United Airlines on Thursday said it will scale back its flights to Barcelona after the Mobile World Congress — the world's largest telecommunications trade show — was canceled because of the virus. The annual event, which was scheduled for later this month, drew some 100,000 people last year.

The carrier had built up service for the event, adding two nonstops and using larger aircraft. It's part of a trend among airlines to chase customers willing to pay high prices for special conferences such as the Consumer Electronics Show in Las Vegas, political events and sports, with additional, targeted service.

United said it would provide a full refund to travelers who don't want to travel to Barcelona because the event was canceled and that it will waive cancellation fees.

United had added four round-trips between San Francisco and Barcelona for the event, and it will cancel two of them — leaving on Feb. 26 and Feb. 27 — and use smaller aircraft for the others. It will also use smaller planes on routes from San Francisco and Newark to Barcelona than it had previously planned.