The accident, which the company has blamed on the ship's captain, has soured the company's image in the midst of the industry's peak booking period.

WSJ: Cruise Operators See Shares Fall, Defend Safety

Industry guidelines say patients should have a two-week cooling off period after booking procedures and they ban the use of time-limited financial inducements.

BBC: RELATED BBC SITES

Delta's short-term booking rate increased 35 points over the same period in 2012.

WSJ: Frequent-Flier Miles: Best Airlines for Cashing In