A Co Down woman who is taking part in a UK Government Covid-19 survey was not told for almost three weeks she had the virus, it can be revealed.
She tested positive at the end of last month. But, in the latest worrying development as Covid-19 spreads out of control, she was only informed of the result this week.
She expressed horror that she may have unwittingly passed on the virus to colleagues and family, including her sister, who is a nurse
"The more I think about it, the more angry I become," she said.
"I can't believe how it's possible that I can have the virus but only hear about it in a letter sent weeks after the test is done."
Earlier this year she was asked to join the Coronavirus Infection Survey Pilot, a Government programme aimed at estimating the number of people with the infection in England, Wales and Northern Ireland.
"I'm in a bubble with them, they have young children and my sister is a cancer nurse, I'm so worried - but no one seems to care."
The survey is being delivered in partnership with the University of Oxford, University of Manchester, Public Health England and Wellcome Trust.
The Department of Health has been working alongside the Public Health Agency, Northern Ireland Statistics and Research Agency and ONS to extend the survey to Northern Ireland. Fieldwork began on July 27.
It is not known whether a process is in place to ensure our test and trace programme is informed of positive cases.
Alliance Party health spokeswoman Paula Bradshaw said on Thursday night: "This concerning story merely adds to the significant confusion that exists around what different programmes are supposed to do.
"Clearly, during a public health emergency, if any organisation has evidence that someone has tested positive for the virus it is incumbent on the organisation to communicate that without delay."
The ONS said: "Covid-19 Infection Survey is a research study, not a testing programme. We clearly state in our participant information that if people have symptoms, they should get a test through the NHS.
"We do communicate both positive and negative results directly back to all our participants and seek to notify anyone with a positive result by telephone and letter."