Travel agents say customers are still booking trips that include visits to destinations like Puerto Vallarta and Mazatlan, but those itineraries are likely to change if the outbreak gets much worse. The federal government has warned against nonessential travel to Mexico.

Jennifer Michaels, an Atlanta real estate broker, is stocking up on antiseptic wipes ahead of a five-day Carnival Cruise Lines voyage leaving Miami on Thursday.

She hoped Carnival would skip a planned stop in Cozumel, but said she and her friends would go even if it didn't.

"We'd probably still go and then just stay on the ship if they stop," she said. "I don't know if that would do any good anyways, but that's what we'd do."

Michaels got her wish. After cancelling three scheduled stops in Mexico on Tuesday, the company said it would suspend all calls in the country for every ship now at sea and those leaving between Thursday and May 4.

Carnival is offering alternate ports on many trips, but will allow customers to reschedule if they wish.

Debbie Rauch, owner of Great Escapes Cruises and More in Lighthouse Point, Fla., said most of her clients aren't worried. One woman booked a trip Monday that will take her to Mexico in two months.

"She really didn't seem that concerned at this point," Rauch said. "If it's going to become a pandemic and it's going to be everywhere, it probably doesn't matter where you go."

But some cruise lines, like Carnival, have decided Mexican ports of call aren't worth the risk. Holland America said its ms Ryndam is no longer calling on Mazatlan while the company confers with public health officials.

Princess Cruises canceled calls in Puerto Vallarta and Cabo San Lucas on Tuesday and diverted its Sapphire ship from Mexican ports to San Diego and Catalina.

Meanwhile, Royal Caribbean International and Norwegian Cruise Lines, along with their competitors, told passengers their ships are carefully cleaned and they don't need to worry.

Norwegian's Pearl is on a special voyage with Mexico stops, which are going on as planned, but won't have regular calls there until September. The company says it is monitoring the situation and asking passengers about their health before cruises start.

Royal Caribbean is telling passengers not to worry because the outbreaks are inland, not in the Mexican coastal cities popular with cruise tourists. Still, the operator is putting daily notices in the onboard newsletter about the outbreak and providing hand sanitizers throughout the ship.

Devin Fleming, owner of Upper Crust Travel in Miami and London, said his most die-hard customers are still happily planning trips that include Mexico stops, though that could change.

He compared the swine flu to the norovirus, which causes stomach problems and has sickened hundreds of passengers on cruise ships in recent years.

"You've got to wash your hands and really be diligent about that," Fleming said.

Evan Hanna, of Stafford, Va., was already at sea and headed to Grand Cayman and Cozumel when he and other passengers got word their Carnival ship would skip Mexico.

"There was a lot of yelling at the ship's officials," Hanna wrote in an e-mail from the oceanliner. "Most passengers still wanted to go to Cozumel, and there were a lot that wanted to go back to the home port early."

By Tuesday afternoon, most had gotten over it, Hanna said.

"Everyone seems to have calmed down, and its just like any other day at sea," he wrote.
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