Desperate to woo back travelers who cancelled trips in the wake of Mexico's swine flu outbreak, more than 20 coastal resort hotels have launched a "flu-free guarantee": Guests who catch the H1N1 virus in Mexico — and have the blood test to prove it — can get their next three vacations for free.

The initiative comes as the country's tourism industry tallies staggering losses from a flu epidemic that Mexican officials first confirmed on April 23. The country's official death toll rose to 64 Thursday, with 2,656 confirmed infections. The virus has so far infected nearly 6,500 people worldwide, including 3,352 cases in the USA.

After the Centers for Disease Control and Prevention and U.S. State Department warned travelers against nonessential trips to Mexico, U.S. cruise lines dropped port calls, airlines waived cancellation fees and resorts emptied. On Friday, the CDC downgraded its Mexico travel warning, following lobbying efforts from Mexican hoteliers and the Florida-Caribbean Cruise Association, whose May 5 letter to Pres. Obama noted that "it is now apparent that the health implications of H1N1 are not limited to Mexico, (and) CDC and WHO officials have publicly stated the H1N1 virus is generally no greater health risk than seasonal influenza."