Facebook on Thursday announced it is cancelling its annual developer conference because of the spread of the coronavirus.

“This was a tough call to make — F8 is an incredibly important event for Facebook and it’s one of our favorite ways to celebrate all of you from around the world — but we need to prioritize the health and safety of our developer partners, employees and everyone who helps put F8 on,” Konstantinos Papamiltiadis, director of platform partnerships at Facebook, wrote in a blog post announcing the cancellation.

“We explored other ways to keep the in-person part of F8, but it’s important to us to host an inclusive event and it didn’t feel right to have F8 without our international developers in attendance.”

The annual conference was scheduled for May 5 and 6 in San Jose, Calif.

The Centers for Disease Control and Prevention confirmed Wednesday the first U.S. coronavirus case of unknown origin in Northern California. On Thursday, California Gov. Gavin Newsom (D) said the state was monitoring over 8,400 people for the virus.