katharine craig. >> reporter: as passengers on the anthem of the seas disembarked the cruise ship, workers went into the empty cabins and scrubbed them inside and out. workers wiping down balcony furniture. for the second time in recent weeks the vessel cut short its trip. royal caribbean says it's returning two days early because of severe weather. passengers tell us a number of people became sick with the norovirus. >> they said it was limited, few people and took a lot of extra precautions with sanitation. >> reporter: nbc news learned more than 150 people became sick with the norovirus. they were given over-the-counter medicine and doing well. passengers told about illnesses afew days into the start of the trip. >> we didn't get sick. a few people got sick. an older person got sick. just a few of them. >> virus, very little. with ships as clean as a whistle. >> reporter: the same cruise ship rocked weeks ago during a storm. huge waves, deck furniture thrown around. royal caribbean says the campaign is following the new storm avoidance policy which forced early return this time. >> that