Nearly 400 monkeypox cases have been identified in the UK for the 2023–2024 period, with four being the more dangerous clade 1b variant, according to the UK Health Security Agency (UKHSA).
Of the 378 cases, 356 were in England, 13 in Scotland, two in Wales, and seven in Northern Ireland. The outbreak of clade 2b variant was first confirmed in England on May 6, 2022.
By the end of 2022, there were 3,732 confirmed and highly probable clade 2b cases in the UK. Before the outbreak, there were only seven mpox cases in the country between 2018 and 2021.
The 2022 outbreak has “mainly been in gay, bisexual, and other men who have sex with men without documented history of travel to endemic countries,” the report noted.
On Nov. 6, one more case was detected, taking the total number of clade 1b infected people in the country to four. All four belonged to the same household.
“Mpox is very infectious in households with close contact and so it is not unexpected to see further cases within the same household,” Susan Hopkins, chief medical adviser at the UKHSA, said.
“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.”
The fourth patient has been placed under specialist care. The individual has been in isolation since being identified as a close contact of the first patient.
The UKHSA and partner organizations are following contacts of all infected individuals. When identified, the contacts will be offered testing, vaccination, or further care as necessary, the agency said.
The Oct. 30 clade 1b case was the first time that this variant was detected in the UK. The infected person had traveled recently to African nations that have had a surge in clade 1b infections.
“This includes securing vaccines and equipping healthcare professionals with the guidance and tools they need to respond to cases safely,” he said.
Global Mpox Cases
According to a recent report by the World Health Organization, there were 109,699 confirmed mpox cases across 123 nations between January 2022 and September 2024. The vast majority of the cases are clade 2.As of Nov. 6, more than 2,100 cases of clade 1b had been reported across 11 nations, most of them in Africa. Burundi reported the highest number of infections at 1,726, followed by Uganda with 359, Rwanda with 26, and Kenya with 14. Zimbabwe had two cases and Zambia had one.
Outside of Africa, only eight clade 1b cases have been identified—four in the UK and one each in Sweden, Thailand, India, and Germany.
In Sweden, Thailand, and Germany, the infections were detected in travelers from Africa. In the UK, the initial case was found in a traveler from East Africa. The single case in India was detected in a traveler from the United Arab Emirates.
Clade 2 monkeypox is still circulating “at low levels” in the United States, according to the U.S. Centers for Disease Control and Prevention (CDC), but the agency isn’t aware of any U.S. cases of the clade 1 variant.
“CDC is working with public health partners in the United States and throughout Africa to monitor for mpox cases and increase surveillance capacity, in addition to other activities,” the agency stated.
