UK Health Security Agency (UKHSA) told the BBC that the patient had recently travelled to Asia.
Sequencing shows a mix of traits from clade Ib and clade IIb, lineages linked to both Central African outbreaks and the surge that prompted the WHO's emergency declaration last August.
Vaccination guidance and transmission risks
Health agencies have renewed vaccination advice for groups most affected in previous waves.
BBC reporting notes that men who have sex with men and people with multiple partners remain priority groups, although mpox is not classified as a sexually transmitted infection.
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The NHS highlights that close physical contact, contaminated textiles, and prolonged face-to-face exposure can drive spread.
Animal-to-human transmission is also possible through infected fur, blood, or undercooked meat.
Recognising symptoms
Symptoms usually appear within three weeks of exposure.
Early signs often resemble flu-like illness, fever, fatigue, muscle pain, and swollen lymph nodes, followed by a rash that can develop on the hands, feet, mouth, or genital area.
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Some patients may experience anal pain or bleeding. The NHS advises suspected cases to isolate and seek medical guidance promptly.
Sources: Ladbible, BBC, WHO og NHS.
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