Mpox is a spectrum of disease caused by monkeypox virus, which is divided into clades I (with subclades Ia and Ib) and II (with subclades IIa and IIb).1 In 2022, simultaneous detection of non-travel-associated mpox cases in multiple countries was the initial sign that clade IIb was circulating in non-endemic areas, primarily among gay, bisexual, and other men who have sex with men (MSM). Subsequently, WHO declared a public health emergency of international concern (PHEIC). The following year, a new monkeypox virus lineage—clade Ib—emerged in the Democratic Republic of the Congo and spread into neighbouring countries, leading to a second PHEIC being declared.
The Lancet Infectious Diseases published a clinical update in Infectious Disease on 05 Feb 2026.
The item focuses on Circulation of clade Ib mpox outside of Africa—are we prepared?.
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