I hope things go better for my parents as they depart from Ft. Lauderdale tomorrow; but controlling norovirus isn’t just hope, there is some science that cruise lines can use.

Unfortunately science often runs up against economics.

Passengers aboard a cruise ship on which hundreds fell ill recalled days of misery being holed up in their rooms as the Explorer of the Seas returned to its home port Wednesday after a Caribbean trip cut short by an outbreak of stomach flu.

Retiree Bill Rakowicz, 61, from the city of St. Thomas in Ontario, Canada, said he thought he was just seasick when he began suffering from vomiting, pain and diarrhea caused by the suspected norovirus outbreak that sickened nearly 700 passengers and crew.

“Then I went out of my room and saw people with gloves and people sick everywhere,” he said.

He said he had the symptoms for five days starting Jan. 22, the day after the ship departed Bayonne. “It was awful. You feel like you want to give in,” he said.

The U.S. Centers for Disease Control and Prevention said its latest count puts the number of those sickened at 630 passengers and 54 crew members. The ship, on a 10-day cruise that had to be cut short, was carrying 3,050 passengers.

Health investigators suspect norovirus, but lab results are not expected until later this week. If norovirus is to blame, it would be one of the largest norovirus outbreaks in last 20 years, the CDC said. A 2006 norovirus outbreak on a Carnival Cruise Lines ship also sickened close to 700.