Royal Caribbean's new megaship, Odyssey of the Seas, was supposed to hail the company's return to business as near-usual this summer. But the ship's launch is now delayed after eight crew members tested positive for the coronavirus. Its first scheduled trips are now canceled.The Odyssey of the Seas had been slated to make its debut sail with paying passengers on July 3 — more than a year after the pandemic hobbled the cruise ship industry. Its first voyage is now delayed for four weeks, until July 31. By then, summer will be nearly halfway over."While disappointing, this is the right decision for the health and well-being of our crew and guests," Royal Caribbean CEO Michael Bayley said as he announced the delay.The cruise line said it's contacting customers to discuss refunding tickets and rebooking their trips.All 1,400 crew members aboard the ship will now be quarantined. The entire crew had been vaccinated on June 4, the same day the ship arrived in Port Canaveral, Fla., Bayley said. The positive cases sprang up before their vaccinations could be considered fully effective.Crew members of the Odyssey of the Seas were tested on the day they arrived in Florida. A week later, a second round of tests returned the positive results. The Centers for Disease Control and Prevention requires regular tests in the conditional sailing order that has allowed the U.S. cruise industry to restart operations.The cruise company said medical staff is monitoring its infected crew members. Six of them are asymptomatic, and two have mild symptoms, Bayley said.Cruise ships were banned from operating from U.S. ports in March 2020 when the CDC issued a no sail order due to the pandemic. Cruise trips were linked to early COVID-19 outbreaks in the U.S., and outbreaks of cases on ships have been blamed for at least 41 deaths.The first commercial cruise to launch from a U.S. port in more than a year is expected to take place in 10 days when a Celebrity Cruises ship will depart from Fort Lauderdale, Fla., for a weeklong tour of the Caribbean.Under the CDC's new guidelines, cruise ships will be able to operate under near-normal conditions if a large portion of passengers and crew are fully vaccinated. Guests who are vaccinated against the coronavirus can even fill up their own plates at the buffet, for instance. Copyright 2021 NPR. To see more, visit https://www.npr.org.