Concerns over the COVID-19 pandemic are now affecting major events set in June, as the giant influencer gathering VidCon cancelled its annual gathering in Anaheim, Calif., with hopes to create a replacement U.S. event “in the fall.”

This year’s VidCon would have been the 11th, and the third since the company was bought by ViacomCBS from the Green brothers, Hank and John, who are themselves prominent influencers (and John a hugely successful novelist behind The Fault in Our Stars and other young-adult books).

“We were so excited about the 11th annual VidCon US, but our number one priority is always the safety and health of our attendees, sponsors, speakers, creators, and staff,” said VidCon General Manager Jim Louderback in a statement released this morning.

“Unfortunately, due to the continued uncertainty surrounding COVID-19, and the precautions being taken by authorities worldwide to manage this pandemic, we have come to the difficult decision to cancel VidCon this June," Louderback continued. "We are working hard to bring you a VidCon US experience this fall and will keep you posted as those details come together. Don’t worry; it will still be an amazing event that you won’t want to miss!"

From modest beginnings in a hotel's basement ballroom in Los Angeles, VidCon's main event has flowered into the biggest gathering on the calendar for social-media platforms, star influencers and thousands of fans.

In turn, that's attracted dozens of big brands and major media companies trying to reach those increasingly elusive young audiences. YouTube has been the biggest sponsor of the event since its second year. The ViacomCBS acquisition only ramped up further involvement by its networks such as Nickelodeon, MTV and Comedy Central, which together sent hundreds of employees to last year's gathering.

The organization said it will refund by April 15 any ticket and merchandise purchases for the show, which was scheduled for June 17 to June 20 at the Anaheim Convention Center. For those who previously had cancelled their tickets because of COVID-19 concerns, the organization will refund any processing fees applied when the tickets were cancelled. The company will send out receipts detailing the refund transactions, and also will send a second follow-up email for those who booked hotel rooms or bought tickets to the event’s Disney Day held at Disneyland across from the Convention Center.

California is among the states grappling most aggressively with the COVID-19 pandemic and its impacts, with “shelter-at-home” restrictions on most of its 40 million residents, increasingly extensive shutdowns of most businesses and now public spaces, among other efforts to control the coronavirus.

VidCon has routinely attracted 35,000 or more visitors from around the United States and beyond for its mothership gathering.

It also has been branching out with international versions of the conference in Australia, Asia and Europe. The release said the company plans to have an announcement about a fall event by June 15.