Facebook and Google have asked their San Francisco Bay area employees to work from home as the coronavirus outbreak widens and worsens. Anthony Harrison, Facebook spokesperson, told Reuters that the company is “strongly recommending that all Bay area employees and contingent staff work from home starting Friday,” based on official advice. That includes the social media giant’s Menlo Park headquarters—though safety and security staff will continue to work on site. The Facebook spokesperson didn’t say whether or not there were any confirmed coronavirus cases in the HQ. Separately, Google has also offered a work-from-home option to employees in Bay Area offices, and Microsoft confirmed early on Friday that two of its employees have been diagnosed with the potentially deadly COVID-19 disease.