With new coronavirus clusters sprouting aboard ships overseas, the U.S. cruise industry is extending its suspension of operations through October.

The Cruise Lines International Association, which represents more than 50 companies and 95% of ocean-going cruise capacity, said Wednesday that if conditions in the U.S. change, it would consider allowing short, modified sailings.

A no-sail order for U.S. waters initially issued by the Centers for Disease Control in March has been extended through Sept. 30. The CLIA has extended its travel suspension twice.

A Norwegian cruise line halted all trips and apologized Monday after a coronavirus outbreak aboard one vessel infected at least 5 passengers and 36 crew. Health authorities fear the ship may have spread the virus to dozens of towns and villages along the west coast of Norway. The Hurtigruten cruise line was one of the first to resume sailing in June, offering cruises from Germany to Norway.

Positive coronavirus tests have also been reported this week on cruise ships in Italy and Tahiti.

The risk of infection aboard a cruise ship is elevated because of the close quarters. Between March and July, there were 2,973 reported cases of COVID-19 or COVID-like illnesses about ships in U.S. waters, according to the CDC. As of July 10, there were still 14,702 crew members aboard 67 ships.

Royal Caribbean Group and Norwegian Cruise Line, both based in Florida, are working together with a panel of health experts to develop plans for preventing and treating COVID-19 at sea. Details are expected later this month.

The industry has been devastated by the pandemic. Each day that ships remain inactive costs $110 million in economic activity, according to the CLIA. States that rely on the cruise industry, like Florida, Texas and Alaska, have been hit particularly hard.