A woman who returned from Dubai ten days ago to support her mother after her father was diagnosed with cancer, has become the latest person to challenge the legality of her detention at a quarantine hotel, in what her lawyers described as a "profoundly urgent" application.

A special remote sitting of the High Court was told tonight that 30-year-old Emma Kelly was fully vaccinated and had tested negative for Covid-19 twice before she travelled from the United Arab Emirates and arrived here ten days ago.

Her lawyers told the court she should have been tested again today but has been told she won't receive a test until tomorrow and if negative, she won't be able to leave until the following day.

They have asked the High Court to inquire into the legality of Ms Kelly's detention.

The woman is in quarantine in the Crowne Plaza Hotel, Dublin Airport.

The court will continue hearing the case in the morning when the State will be given a chance to respond.

Senior Counsel Mícheál P O'Higgins told the court Ms Kelly was tested the day after she entered quarantine on 3 April and received a negative result. He said she should have been tested again today, on Day 10 of her quarantine and would have been permitted to leave if it was negative.

He said her solicitor had written to the Minister for Health to ask why officials had refused to test her and make arrangements for her departure today.

Mr O'Higgins said Ms Kelly had appealed against her quarantine three times since her arrival but had been refused each time. He said there were compelling humanitarian considerations in her case and requiring her to remain in detention at this extremely difficult time for her family was disproportionate and unlawful.

It was a profoundly urgent case, he said, because it concerned personal liberty and a type of civil detention that wasn't replicated in other countries.

Mr O'Higgins told the court the appeals officers who considered his client's case had deemed the fact that she was vaccinated and had a number of negative test results to be irrelevant because she had come from a designated state.

He said this meant they had not carried out an individualised assessment of the risk she presented. He said the failure to provide her with a Covid test on Day 10 of her quarantine was a marked departure from the procedure laid down by the Oireachtas.

He noted however, that some hotels do not consider the day a person arrives to be Day 1 and there may be a dispute about whether or not today is Day 10.

The court was also told Ms Kelly suffered from anxiety and was under severe stress as a result of her father's diagnosis. Her mother had asked her to return home urgently from the UAE to help care for him.

Mr Justice Brian O'Moore said one of the issues he would have to decide was whether or not Ms Kelly was actually in detention.

He acknowledged the urgency of the case and adjourned it until tomorrow morning.