Butlins has been hit by a stomach bug laying out 75 of its holiday campers.

The outbreak in Bognor is thought to have started on Wednesday.

Environmental health officers have ruled out food poisoning as a source, and suspect the bug to be a highly contagious norovirus, or "winter vomiting disease".

Butlins guests experiencing symptoms have been advised to stay in their own accomodation and drink plenty of liquid.

Camp spokesman Tom Cassidy said 75 of the 4,000 holidaymakers at the camp were suffering from the virus on Thursday night.

He said: "We think it's a norovirus, but we can't be certain of that.

"Seventy-five out of 4,000 people is not a high percentage.

"In any village of 5,000 people there's always going to be one or two people who are sick or have flu."

Outbreaks of noroviruses are common in institutions where people live or work close to each other, like hospitals, nursing homes, schools and cruise ships.

Butlins alerted health services and told new arrivals about the outbreak as the camp experienced its traditional "changeover day" on Friday.

Mr Cassidy said: "New people coming will be told there has been an outbreak.

"Whether they continue with their holiday or not is up to them."

Health Protection Agency spokeswoman Teresa Cash said experts were giving guidance to Butlins on how to contain the bug.

The camp was not legally obliged to notify health authorities about the outbreak because the bug is quite common.

She said: "If any advice or support is needed we would go in and offer that.

"Unfortunately it is the sort of virus that spreads.

"Our advice is to go home and stay in for 48 hours until the symptoms fade."

Arun District Council environmental health officers visited the camp when news of the outbreak broke.

They investigated the cause and ruled out food poisoning as a cause of the sickness.

A council spokesman said: "It is similar to food poisoning, but it is definitely not food poisoning."

NOROVIRUS - THE FACTS * Noroviruses give between 600,000 and a million people stomach bugs in England and Wales each year.

* The bug is also known as Norwalk-like viruses or SRSV.

* Symptoms last for 12 to 60 hours. Patients experience nausea followed by projectile vomiting and watery diarrhoea.

* Most people make a full recovery within 48 hours, but the very young or elderly may become very dehydrated and need hospital treatment.

* The Health Protection Agency recommends people infected should be isolated for up to 48 hours after their symptoms have ceased, and drink plenty of fluids to prevent dehydration.