Lives are at risk amid alleged discrimination in Northern Ireland's vaccination programme, the High Court heard today.
Lawyers for a Co Fermanagh man with a rare genetic disorder claimed backroom NHS staff were wrongly prioritised over vulnerable groups for Covid-19 jabs.
Lee Martin is seeking to judicially review the Department of Health's handling of the scheme.
With the 36-year-old having received his first dose of the vaccine, a judge was told the case is now academic.
But Mr Lavery's barrister, Ronan Lavery QC, argued: "These are life and death issues.
"It was at the time, and if this individual had contracted the virus we would be in a very different situation now."
Mr Martin, from Enniskillen, is one of less than 100 people worldwide diagnosed with diploid triploid mosaicism (DSM).
His condition, which occurs when someone has two different types of cells with different numbers of chromosomes, means he requires 24-hour care.
He was classified as extremely vulnerable and put in category four on a priority list under the Department of Health's Covid-19 Vaccination Programme Phased Plan.
That placed him below some healthcare staff against the Guidance of the Joint Committee on Vaccination and Immunisation (JCVI), it was alleged.
Legal proceedings were issued earlier this year in a bid to have him fast-tracked for the vaccine.
It was contended that Mr Martin faced discrimination because of a priority scheme which left him fearing he would contract coronavirus and die.
Further grounds of challenge involve claims of irrationality and breach of human rights.
Mr Martin received his first jab in February, after commencing legal action, and is due to get his second dose later this month.
According to Philip McAteer, for the Department, those developments rendered the proceedings academic.
"This is an application about a discreet, historic period of a unique vaccination programme," he said.
But Mr Martin's legal team insist the case involves wider issues of public importance for a cohort of thousands of other clinically vulnerable individuals.
"People's lives are actually at risk," Mr Lavery maintained.
Reserving judgment on the application for leave to seek a judicial review, Mr Justice Colton pledged: "I will give a ruling shortly."