As the United States warns of an emerging coronavirus outbreak, the gaming industry's biggest gatherings have all be impacted. The upcoming Game Developers Conference (GDC) has been hit particularly hard and changed many gaming giants' trade show plans.

In late February, Epic Games and Unreal Engine announced first on Twitter (TWTR  ) that they would be pulling out of GDC. On the same day, Microsoft (MSFT  ) also announced that it would be withdrawing from the event.

The following day, Blizzard Entertainment and Amazon (AMZN  ) also announced on Twitter that they would not be attending GDC, citing "growing concerns" around coronavirus. Facebook's (FB  ) Oculus virtual reality subsidiary also pulled out of GDC. The company advised all employees to refrain from travel.

Thus far, over 10 companies, also including Sony (SNE  ), have announced that they would not send employees to the show over concerns about the spread of coronavirus.

Because of these withdraws, GDC 2020 organizers announced on Monday that the event, which was scheduled for March 16-20, will be cancelled and told vendors and attendees to wait for further confirmation of a future date. In a statement, GDC organizers said that "we fully intend to host a GDC event later in the summer."

The team running GDC believes it can still run a safe and successful event, noting the departments of health at the state and city level support the convening of public events. GDC also said that the official event site, i.e. San Francisco's Moscone Center, will undergo more stringent cleansing and disinfecting practices.

GDC in San Francisco was expected to draw tens of thousands of game developers from around the world, including Asia. Last year's attendance was 29,000.

However, the spreading coronavirus isn't necessarily bad news for all video game companies and stocks. Though there could be hits to gaming companies' supply chains, gaming firms in China have already seen a notable spike in active users, something U.S. firms could also see if schools and offices close for extended times in the near future.