Sun Country Airlines is trimming flights starting in April as ticket sales slip over coronavirus fears.

The Twin Cities-based carrier is reducing flight frequencies from Minneapolis-St. Paul International Airport to 14 airports, including several on the West Coast where the heaviest concentration of COVID-19 cases in the U.S. has been reported.

Sun Country is also suspending three Portland, Ore., routes — to and from Honolulu, Las Vegas and San Francisco — for the entire summer.

The ultralow-cost airline, headquartered at MSP, said Thursday it wasn't seeing any changes in demand this month, which includes its busiest travel holiday, Minnesota spring break.

But by early evening Thursday, Sun Country notified its employees of flight cuts beginning in April and running through the summer.

"Travel demand is being impacted by the uncertainty around COVID-19, and we're seeing softness in bookings for April and May. In response, we've made targeted capacity adjustments," a Sun Country spokeswoman said in an e-mail. "Most of the reductions are in markets where we offer many flights, allowing seamless reaccommodation opportunities for customers."

Beginning in April, Sun Country will operate fewer flights between MSP and Los Angeles, Seattle, San Francisco, San Diego, Phoenix, Chicago-O'Hare, and Mazatlán and Puerto Vallarta, Mexico. In May, Sun Country's flight capacity from MSP to Anchorage, Alaska, Boston, Dallas-Fort Worth, Las Vegas, Newark, N.J., and Fort Myers, Fla., will also decrease.

The airline in May also plans an early exit from its seasonal route between MSP and Punta Cana, Dominican Republic. Service levels will return to normal in June, with Anchorage sustaining reduced service to and from the Twin Cities for the remainder of the summer.

"Our hope is this will be the extent of our schedule changes, but this is a unique situation, so we will continue to closely monitor demand for necessary adjustments," the spokeswoman said.

The news comes a day after an airline trade group released a grim forecast, estimating that the outbreak could cause more damage to the industry than the Great Recession or 9/11.

The International Air Transport Association said the plunge in air travel — both for business and leisure — could amount to $113 billion in lost revenue for the world's airlines, about one-fifth of their annual total.

That's on par with the effect of the 2008-2009 recession and worse than the SARS outbreak in 2003.