The first case of monkeypox has been detected on the island of Ireland.
The NHS has confirmed a case of the disease in Northern Ireland.
Health officials in Northern Ireland are expected to hold a briefing later on Thursday.
Despite the rise in cases, the UKHSA has said the risk to the overall UK population “remains low”.
Gay, bisexual and men who have sex with men are being urged in particular to be aware of symptoms, especially if they have recently had a new sexual partner.
UKHSA teams have been tracing contacts of those with a confirmed case and are advising those at highest risk to isolate for 21 days.
A smallpox vaccine is also being offered to close contacts to reduce their risk of symptoms and severe illness.
There have been no cases confirmed in the Republic of Ireland, but the HSE have said they will monitor any possible cases for 21 days and have advised any close contacts or people with symptoms to self-isolate.
Nearly 20 countries where monkeypox is not endemic have reported outbreaks of the viral disease, with more than 100 confirmed or suspected infections mostly in Europe.
The outbreaks are raising alarm because monkeypox, which spreads through close contact and was first found in monkeys, mostly occurs in west and central Africa, and only very occasionally spreads elsewhere.
Below is a list of countries that have so far reported suspected or confirmed cases, in alphabetical order:
Australia on May 20 reported its first case in a traveller who recently returned from Britain. Another suspected case was also identified.
Austria confirmed its first case on May 22.
Belgium detected two cases on May 20.
Czech Republic detected its first case on May 24.
Denmark confirmed a second case on May 24, a day after the first.
Finland discovered a "highly likely" first case, Helsinki hospital district said on May 25.
France’s number of confirmed cases rose to five on May 25.
Germany has confirmed three cases, with the first registered on May 20.
Italy has confirmed six cases by May 25. It detected its first case on May 19.
The Netherlands reported its first case on May 20. It has since confirmed "several" more patients, without stating the exact number.
Portugal reported 10 new confirmed cases on May 25, bringing the total to 49.
Slovenia confirmed its first case on May 24.
Spain confirmed seven new cases on May 25, bringing the country's total to 55.
Sweden confirmed its first case on May 19.
Switzerland reported its first confirmed case on May 21.
The UK detected 14 new cases in England on May 24, taking the total of identified cases to 70.
Israel confirmed its first case on May 21.
The United Arab Emirates detected its first case on May 24, state news agency WAM reported.
Argentina reported its first suspected case on May 23. No cases are yet confirmed in South America.
Canada has confirmed 15 infections in the Quebec province as of May 24. The province's health department said more cases from other parts of the country were expected.
The United States has confirmed two cases, the first on May 18. A third case is suspected as of May 23.