Passengers on a recent cruise ship visit to Tauranga had to be confined to their cabins thanks to an on-board outbreak of the norovirus.

The Dawn Princess passed through Tauranga last Wednesday, but many of her 1500 passengers weren't allowed to disembark before departing for Napier the same evening.

The Dawn Princess alongside at the Port of Tauranga.

Today more than 200 passengers remain restricted to their cabins with the vomiting and diarrhoea bug, while the ship heads towards Dusky Sound, Doubtful Sound and Milford Sound in Fiordland.

Cruise operators Carnival Australia have informed New Zealand health authorities of the outbreak.

Speaking to Stuff, Canterbury District Health Board medical officer of health Daniel Williams says: 'We were told by the ship's doctor that the number of new cases were slowing down, but there were still new cases.

'It is very easily spread from person to person and it can be quite difficult to contain when people are living close together. The best way to stop this sort of bug from spreading is to stay away from people until the symptoms have settled.”

Passengers needed to be isolated for 24 hours after symptoms had settled. The symptoms take anything from one to three days to pass, but passengers who are ill or have not recovering aren't allowed off the ship when it docks.

Passengers were succumbing to the stomach bug and being confined to their cabins across two decks within a day or two of the ship's departure from Auckland, says one comment on the story.

Meanwhile staff on board are implementing stringent sanitation, disinfecting railings, door handles and lift buttons. Self-service food areas are closed as passengers remain isolated.

Norovirus is highly infectious and can spread easily from person to person. The virus can survive on contaminated surfaces even after cleaning with some disinfectants, states The Ministry of Health's website.

Those with the norovirus are infectious for at least three days after the symptoms stop and can be infectious for up to two weeks.

Norovirus can be spread through contaminated food or drinks, touching contaminated surfaces or objects, having direct contact with an infected person by sharing food or eating from the same plate or cutlery and through the air when vomiting sends tiny particles into the air.

Today the Dawn Princess is here. She is expected to return to Tauranga on December 21.

The cruise ship in port today is Celebrity Cruises' Celebrity Solstice which arrived from Wellington earlier and is expect to depart for Auckland at 5pm.