SAN FRANCISCO (KPIX) — Health officials across the country worried recent anti-police brutality protests will lead to a spike in the number of COVID-19 cases.

In San Francisco, the city set up a popup testing site at the Saint Mary’s Cathedral parking lot Cathedral Hill. The testing is free but people must make an appointment online at

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San Francisco health officials said people who have attended a protest or who plan to attend one should get tested.

UCSF epidemiologist George Rutherford said it’s hard to prevent virus transmission when thousands of demonstrators are gathered in tight spaces.

“To the extend that you’re yelling, you’re shouting, if you’re infected, you may be putting more viral particles in to the air. And then the final thing is tear-gassing and pepper spray which, thankfully, haven’t been used extensively here. People cough, they tear up… you’ll touch your eyes,” Dr. Rutherford said.

At a rally and march in San Francisco’s Mission District Saturday afternoon, all the demonstrators wore masks but they admitted it was impossible to stay six feet apart from others.

“I think it is a danger,” said protester Bruce Neuburger. “Here’s a moment where we can change things so is it worth the risk? And I say yes, it’s worth the risk.”

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San Francisco health officials encourage protesters to get tested even if they don’t show any symptoms of infection.

A volunteer at the testing site said a few hundred people had already signed up for appointments this weekend.

“This terrible disease is disproportionately affecting people of color,” said Affan Khokhar, who attended recent protests and received the test on Saturday. “It feels contradictory to do the protest and also not be tested.”

None of the people KPIX 5 interviewed said they felt any symptoms but they want to have a peace of mind.

“It’s all about keeping people safe, keeping your friends safe, and keeping the community alive,” Khokhar said.

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Most people are able to get an appointment by the following day.