The patient developed flu-like symptoms on 22 October and a rash two days later.

An mpox rash of pus-filled lesions can last for up to a month. Other symptoms include fever, headaches and low energy.

The infected UK patient is being treated at the Royal Free Hospital’s specialist high consequence infectious diseases unit in London.

Laboratory testing confirmed the infection was Clade 1b. This form of the virus has been causing mounting concern.

It appears able to spread more easily from person to person through close physical contact, including sex, than other types of mpox.

In Africa, the Democratic Republic of Congo, Kenya, Burundi and Rwanda have all reported cases of Clade 1b mpox this year.

Its close relative Clade 1a is largely connected to exposure to infected animals or eating bush meat.

Clade 1b appears to be milder than 1a, although it’s difficult to know for certain because precise figures on the exact numbers of people infected are hard to pin down.