The new rules announced by the county health department Tuesday are a response to the growing threat of the Delta variant, which has led to a recent increase in COVID-19 cases and hospitalizations.
Under the order, routine testing will be required of all athletes and staff participating in moderate or high-risk sports, regardless of vaccination status. Those include football, basketball, baseball, cheerleading, tennis and soccer, among others.
At a minimum, the county is requiring weekly testing. But testing two times a week is "strongly recommended for unvaccinated participants and staff."
In addition, testing should be done 48 hours before any inter-team competition, with results made available before the event begins.
Athletes, students, coaches and spectators involved in indoor sports must wear masks and can take them off only to eat or drink.
Athletes in water sports such as swimming or water polo can remove their masks while in the water.
Athletes are advised to bring more than one mask in case they get dirty or wet during play.
Health officials are also urging schools to install air filtration systems in buildings where sporting events are held.
"Given the increase in community transmission of COVID-19 and the predominance of the more easily spread Delta variant of the COVID-19 virus, masking indoors, regardless of vaccination status, is essential to slowing the spread of COVID-19 in the community," according to the county's guidance.
"The Delta variant of the COVID-19 virus spreads more easily than strains of the virus that circulated in L.A. in the past."
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