UCSF Study: San Francisco's Low-Income Latinx Essential Workers Still At High Risk For COVID-19 Infections
SAN FRANCISCO (CBS SF) -- During a 6-day COVID-19 testing effort at BART's 24th Street station, nestled in the heart of San Francisco's Mission District, UC San Francisco medical teams discovered that the city's low-income Latinx essential workers continue to be at great risk to contracting the illness.
The testing effort was led by Unidos En Salud, a collaboration between UC San Francisco and the Latino Task Force on COVID-19.
In an April Mission District study, Unidos En Salud identified the outsized exposure risk facing Latinx essential workers and their families driven in part by inequalities in economic and housing security.
The new August study revealed continued, unmet demand for access to testing.
"Seven months into this pandemic, low-income Latinx essential workers living in close-knit family units continue to be uniquely vulnerable," said Unidos en Salud Co-Founder Dr. Diane Havlir, who is also chief of the UCSF Division of HIV, Infectious Diseases and Global Medicine at Zuckerberg San Francisco General Hospital and Trauma Center.
The August initiative tested 2,622 people at the 24th St. Mission BART Plaza in six half-day sessions — at an average rate of 100 tests per hour.
Overall, 9 percent of the PCR swab-based tests came back positive for COVID-19 infection, with a test positivity rate of 11 percent among Latinx participants -- well above San Francisco's overall rate of 2.61 percent.
People from across the San Francisco Bay Area were tested at the plaza, but most positive results were seen in residents of the Mission or Southeast San Francisco.
Analysis of the amount of virus being shed by individuals who tested positive — conducted by collaborators at the Chan Zuckerberg Biohub — showed that about half had the high levels of virus indicative of the most infectious stage of the disease.
However, virtually all reported regularly wearing a mask when in public and using hand sanitizer.
Project leaders emphasize that the test results do not reflect a representative sample of Mission residents or public transit riders in general. Because the study was open to all, it likely over-counts individuals who wanted to get tested because they thought they might be sick.
To reduce barriers to testing, the new initiative provided free testing to all comers, with no requirement for preregistration, identification, or insurance.
The location at the central 24th Mission BART plaza — a hub for Bay Area Rapid Transit District trains and San Francisco Muni buses — made testing easily accessible to commuting workers as well as to local merchants and transit employees.
Those who tested positive were connected with resources to support isolation by community-based care teams.
"We show that low-barrier testing at a central transit hub is a highly effective way to reach essential workers and other vulnerable groups," Havlir said. "Our data also further demonstrate the need to provide infected individuals with rapid results and social support so they can go into isolation to avoid infecting their families and other contacts."
The results also highlight an urgent need to reduce delays between initial infection, testing, and isolation if public health efforts are to stem the continued spread within San Francisco of COVID-19.
Interviews with those tested at 24th St. Mission Plaza found that it took an average of five days from first symptoms until people who tested positive were able to go into isolation.
"Public health advice is to go into isolation for 10 days following the first symptoms, but if it takes almost a week from the time of infection to go into isolation, most of the harm has already been done," said Dr. Carina Marquez, assistant professor in the UCSF Division of HIV, Infectious Diseases, and Global Medicine.
Less than one-quarter of people who tested positive (22 percent) reported having access to any type of formal sick leave, and many asked to be referred to San Francisco's Right to Recover program to receive financial support for taking time from work and going into isolation. The city estimates the funds will not be available until mid-September.
"We hear from people all the time who don't have the privilege to take time off to get tested when they first notice symptoms, or aren't able to take time off work or make rent in order to go into isolation," added Jon Jacobo, chair of the health committee for the Latino Task Force. "As a result, this virus is still spreading rapidly through our community. It's outrageous that we're still experiencing this level of neglect seven months into the pandemic. We need direct and meaningful action, and we need it now."