TODAY | February 01, 2014
>>> the cruise industry is trying to make a strong comeback this weekend after hundreds of people got sick aboard two different ships this week. kerry sanders has more on the latest incident and why some people won't let this stop them from taking to the high seas .
>> reporter: it's happened again, passengers sick on a cruise ship .
>> we were confined to the room for three days. we didn't get to enjoy any of the meals, any of the shows.
>> reporter: while the centers for disease control reports more than 170 passengers and crew fell ill on the " caribbean princess ," the cruise line says it returned to port in houston a day early "because we were informed that dense fog was expected to close the port for much of the weekend. the ship did not return early because of the increased incidence of norovirus on board." but passengers complained their symptoms on this cruise sound remarkably similar to what close to 700 passengers and crew experienced on their royal caribbean " explorer of the seas " cruise earlier this week. the cdc now confirms that the illness on the royal caribbean cruise was a case of a fast-spreading norovirus . epidemiologists say the number one source of transmission of the norovirus on cruise ships is people touching each other, usually shaking hands. their advice? it may seem odd, but the best thing to do when you meet somebody, bump elbows.
>> on cruises, you have significantly more people than normally you and i come in to contact with on a daily basis, and you're exposed to them for a long period of time.
>> reporter: in new jersey, that other ship, the " explorer of the seas ," was sanitized when it came back to port, easing the next passengers' fears.
>> i know it's going to be clean and they're going to have people on board making sure everything's good.
>> reporter: and despite the rough waters, business is booming, with nearly 21 million people taking a cruise last year alone. for "today," kerry sanders , nbc news, ft. lauderdale.