Significant Increase in Mpox Cases in Northern Ireland
The Public Health Agency (PHA) has confirmed that 21 cases of mpox have been detected in Northern Ireland over the last three weeks. Prior to this, only nine cases had been reported in the region since the beginning of 2023, marking a notable increase in recent weeks.
The current cases are predominantly among men who have sex with men. The PHA has advised those eligible for vaccination to contact their local sexual health clinic.
"Over the last three weeks we've had 21 cases of mpox diagnosed in Northern Ireland.
To put that into context, through the rest of 2026 up 'til now we haven't had any cases of mpox diagnosed, so it does represent a quite a quick increase in the number of cases being diagnosed here."
— Dr Rachel Coyle, consultant in health protection at the PHA, speaking to NI.
Context and Background on Mpox in Northern Ireland
With mpox cases rising across Europe and the UK, it was anticipated that Northern Ireland would eventually see an increase. Mpox, formerly known as monkeypox, was first detected in Northern Ireland during the global outbreak in 2022.
Dr Rachel Coyle explained that there has been a change in the strain of mpox since the initial outbreak.
"We talk about two different strains of mpox. In 2022 it was the clade II strain that was mostly circulating, now we're talking about clade Ib, so it's a slightly different strain."
During the 2022 outbreak, Northern Ireland recorded 34 cases of mpox. Between 2023 and June 2026, only nine cases were detected, all of which were the clade II strain. The 21 cases identified in June 2026 are all clade Ib, representing the first detection of this strain in Northern Ireland.
What is Mpox?
Mpox is caused by the monkeypox virus, which belongs to the same family of viruses as smallpox but is generally less severe. Initial symptoms include fever, headaches, swelling, back pain, and muscle aches. After the fever subsides, a blistering rash may develop, often starting on the face or genitals and spreading to other parts of the body. The rash progresses through stages including flat spots, raised spots, blisters, and scabbing.
Individuals infected with the virus are advised to abstain from sexual activity while symptomatic to prevent transmission.
With several Pride events scheduled for the summer, those eligible for vaccination have been urged to receive it.
Vaccination Eligibility
The Public Health Agency has encouraged vaccination for those most at risk but noted that individuals who completed the vaccine course in 2022 do not require another dose.
"While anyone can catch mpox, the majority of mpox cases in the UK are in gay, bisexual and other men who have sex with men (GBMSM)," said Dr Coyle.
"Therefore, those eligible for the vaccine include gay, bisexual or other men who have sex with men who have multiple sexual partners, and those who participate in group sex or attend sex on premises venues.
Vaccination is available for those eligible in Northern Ireland through sexual health clinics.
This is particularly relevant as we head into the summer months and many more people will be travelling."
