The North's first case of swine flu was confirmed today.
The man, who had returned from Mexico, is at home and responding well to treatment, according to the Department of Health.
Health minister Michael McGimpsey said: “He is responding well to antiviral treatment and I hope he makes a full recovery as soon as possible.”
The swine flu victim had recently returned to the province after a two-week holiday in Mexico with his wife and children.
He is being treated with anti-virals and is recovering well at home.
Health authorities are urgently seeking to contact the 151 passengers and crew who were on an easyJet flight from Gatwick to Belfast last Friday.
The swine flu sufferer and his family travelled on the 5.40pm flight on the last leg of their journey home on May 8.
So far 25 people with whom he has been in contact, including family members, have been identified and are receiving the anti-viral drug Tamiflu.
Mr McGimpsey said: “People should not be alarmed by this development. We have been planning for a situation like this for some years and are well prepared for any potential pandemic.
“It is also reassuring that the majority of cases have had a relatively mild flu-like illness which responds well to treatment with antivirals.
“Northern Ireland has significant stockpiles of antivirals, enough to treat 50% of the population, which is currently being increased to treat up to 80% of the population.
Dr Elizabeth Mitchell, the North’s Acting Chief Medical Officer added: “This is a developing situation which we continue to monitor very closely. The arrangements we have in place, and are continuing to make, will help us respond well to any emerging situation.
“Everyone needs to play their part to protect and prepare themselves and their families.
“Simple, effective measures such as frequent hand-washing with soap and water and using a tissue to cover your mouth and nose when sneezing can help reduce the spread of flu.”