By CBS13 Staff

SACRAMENTO (CBS13) — Clinics scheduled to take place through Sacramento County’s Equivax collaboration are automatically switching people from the Johnson & Johnson to the Pfizer COVID-19 vaccine, officials say.

On Tuesday, the CDC and FDA released a joint statement recommending a pause in the use of the Johnson & Johnson vaccine.

The agencies said they are reviewing six reported cases of a “rare and severe” type of blood clot in people who have received the J&J single-dose vaccine. This comes after more than 6.8 million doses of the J&J vaccine have been given out.

Health officials said all the blood clot cases they are looking into happened to women between the ages of 18 and 48 and occurred 6 to 13 days after getting the vaccine.

California was already bracing for a sharp cut in the supply of the Johnson & Johnson vaccine.

Due to the guidance from the CDC and FDA released on Tuesday, Equivax announced their scheduled clinics will be using only the Pfizer and Moderna vaccines.

Gov. Gavin Newsom also announced on Tuesday that California will be following the guidance and temporarily pausing its use of the Johnson & Johnson vaccine. 

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“Vaccines are still overwhelmingly safe,” Newsom tweeted. 

Newsom noted that the Johnson & Johnson vaccine accounted for just 4 percent of California’s supply. 

People with appointments scheduled at Equivax locations, like Tuesday’s event at Luther Burbank High School, don’t need to do anything as appointments have automatically been switched to the Pfizer vaccine.

The limited supply also means that Equivax clinics will not be able to take walk-ins on Tuesday, officials said.

About 4,000 doses of the Johnson & Johnson vaccine were scheduled to be administered at the Luther Burbank event on Tuesday.

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Sacramento’s Loaves & Fishes has also canceled its weekly vaccination clinic for homeless people as the vaccine that would have been administered is the Johnson & Johnson one.