Health officials on both sides of the border are on alert following the first confirmed case of Covid-19 in Northern Ireland.
The adult patient had returned from northern Italy, travelling from Dublin, chief medical officer Dr Michael McBride said.
He said the individual had contacted a GP and had taken steps to self-isolate. He also confirmed only a small number of people have been in close contact with the person.
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He refused to be drawn on whether the person had travelled from the Republic to Northern Ireland via public transport. He would only say the patient was not part of a school trip.
.@publichealthni is working on a cross-border effort to identify people who may be at higher risk after close contact with a person diagnosed with Coronavirus in Northern Ireland. They’d traveled from Northern Italy via Dublin. @RobinSwannMoH has also spoken to @SimonHarrisTD pic.twitter.com/TCDG99ev4W
— David Hunter (@davidhunter7) February 28, 2020
While the individual's gender was not revealed, there were suggestions it may be a woman from south Belfast.
It is also believed a child, understood to be the woman's daughter, is being tested for the virus.
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The positive result has been sent to Public Health England laboratories for verification.
A special unit has been established at the Royal Victoria Hospital in Belfast for isolating those suffering from the virus but the health authorities were unable to confirm where the individual is being treated.
"We have been planning for the first positive case in Northern Ireland and have made clear that it was a question of when not if," said Dr McBride.
"We have robust infection control measures in place which enable us to respond immediately.
"Our health service is used to managing infections and would assure the public that we are prepared."
He added: "We have now seen our first case in Northern Ireland of someone returning from northern Italy and that is not unexpected.
"We have well-trialled and tested methods for identifying people who have been in contact... following up giving them advice and taking appropriate steps to protect the public."
The individual followed advice in reporting concerns to a GP and "self isolated" at home whilst awaiting the results of testing.
The Republic's health minister, Simon Harris, said it was "not unexpected" and is to meet staff at Dublin Airport activating the public awareness campaign for Covid-19 this morning.
The Republic's National Public Health Emergency Team has been planning for this scenario since January.
The minister said the public should continue to adhere to public health protocols issued by the Department of Health.
Dr Tony Holohan, chief medical officer in the Department of Health told RTÉ news, the individual who was infected came forward and followed the instructions given by health authorities.
He said the Health Service Executive in the Republic will be contacting people who sat within two rows of the person on the plane from northern Italy to Dublin.
