P&O Cruises has confirmed that 'enhanced protocols' will be put in place on a new journey on board Iona leaving Southampton today, after a suspected norovirus outbreak spread on board.

Passengers on a seven-day round trip to Germany, Holland and Belgium that left England on February 15 reported that holidaymakers were "throwing up in restaurants, on decks" and "outside cabins."

It is reported that the captain made a public announcement on Thursday to confirm the outbreak, with passengers having to isolate in their cabins.

Iona returned to Ocean Cruise Terminal this morning and will depart Southampton tonight on another seven-day cruise to Germany, Holland and Belgium.

But as new holidaymakers come on board, P&O Cruises confirmed to the Echo that 'enhanced protocols' will be in place.

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These protocols include guests being asked to declare symptoms before boarding, improved on-board ventilation systems to provide fresh air and increased levels of cleanliness delivered throughout the holiday.

P&O Cruises told the Echo that it works with global, national and regional public health authorities to provide proven protocols across its ships.

The cruise liner said: "All guests travelling or embarking are provided with communications to ensure their wellbeing which is always our is our absolute priority.

"Washing your hands regularly with soap and water, particularly before eating, and after using the bathroom is the best way to protect yourself, and use hand sanitisers where handwashing facilities are not available.

"P&O Cruises provides ongoing advice to guests on every cruise in relation to wellbeing."

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Passengers on board the journey affected by a suspected norovirus outbreak will receive a full refund if they had to isolate or were otherwise unable to join shore experiences.

Those having to isolate reported that staff shortages resulted in issues with food, new towels and new bed linen being delivered to cabins.

A passenger told Sky News: "Even the entertainment has been adversely affected with many of the scheduled acts unable to perform and replaced with a cobbled together entertainment programme to placate the guests.

"What was also incredulous was the inability to buy or get hold of any medication onboard to help with the symptoms. Not one shop or medical centre onboard could supply guests with gastrointestinal suspension medication or replacement salts/fluid sachets."

P&O Cruises confirmed that guests have "unfortunately reported gastrointestinal symptoms" but that the bug was only affecting fewer than 1 per cent of people on board.