A northern Europe dream holiday has turned into a floating nightmare as holidaymakers are reportedly “dropping like flies” due to a severe strain of the novovirus sweeping through a P&O cruise liner.

The luxury ship, Iona, which carries over 5000 guests and nearly 2000 staff is reportedly dealing with an outbreak of the virus which can lead to gastrointestinal upset, cramps, vomiting and diarrhoea.

Sky News UK is reporting that the onslaught of the virus has caused hundreds of passengers to fall ill with the company releasing statements providing updates as the situation grows worse aboard the ship.

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The ship, which is currently located off shore near Belgium as the seven-day cruise continues on with staff endeavouring to isolate the affected passengers and restrict their movements both aboard the ship and land-based stopovers.

“People were throwing up in restaurants, on decks, outside cabins,” one of the passengers told Sky News.

“A large number of guests and staff are experiencing the virus symptoms.”

P&O Cruises confirmed that some guests have reported symptoms of gastrointestinal illness but refused to provide an update on the health of cruise staffers.

“P&O Cruises works with global, national and regional public health authorities on approved and proven protocols across our ships in order to protect the health and wellbeing of all on board,” a P&O spokesperson said.

“Gastrointestinal related illness is very common in the UK and is predominantly spread by person to person transmission in environments such as hotels, schools and restaurants.”

What is novovirus?

Norovirus is the most common cause of gastroenteritis and causes diarrhoea, vomiting, and severe stomach pain.

The symptoms usually develop 12 to 48 hours after being exposed and can take three days for a person to fully flush the virus from their system.

Dehydration and weakness due to loss of fluids is common and may effect the elderly in a more profound way.

Novovirus can be spread via contaminated food or water or person-to-person contact. It may also spread via contaminated surfaces or through air from the vomit of an infected person.

Risk factors include unsanitary food preparation and sharing close quarters. and diagnosis is generally based on the obvious symptoms.

The virus is very contagious and spreads quickly with close contact.

P&O have been contacted by The Nightly for comment.