A NEW case of the mutant strain of mpox has been detected in England, the UK Health Security Agency (UKHSA) has announced.
The new infection, detected in East Sussex, brings the total number of confirmed clade 1b mpox cases in the UK to six.
The unnamed patient has since been moved to the Guy's and St Thomas' NHS Foundation Trust, in London, where they are receiving specialist care.
Despite the rise in infections since October 2024, health chiefs insist the risk to the UK population "remains low".
The new case is unrelated to previous ones, most of which were traced to a single household in London.
Officials don't yet know how the new person became infected with the strain.
However, they know they had recently returned from Uganda, where the disease is currently spreading.
The agency is following up close contacts of the infected person.
Contacts will be offered testing and vaccination where needed to prevent the infection spreading, the UKHSA said on Monday.
The new mpox variant differs from those circulating in the UK since 2022, appearing to be more contagious while remaining equally deadly.
Dr Meera Chand, from the UKHSA, said: "It is thanks to clinicians rapidly recognising the symptoms and the work of our specialist laboratory that we have been able to detect this new case.
"The risk to the UK population remains low following this sixth case, and we are working rapidly to trace close contacts and reduce the risk of any potential spread."
The UK reported its first case of the new strain in late October, since then cases have been spotted in London, Leeds and now East Sussex.
"Extensive planning" has been carried out so healthcare professionals are equipped and ready to respond to any further confirmed cases, the agency said.
Germany also reported its first case in October, following Sweden's first case in August.
Belgium reported two cases in December 2024, and France a single case this month.
Mpox, previously known as monkeypox, is a viral infection that causes flu-like symptoms and pus-filled lesions.
The new clade 1b variant started spreading rapidly in the Democratic Republic of Congo (DCR) last year.
There have been cases reported in Burundi, Rwanda, Uganda, Kenya and India.
Since then, it has infected more than 25,000 people and is responsible for more than 1,000 deaths.
This prompted the World Health Organisation (WHO) to name the increasing spread of the disease a global health emergency for the second time in two years.
Mpox mostly spreads via close contact with infected people, including through sex.
Common symptoms include a skin rash or pus-filled lesions which can last two to four weeks.
Professor Jonathan Ball, of Liverpool School of Tropical Medicine, previously said the new UK cases were not "not unexpected".
"There are active human-to-human transmission chains of Clade 1b monkeypox infections in several countries in sub-Saharan Africa, and therefore people coming into close contact with anyone infected is at risk."
The clade 1b strain of mpox was discovered by scientists earlier this year, who traced it to a Congolese mining town.
Scientists from the Africa Centres for Disease Control and Prevention (Africa CDC) declared a public health emergency over the new strain in August.