Windstar Cruises will require passengers on its cruises, currently launching in June, to be fully vaccinated against Covid-19.
Windstar said it had arrived at the decision "in the best health and wellness interests of its guests, crew and the places the yachts visit."
"Vaccination is another layer of safety for all of us, and it's the responsible course of action as our yachts resume cruising and our guests travel the world," Windstar president Christopher Prelog said in a statement.
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The line said that increased vaccine availability in the U.S. and abroad give it confidence that passengers who wish to sail with the line will have time to be vaccinated before travel. Windstar's crew will also be required to be vaccinated as soon as the vaccine is available to them.
Windstar currently plans to resume service in June from the Mediterranean and the Caribbean in a phased manner, with initial cruises at reduced occupancy and with enhanced health and safety protocols in place.
Its first ships to launch service are slated to be the Star Breeze, launching from Philipsburg, St. Maarten, and the Wind Star, departing from Athens, both on June 19.
They will be followed by the Wind Spirit on July 15 from Papeete, Tahiti; the Wind Surf on Aug. 8 from Barcelona; the Star Legend from London on Sept. 4; and the Star Pride from San Juan on Nov. 3.