The new policy, applying to all employees and guests ages 2 and up, takes effect Friday, July 30.
"We are adapting our health and safety guidelines based on guidance from health and government officials, and will require Cast Members and Guests ages 2 and up, to wear face coverings in all indoor locations at Walt Disney World Resort and Disneyland Resort beginning Friday, July 30, regardless of vaccination status," park officials said in a media statement.
It comes after the CDC issued new guidance again recommending that everyone - vaccinated or not - wear masks while indoors in public settings. The state of California on Wednesday also made similar recommendations.
The CDC updated its guidance as the country faces a new spike in COVID-19 cases, primarily due to the highly-contagious delta variant.
Most of the new cases are among the unvaccinated, but health experts have noted that even those who have received the vaccine can carry and transmit the coronavirus. There are also breakthrough cases of vaccinated people developing COVID-19, but the symptoms are usually milder than among those who have not been vaccinated.
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Disneyland reopened in late April after being closed for more than a year during the pandemic. It initially had strict mask requirements in place but later loosened those for vaccinated guests after the state of California reopened businesses and lifted most social distancing and mask requirements on June 15.
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