The cruise Zenaiva Cervantes booked was to stop in sun-drenched beach cities on the Mexican Riviera. The cruise she took? That landed her in Seattle, where she pulled her arms tightly to her chest as she debarked on a damp, 50-degree morning.

“We wanted to relax in the warmth,” the 61-year-old Tijuana, Mexico, resident said in Spanish Thursday. “If someone had told me I’d be in Seattle eight days ago, I wouldn’t have believed them.”

At the peak of the swine flu outbreak, major cruise operators Carnival Corp. and Royal Caribbean Cruises Ltd. — desperate to avoid passenger illness and lost revenue — decided to reroute Mexico voyages until mid-June.

So even though fear has receded, once-sun-seeking passengers like Cervantes are finding themselves in San Francisco, Seattle and Victoria, British Columbia, in Canada. Cruise companies are compensating passengers for the switch with onboard credit plus vouchers for a future cruise. Passengers also had the choice to stay home and get a full refund, but most passengers are choosing to travel when they planned, the cruise lines said.

What they’re losing in sunshine and tan lines, their new destinations are gaining in millions of dollars of business. In San Francisco, the 16 additional swine flu-related landings will boost the year’s port traffic 31 percent and bring 49,000 new visitors, said Michael Nerney, San Francisco’s maritime marketing manager. Each call could mean $1 million in sales for city businesses and together they’ll produce $500,000 in revenue for the port.

“This is highly unusual — shocking, really — as the cruise lines set their sailing schedules 12 to 18 months in advance, and even minor changes are rare,” Nerney said.

The great number of alternative ports in the Caribbean makes it far easier to swap stops there. Instead of Cozumel in Mexico, companies are opting for Ocho Rios or Montego Bay in Jamaica, Nassau or Freeport in the Bahamas, the Virgin Islands’ St. Thomas, St. Maarten or Key West, Fla., or points across the Caymans and Turks and Caicos.

The Bahamas is happily awaiting diverted ships. Customs receives $15 for each passenger, and island clothing and jewelry shops, bars and cafes depend on tourist dollars, said tourism minister Vincent Vanderpool-Wallace said.

Analysts think the benefits may be fleeting for these ports because the outbreak hasn’t been severe.

“I think it’s a short-term bump that may already be dissipating,” said Michael McCall, a hospitality research fellow and lecturer at Cornell University.