A gastro outbreak has struck the same major cruise ship for the second time in a fortnight.
The Sun Princess was docking in Brisbane on Thursday after dozens of passengers were struck down with norovirus on a two-week cruise to New Zealand.
It's understood more than 140 passengers fell ill.
ABC digital producer Kathryn Perrott said she and her brother flew home early from Auckland on Sunday after the captain announced an outbreak on the loudspeaker.
"We had cabins all around us being cleaned by people in hazmat suits," she told ABC radio Brisbane.
The illnesses came after about 90 people were struck down by the illness in its previous trip.
Sun Princess owner Carnival Australia put out a statement saying most guests were unaffected by the "common 'stomach bug'".
"On any given day during the cruise 12 to 15 of the 2000 guests were in self isolation while symptoms ran their course before they returned to their usual cruise activities," a spokesman said, in a statement.
"At no stage during the cruise was there a large number of guests ill at any one time."
Ms Perrott posted to Facebook a week ago to say staff in suits were cleaning the room opposite her and told her the occupant had been taken to the ship's hospital.
"We also saw them cleaning the room two doors down from us this morning," she wrote.
"This afternoon, I overheard a woman saying her partner had been 'doing all the right things', washing his hands etc but still became sick and the experience had turned them off cruising in future."
The Carnival Australia spokesman said norovirus was common and had been active in Australia in recent months.
"While the risk of Norovirus is 750 times greater on land than at sea, when it happens on a cruise ship, already high sanitation levels are increased further including encouraging guests to regularly wash their hands with warm water and soap and to use hand sanitiser machines located on board," he said.
"Guests would have seen evidence of the proactive measures being employed on board and heard numerous announcements as part of our transparent approach in these matters."