Just as cruises resume after more than a year on pause, the industry is facing an immediate setback.
Two passengers sharing a stateroom aboard the Celebrity Millennium, operated by Royal Caribbean’s Celebrity Cruises from the Caribbean island of St. Maarten, tested positive for the coronavirus on Thursday. The ship, billed as the first fully-vaccinated cruise in North America, has one more day at sea on Friday before returning to St. Maarten to disembark.
All guests will take an antigen test as part of their disembarkation process, said Susan Lomax, the company’s associate vice president for global public relations.
In a statement, the cruise line said that the passengers tested positive during required testing before leaving the ship. The travelers are asymptomatic and are in isolation under observation by a medical team. Testing and contact tracing is in place for close contacts.
The ship’s 650 crew members and 600 or so passengers (including a New York Times reporter) were required to be vaccinated before boarding, and had to show proof of a negative coronavirus test taken within 72 hours before sailing from St. Maarten last Saturday.
Two passengers on a Mediterranean cruise operated by MSC Cruises also tested positive. Both passengers on the MSC Seaside were asymptomatic when they tested positive during routine testing two days ago, the communications manager Paige Rosenthal said. Immediately after testing positive, the two passengers, who were not traveling together, were isolated along with their parties. They all disembarked in Syracuse, Sicily.
All passengers on the vessel were required to take two coronavirus tests before boarding; vaccines were not required.
The major cruise lines are preparing to restart operations from U.S. ports this summer. Celebrity Edge is poised to be the first, sailing out of Fort Lauderdale, Fla., on June 26, with all crew and at least 95 percent of passengers fully vaccinated, in accordance with guidelines issued by the Centers for Disease Control and Prevention.
At the beginning of the pandemic in 2020, cruise ships were sites of some of the largest concentrations of coronavirus cases. The return of cruises and large gatherings such as conferences is a sign that the pandemic is ending in the United States, as the steady pace of vaccinations — 43 percent of Americans are fully vaccinated, and 52 percent have received at least one dose, according to a New York Times database — gives some event organizers the confidence to resume business.
This month, Bitcoin 2021, a business conference dedicated to the digital currency, sold 12,000 tickets and attracted thousands more to Miami for a week of panels, parties, networking and deal making. It was the first major business conference since the pandemic and the largest Bitcoin conference ever.
In the days after the event, several attendees announced on Twitter that they had tested positive for the coronavirus. Others shared stories of their peers testing positive.
The event attracted Bitcoin enthusiasts from around the world, including some countries that do not yet have easy access to vaccines. Most events took place inside a large, crowded warehouse, and facial coverings were rare. Vaccines were not required to attend.
John Riggins, head of operations at BTC Media, which ran the conference, said that the company had not heard directly from any attendee who tested positive. The company is monitoring the situation and will follow recommendations from the C.D.C., he said.
“Vaccines have been freely available for months in the U.S., to the extent that anyone who wanted to be vaccinated could have been so by the time of the event,” Mr. Riggins wrote in an email.
“We provided all attendees with the current recommendations of the C.D.C. and state of Florida and expressed to our audience that those who were high risk or hadn’t been vaccinated should consider waiting until next year,” he added.
This week, the first major trade show in the United States since the pandemic started, The World of Concrete, is being held at the Las Vegas Convention Center. The event typically draws more than 60,000 industry professionals from around the world.