The UK reported on Tuesday two additional cases of a newly emerging variant of mpox, known as clade 1b, raising the country's total count to three.
The UK Health Security Agency (UKHSA) said in a statement that the cases were identified among household contacts of the first patient, who was diagnosed in London on Oct. 30 after returning from an African nation severely affected by the virus.
Susan Hopkins, chief medical adviser for 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."
She added that while the risk to the broader UK public remains low, efforts are ongoing to trace all contacts of those infected to prevent further transmission.
So far, only a handful of cases of this new variant have been detected in Europe, with reports from Sweden and Germany.
The UKHSA continues to coordinate with health partners to monitor and contain the spread of the virus.
Clade 1b mpox is a new variant that health authorities have flagged as particularly concerning due to its potentially increased severity.
Unlike other mpox strains circulating in the UK since 2022, clade 1b is associated with more severe symptoms and higher risks of complications, particularly for vulnerable populations such as pregnant women.
Mpox symptoms typically include a lumpy rash with pus-filled lesions, fever, muscle aches, and fatigue, with added dangers of miscarriage when contracted during pregnancy.
This strain was initially identified last year in the Democratic Republic of Congo (DRC), where it has infected over 25,000 people and resulted in more than 1,000 fatalities.
The World Health Organization declared mpox a global health emergency earlier this year.
