MIAMI (Bloomberg) — Royal Caribbean Cruises Ltd., the world’s second-biggest cruise operator, said a two-day departure delay on the largest cruise ship will reduce earnings by three cents a share in the fourth quarter.

Hundreds of Freedom of the Seas passengers and crew were sickened with a gastrointestinal illness called norovirus on two successive voyages. The ship left Miami on a voyage on December 12, two days later than planned, after the US Centers for Disease Control and Prevention recommended the vessel receive extra cleaning, Royal Caribbean said in a regulatory filing.

Royal Caribbean is shortening the seven-day Caribbean sailing to five to use special disinfectants and clean “high- touch” areas such as door handles and elevator buttons.

More than 300 of 3,823 guests were sickened with norovirus during a sailing from November 26 to December 3 and 97 of 3,907 guests became ill on a voyage the following week.

Royal Caribbean in October forecast fourth-quarter profit of 20 cents to 25 cents a share, including costs of two cents to three cents from the acquisition of Spanish cruise operator Pullmantur SA. The Miami-based company said it expects to earn $2.90 to $2.95 a share for the year.

Freedom of the Seas, launched in May, is sailing a revised five-night trip in the Caribbean. It will resume seven-night voyages on December 17, Royal Caribbean said in the filing with the US. Securities and Exchange Commission.

More than 90 percent, or 3,630, of guests originally booked on this week’s delayed trip departed, said Royal Caribbean spokesman Michael Sheehan.

Royal Caribbean added two doctors to the December 12 sailing, for a total of four.

The cruise line gave passengers who chose to still go on the trip a 50 percent refund of their fare, two nights’ hotel stays for those don’t live in South Florida, $250 for meals and transportation and a 50 percent discount on a future voyage. Those who cancelled may receive a full refund.

Shares of Royal Caribbean fell 16 cents to $40.17 at 4.03 p.m. in New York Stock Exchange composite trading.

The stock has fallen 11 percent this year. Miami-based Carnival Corp. is the world’s largest cruise operator.