SAN FRANCISCO (CBS SF) – Health officials in San Francisco are warning residents about unauthorized COVID-19 testing sites, as demand for tests remains high amid the omicron surge.

“Unauthorized COVID-19 test sites are popping up throughout the City,” the city’s Department of Public Health tweeted Friday.

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The warning echoes similar complaints brought to the Better Business Bureau, according to Alma Galvan, a spokesperson for the organization.

“We’ve also heard of consumers, unfortunately, going to testing sites that have not been verified or confirmed by the California Department of Public Health,” Galvan told CBSN Bay Area.

The BBB said it has also received complaints about fraudulent websites claiming to offer testing kits, but do not actually have the products.

“Since COVID started, we’ve seen these schemes change drastically, it’s always when we’ve seen a huge spike in cases,” Galvan said.

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Additional details about the unauthorized San Francisco sites were not immediately available, but similar schemes have been reported in other parts of the country.

Last month, the attorney general in Maryland issued a consumer alert about unlicensed sites in the Baltimore area, saying they are taking personal information such as Social Security numbers, drivers’ license information, health insurance information, along with DNA. The sites were located outside stores, shopping centers and along the side of the road.

“Providing personal information, such as Social Security Numbers, to individuals hosting one of these pop-up sites not only puts your health at risk, but increases your chances of becoming a victim of identity theft,” Maryland Attorney General Brian Frosh said at the time.

Unauthorized COVID-19 testing sites have also been reported in other cities, including Chicago and St. Louis. In Illinois, Attorney General Kwame Raoul warned consumers to watch for certain red flags, including sites that are charging out of pocket costs and staffers who are unmasked or not wearing appropriate PPE.

The warning comes as the Bay Area and California is seeing a surge in cases due to the omicron variant. As of Friday, the state’s 7-day test positivity rate was at 21.8 percent, according to the California Department of Public Health.

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SFDPH urged residents to use FDA-approved rapid test kits, to get tested through their healthcare provider or through other authorized sites. Information about authorized COVID-19 testing sites can be found by visiting sf.gov/gettested.