Up to four people have been treated for the Zika virus in Northern Ireland.
The Public Health Agency (PHA) confirmed to the BBC that fewer than five patients were infected with Zika, with one being treated last week.
The virus is spread by bites from the Aedes aegypti and Aedes albopictus species of mosquito, but it can also spread through sexual intercourse. It is not clear where the cases in Northern Ireland originated.
The World Health Organisation has described the Zika virus as a global health emergency. The mosquitoes carrying the virus are common in South America, Africa and Asia. Zika is linked to thousands of babies born with underdeveloped brains. There have been 117 confirmed cases of the Zika virus in the UK over the past 12 months.
A PHA spokesperson said there was no specific treatment for Zika, other than hydrating patients with the symptoms.
The agency said it was not its policy to give out the exact number of diagnosed Zika cases, because the figure was fewer than five and doing so could identify those affected.
