As the group flew back to Scotland, some 40 of the 60 passengers told cabin crew they felt ill.

Today Mr Urquhart, an accountant, said, “Me and my room mate felt really ill the last two days and I pretty much slept for 40 hours out of 48.

“Me and five of my mates all got it. I didn’t go to the doctor but waited until I landed in the UK.

“I got back on Wednesday last week and I was told I swine flu on Friday.

“It’s odd. I have basically just felt really fatigued and tired. I have a bad cough too. It means I sleep all day and then at night, when I need to sleep, I can’t because of my cough. I am really bored as well, just sitting in the house all day.”

The group visited several well-known clubs and bars during the week-long trip.

Robert’s friend, William Forbes, also 19, was part of the group but appears not to have caught the bug.

He said the holiday was the “best ever” until he heard about his friends’ illness.

The apprentice electrician said, “I am feeling fine. I have been taking Tamiflu as a precaution but I am not in quarantine.

“I sat next to Daniel on the bus and he was saying he felt really ill.”

Robert’s mum Teresa said the whole family had been told to take antibiotics and stay at home.

“When he was on the plane the air hostess asked everyone who had felt ill on holiday to press the buzzer and around 40 out of 60 people pressed it,” she said.

“There are five of us all taking antibiotics at the moment and I can’t go back to work.”

It is thought the men who contracted the virus are Robert Urquhart, Daniel Beg, Innes Rust, Keiron Grant, Nicki Craig and Amos McMillan. All those confirmed to have the A H1N1 virus have been told to stay at home and prescribed antibiotics.

The other men have been given Tamiflu as a precaution but will not be tested unless they begin to show symptoms.

Dr Drew Walker, NHS Tayside director of public health, said the increase in the number of cases in the region was consistent with what had been seen in other areas.

“The vast majority of people contracting the virus are experiencing mild symptoms and the risk to the general public remains low,” he said.