July 28 (Reuters) – Twitter Inc (TWTR.N) is shutting its reopened offices in United States, while other big tech companies are making vaccination mandatory for on-campus employees, as the highly infectious Delta COVID-19 variant drives a resurgence in cases.

Alphabet Inc’s (GOOGL.O) Google and Facebook Inc (FB.O) said on Wednesday all U.S. employees must get vaccinated to step into offices. Google is also planning to expand its vaccination drive to other regions in the coming months.

Twitter, which on Wednesday also paused future office reopenings, had started allowing employees back to its campuses in San Francisco and New York at 50% capacity about a fortnight ago after more than 16 months. read more

U.S. coronavirus cases have been rising due to the Delta variant, which emerged in India but has quickly spread and now accounts for more than 80% of U.S. coronavirus cases.

Health authorities on Tuesday said Americans fully vaccinated against COVID-19 should go back to wearing masks in indoor public places in regions where the coronavirus is spreading rapidly. read more

San Francisco-based ride-hailing company Lyft Inc (LYFT.O), which had already made vaccinations mandatory for employees returning to the office, postponed its reopening to February from September.

“We anticipate the COVID situation will remain fluid for the upcoming months, making it difficult for us to land a clear return date without a possibility of moving it again,” Lyft CEO Logan Green said in a memo to staff.

According to a Deadline report, streaming giant Netflix Inc (NFLX.O) has also implemented a policy mandating vaccinations for the cast and crew on all its U.S productions.

Apple Inc (AAPL.O) plans to restore its mask requirement policy at most of its U.S. retail stores, both for customers and staff, even if they are vaccinated, Bloomberg News reported.

Apple and Netflix did not immediately respond to requests for comments.

Many tech companies including Microsoft Corp (MSFT.O) and Uber (UBER.N) have said they expect employees to return to offices, months after pandemic-induced lockdowns forced them to shift to working from home.

Google also said on Wednesday it would extend its work-from-home policy through Oct. 18 due to a recent rise in cases caused by the Delta variant across different regions.

Reporting by Tiyashi Datta, Anirudh Saligrama and Ismail Shakil in Bengaluru and Sheila Dang in Dallas; Editing by Maju Samuel and Devika Syamnath

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