The county previously only recommended mask-wearing indoors. The new mandate will take effect at 11:59 p.m. Saturday, officials announced.
The announcement was made during a virtual briefing on Thursday afternoon. It comes exactly one month after California dropped its statewide mask mandate for vaccinated people.
Some exceptions will apply, health officials said, similar to masking requirements that were in place before June 15. Additional details about those exemptions were not immediately disclosed.
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L.A. County Health Officer, Dr. Muntu Davis, said the new health order will be published at covid19.lacounty.gov no later than Friday.
Davis said the county is "not where we need to be" in terms of vaccinations against the virus, as evidenced by seven straight days of new cases numbers that topped 1,000. On Thursday, the county reported 1,537 new infections, the highest number since early March.
Asked what additional restrictions health officials might take if the rise in COVID-19 cases worsens, Davis said: "Everything is on the table."
Meanwhile, the city of Long Beach will follow suit and reinstate its own mask mandate for everyone, also regardless of vaccination status.
This comes as the city reported a nearly 300% increase in COVID-19 cases in the last two weeks. In Pasadena, masks are just being recommended indoors for now. Both cities have their own health departments.
Nationwide, the daily case average is up more than 65% in the last week and has *doubled* in the last three weeks.
There are some breakthrough cases in those that have been vaccinated, but those are relatively rare and result in symptoms that are less severe.
Misinformation about vaccines is being blamed for some people still being hesitant to get vaccinated.
U.S. Surgeon General Dr. Vivek Murthy called the falsehoods an urgent threat to public health.
"We are not out of the woods yet," Murthy said. "Millions of Americans are still not protected against COVID-19. We are seeing more infections among those who are unvaccinated."
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