Few if any residents of remote Bolinas have been infected with coronavirus, study finds

A beachgoer walks near the waves in Bolinas, Calif., in April.
(Maura Dolan / Los Angeles Times)

Few if any residents of the tiny Marin County hamlet of Bolinas have antibodies for COVID-19, researchers reported Thursday.

Residents of this isolated beach town, famously known for trying to keep out strangers, were tested in late April both for the coronavirus and its antibodies. Residents raised money for the tests, and UC San Francisco subsidized the project.

No one tested was found to have an active case of the disease, and the results of the antibody tests show that between zero and three in 1,000 people in Bolinas were previously infected, UCSF infectious disease researchers said.

“Our goal with this study was to understand how widely the novel coronavirus had spread in a relatively isolated community like Bolinas before or soon after the stay-home orders went into effect,” said Dr. Bryan Greenhouse, a professor at UCSF.


The results “suggest that few if any people in Bolinas had ever been infected by the virus as of the end of April,” he added.

Researchers analyzed 1,880 blood samples, using two different tests to look for antibodies, and combined results from the two tests to statistically estimate population-level infection rates.

“It is quite possible that no people in Bolinas were ever infected,” Greenhouse said in an interview.

He noted that all tests render some false positive findings, and the results had to be estimated.

“While the antibody tests we used are amongst the most accurate available, no test is perfect, and individual results should be taken with a grain of salt,” he said.

Among the rules for newly reopened facilities are a limit on capacity, stringent cleaning requirements and a mandate that staff wear face coverings at all times.

June 11, 2020


Researchers said the results show the effectiveness of stay-home orders, particularly for remote, rural places many miles away from highways, researchers said.

After the Bay Area issued stay-home orders in March, surfers arrived in Bolinas in droves. Residents posted themselves at the entrance of town to shout at drivers to turn around and go home.

The townspeople also made signs and posted them on roads leading into town. “Bolinas closed to visitors for duration of pandemic. Residents, deliveries only,” said one sign.

Bolinas historically has been unwelcome to visitors. Town leaders limited water hookups decades ago to deter development, and residents regularly tore down traffic signs that showed how to get to the beach community. Bolinas is surrounded by the sea on three sides and reachable from San Francisco only by a long, windy road.

Tech executives eventually moved in, and the newcomers came up with the idea to test everyone in town for the coronavirus. Bolinas has a high percentage of elderly residents, many who live below the poverty line, and the newcomers feared the virus might ravage them.