California town offering coronavirus testing to every resident

Residents in San Francisco's Mission District will also be tested as part of the study

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An entire Californa town will be tested for COVID-19, one of the first communities to do so since the outbreak of the coronavirus reached the U.S.

Researchers at the University of California, San Francisco are testing residents of Bolinas, a rural town in western Marin County, for the virus as well as the presence of antibodies. The testing for antibodies would reveal if a person has already been exposed to the virus, as part of a study to better understand how the virus spreads, according to the university.


The researchers have partnered with community organizations to provide the free, comprehensive and voluntary COVID-19 testing effort to nearly 2,000 residents over a four-day period.

"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 and one of the researchers involved with the study. “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.”

Beginning April 25, researchers will also begin testing roughly 5,700 residents in San Francisco's Mission District over the course of four days.

Researchers are using nasal swabs to test residents to see if they are infected with COVID-19. To test if those have already been exposed to the virus, researchers are using finger-prick blood samples, which they say can reveal past exposure in both children and adults.


"Because diagnostic tests cannot detect the presence of the virus once it is cleared from the body (which can happen whether a person was asymptomatic or recovered on their own), both types of test are essential to understanding how widely the disease has already spread in these communities," the university said.

Those who test positive for COVID-19 will get immediate follow-up calls from the university's infectious disease experts who will assist in isolating the individual as well as connecting them with medical support.

Even if participants test negative, they are expected to continue to follow shelter-in-place and social-distancing guidelines to help curb the spread of the virus. Researchers cautioned that there is a possibility of false-negative test results.

“This study stands to benefit people at three levels – individuals who will get to learn their disease status, the community for the opportunity to isolate and eradicate the virus, and worldwide through improved ability to understand how this virus spreads,” said Dr. Aenor Sawyer, a Bolinas resident and UCSF orthopedic surgeon serving as project medical director and liaison between the community and researchers.

The hope is that this effort will provide a model for other communities.