately funded project, Marin County health officials said Wednesday.

Several hours after that announcement, however, officials from UC San Francisco Medical Center disputed that the testing results were final. “No conclusions can be drawn about actual rates of COVID-19 infection in the community until analysis of all samples is complete,” a UCSF spokesman said.

A group of volunteers raised private money to have the entire town, including people who work in Bolinas but live outside the community, tested last week. More than 1,800 Bolinas residents and area first responders were swabbed for the virus over four days. UCSF Medical Center is processing the samples.

The tests were performed inside tents in the parking lot of a neighborhood park. Community organizers attributed the lack of positive results to the Bay Area’s shelter-in-place orders issued several weeks ago.

A sign warns visitors away from Bolinas, Calif.
On Monday, a sign hangs outside of Bolinas, warning visitors away from the Northern California coastal community.
(Maura Dolan / Los Angeles Times)

It took about a month to organize the tests. Volunteers went to a dozen small stores in Marin County, gathering protective suits from hardware stores, gloves from restaurant suppliers, and masks from friends who had ordered them from China.

“We tested pretty much the entire population of Bolinas with [genetic] PCR and antibody tests for about $360,000,” said Jyri Engestrom, 42, a venture capitalist who has a home in Bolinas, population 1,680, and who helped organize the project. That $360,000 figure, he said, is close to what it costs to treat a single ICU patient.

Results for the antibody tests are expected next month.

Bolinas residents partnered with UC San Francisco infectious disease researchers to provide the tests to the remote town and a portion of San Francisco’s dense Mission District, which had a large outbreak of the disease.

The study of the highly disparate places will provide data about community spread of COVID-19, a UCSF news release said.

“All our public health decisions, including when it will be possible to relax regional and statewide shelter-in-place orders, are driven by rough assumptions about how this virus behaves based on very limited data,” said Dr. Bryan Greenhouse, an associate professor of medicine at UCSF.

The latest maps and charts on the spread of COVID-19 in California.

“Studying in detail how the virus has spread in these two distinctive communities will give us crucial data points that we can extrapolate to better predict how to control the virus in similar communities nationwide.”


Bolinas organizers said the town had a large population of older residents, who are at high risk.

It was not immediately clear why Marin County announced testing results that were later deemed preliminary by UCSF.