New case of Mpox Clade 1b detected in UK amid health warnings

A fourth case has now been confirmed of a new strain of mpox in the UK - meanwhile the UK Health Security Agency said all of the cases belonged to the same household

Another case of the new strain of mpox has been detected in the UK, health officials have said.

The total number of confirmed cases of the Clade 1b variant in the UK to four. The UK Health Security Agency (UKHSA) said all of the cases belonged to the same household.

It comes after the World Health Organisation declared a "public health emergency of international concern" in August following a deadly surge in Africa – with 19 countries reporting more than 48,000 suspected mpox cases and 1,048 deaths this year so far, according to Africa CDC.

The Clade 1b strain of Mpox has been detected in household contacts of the first UK case, confirmed just last week in London - bringing the total number of confirmed UK cases to four. Clade 1 is known to be a more severe strain of the virus, and was responsible for at least 450 deaths during an initial outbreak in Congo.

The newer and more deadly strain, known as Clade 1b, later spread to Sweden, before moving over to Germany, India and Thailand.

Mpox is a viral infection that usually causes flu-like symptoms and pus-filled lesions across the body. While it is usually mild, severe cases can kill. Clade 1b is a different form of the virus from Clade 2, which spread globally in 2022, largely among men who have sex with men. Both forms can be transmitted through close physical contact, including sexual contact.

The new patient is currently receiving specialist care at Guy’s and St Thomas’ NHS Foundation Trust in London. The UKHSA says risk to the UK population remains low, and there has been "extensive planning" to ensure healthcare professionals are equipped and prepared to respond to any further confirmed cases.

Professor Susan Hopkins, Chief Medical Adviser at UKHSA, said: "Mpox is very infectious in households with close contact and so it is not unexpected to see further cases within the same household. The overall risk to the UK population remains low. We are working with partners to make sure all contacts of the cases are identified and contacted to reduce the risk of further spread."