This epidemiological overview provides an update to the number of confirmed and highly probable mpox clade Ib and clade IIb cases in England, Northern Ireland, Scotland and Wales.

Mpox is a zoonotic infection, caused by the monkeypox virus, that occurs mostly in West and Central Africa. Prior to 2022, cases diagnosed in the UK had been either imported from countries where mpox is endemic or contacts with documented epidemiological links to imported cases. Between 2018 and 2021, there had been 7 cases of mpox in the UK. Of these, 4 were imported, 2 were cases in household contacts, and 1 was a case in a health care worker involved in the care of an imported case. There was no documented community transmission in previous outbreaks. The first case of mpox clade Ib infection was confirmed in the UK on 30 October 2024.

Further background information on mpox clade Ib and clade IIb is available.

Current epidemiological situation of mpox clade Ib up to 31 January 2025

Up to 31 January 2025, 9 cases of mpox clade Ib cases have been reported in the UK. Of these, 9 were in England, 0 in Northern Ireland, 0 were in Scotland and 0 were in Wales. To 31 January 2025, 100% of these cases have direct or indirect links to travel to countries where mpox clade Ib is circulating. More information can be found in the list of Clade I mpox: affected countries.

Figure 1 shows the monthly number of mpox clade Ib cases in England during 2024 and 2025.

Figure 1. Number of mpox clade Ib cases in England, by month in October 2024 to 31 January 2025

Current epidemiological situation of mpox clade IIb up to 31 January 2025

Detection of cases of mpox clade IIb infection, acquired within the UK, were confirmed in England from 6 May 2022. The outbreak has mainly been in gay, bisexual, and other men who have sex with men without documented history of travel to endemic countries.

Up to 31 December 2022, there were 3,732 confirmed and highly probable mpox clade IIb cases reported in the UK. Of these, 3,553 were in England, 34 were in Northern Ireland, 97 were in Scotland and 48 were in Wales.

During the period, 2023 to 2025 (up to 31 January 2025) there have been a total of 452 cases of mpox clade IIb reported in the UK. Of these, 418 were in England (188 cases were presumed to have acquired mpox in the UK, 137 were acquired outside the UK and 93 are awaiting classification), 18 were in Scotland (4 were presumed to have acquired mpox in the UK, 9 were imported cases acquired outside the UK and 5 are awaiting classification), 8 were in Wales (4 were presumed to have acquired mpox in the UK, 2 were imported cases acquired outside the UK and 2 are awaiting classification), and 8 were in Northern Ireland (5 were presumed to have acquired mpox in the UK and 3 were imported cases acquired outside the UK).

Figure 2 shows the monthly number of mpox clade IIb cases in England during the period 2023 to 2025, where there were between 1 and 41 cases per month, compared to the monthly high of 1,339 cases in July 2022.

Figure 2. Number of confirmed and highly probable mpox clade IIb cases in England, by month in 2023 to 2025

Table 1. Number of confirmed and highly probable mpox clade IIb cases by UK nation of residence, 06 May 2022 to 31 January 2025 [note 1]

UK nation	Cases reported in 2022 [note 2]	Cases presumed acquired in the UK in 2023 to 2025	Cases presumed acquired outside the UK (imported) in 2023 to 2025	Cases awaiting classification in 2023 to 2025	Total (2022 to 2025)
England	3,553	188	137	93	3,971
Northern Ireland	34	5	3	0	42
Scotland	97	4	9	5	115
Wales	48	4	2	2	56
Total	3,732	201	151	100	4,184

Note 1: Based on data extracted on 3 February 2025.

Note 2: Figures for 2022 start from 6 May 2022 and combine UK acquired and imported cases.

Data sources

Mpox surveillance data in England is based on mpox and orthopox virus test results from the Rare and Imported Pathogens Laboratory (RIPL), which is the UK Health Security Agency (UKHSA) mpox reference laboratory, and other UK laboratories with mpox and orthopox testing.

Suspected mpox samples that are positive using a mpox polymerase chain reaction (PCR) test is classified as confirmed cases. Samples which are positive using an orthopox PCR test are classified as highly probable cases. Orthopox is the group of viruses which includes mpox. The counts presented in this report combine both of these categories.

Counts of confirmed cases in Wales, Northern Ireland, and Scotland are submitted to UKHSA by Public Health Wales, Public Health Agency Northern Ireland, and Public Health Scotland respectively.

Information about this publication

These figures are used for official reporting of mpox confirmed case counts in the UK.

England counts may differ from those published in the Notifications of infectious diseases (NOIDs) causative agents weekly report. This is due to differences in timings of when the data is compiled, and differences in processing of duplicate data (for example, if a person has tested more than once but insufficient information is provided to identify them).

As mpox continues to be a notifiable infection, please refer to UKHSA’s NOIDs reports for weekly updates (but not cumulative totals) on laboratory-notified mpox cases in England.

While data cleaning is carried out routinely, corrections can be applied between reports, such as updates to patient information and the removal of quality assurance samples from laboratory surveillance systems.

Where data is presented by month, this is based on specimen date.

Additional resources

Mpox outbreak: technical briefings

Mpox: case definitions

Mpox contact tracing guidance: classification of contacts and advice for vaccination and follow-up