A woman whose daughter died after contracting swine flu has appealed for people to get the vaccination after a schoolboy from Northern Ireland was flown to a Scottish hospital with the virus.
The seven-year-old boy from Belfast was initially admitted to the Royal Belfast Hospital for Sick Children at the weekend.
But he later had to be transferred to Glasgow for treatment.
It is believed the young boy had difficulty breathing and needed an ECMO machine.
It is used for babies and children with severe heart or lung failure and is similar to a heart-lung bypass machine used for open-heart surgery.
The machine works as an artificial lung outside the body that puts oxygen into the blood.
A spokeswoman for the Belfast Trust said it does not discuss an individual's patient treatment or care.
Almost 30 people in Northern Ireland died after an outbreak of swine flu in 2009 – known as the H1N1 strain.
The majority of those who died had underlying health issues.
Corrina Ritchie from Belfast died in 2009 after contracting swine flu on holiday in Spain.
The 21-year-old underwent a liver transplant but sadly died of complications.
Lorraine Ritchie, her mother, said it was important to remember how serious swine flu can be.
"My thoughts are with that little boy's family," she said.
"I know when we were told Corrina had contracted swine flu we were just so shocked."
Ms Ritchie (49) added: "I think people have forgotten how serious it can be for people who have underlying conditions."
She said it was important for people to be aware of the symptoms and to get the flu vaccination. Swine flu is now classed as seasonal flu. There are currently 22 cases in Northern Ireland.
A spokeswoman for the Public Health Agency said: "The strains circulating this year include H1N1 and this strain has already been found in small numbers of people in Northern Ireland, and as such, is not unusual."
The symptoms are very similar to other types of seasonal flu. Most people recover within a week, even without special treatment.
Flu symptoms usually peak after two or three days and you should begin to feel much better within five to eight days. If you are becoming more ill, or you are in an at-risk group, then contact your GP for advice.
For information on seasonal flu, go to www.fluawareni.info
Influenza (commonly referred to as 'seasonal flu') is a respiratory illness associated with infection by influenza virus. Seasonal flu is made up of several strains including H1N1 (swine flu).
This year's seasonal flu vaccines include protection against H1N1.
Swine flu is a relatively new strain of flu that caused a pandemic in 2009-2010.