A child who was diagnosed with swine flu just over a week ago has died, the Public Health Agency has confirmed.
The eight-year-old girl was a pupil at Ceara School in Lurgan, County Armagh - a special school for children with severe learning disabilities.
Twenty people from Northern Ireland died in last year's swine flu outbreak, including a number of children with severe learning difficulties.
The girl was one of two people diagnosed with the virus last week.
The other case, involving a man from Northern Ireland, was not linked.
A spokesperson for the Public Health Agency (PHA) said the child's death was a reminder that flu infection can cause serious complications, especially in those with certain underlying medical conditions.
"Children who attend schools for those with severe learning difficulties should receive flu vaccines this year and we have written to their parents and to all GPs asking for them to be immunised as soon as possible.
"This year's vaccine protects against three strains of flu, including H1N1 flu.
"While there is no evidence at present that flu is circulating widely in the community, it is impossible to predict when it will.
"We would advise all those who are eligible for flu immunisation to make sure they get it as soon as possible."
The PHA is recommending that all special school pupils have the flu vaccine this year, even if they had the swine flu vaccine last year.
Principals of two schools for children with learning difficulties have told the BBC they would like to see more communication from the Department of Health.
While they did not want to cause panic among parents, one principal said it was better to be proactive before the flu season gets underway.
Symptoms of swine flu in humans appear to be similar to those produced by standard, seasonal flu - fever, cough, sore throat, body aches and chills.
Some people with the virus have also reported nausea and diarrhoea.