Swine flu concerns will keep Carnival Cruise Lines away from Mexican ports of call longer than previously expected.
The company said Friday it has modified itineraries through May 11 to avoid the country — a week longer than it announced earlier. Most ships are stopping at alternate ports.
Some trips are being lengthened. Four- and five-day cruises from Galveston and New Orleans have been turned into seven-day voyages.
The five-day passengers can take the extended trip for free, but four-day cruisers will have to pay a little extra. Those guests can also rebook or get their money back.
Passengers with less drastic itinerary changes will also have the option to rebook a future cruise.
Carnival is diverting three of its ships from Mexico to the U.S. Virgin Islands. The USVI Department of Tourism says the ship "Glory" will arrive in St. Thomas every Tuesday from May 5-19. The ship can accommodate nearly 3,000 passengers.
The arrivals could help boost lagging tourism numbers on the islands.
The Caribbean Tourism Organization says the islands saw a 16 percent drop in cruise ship passengers from January through March of this year compared to the same period last year.