Public health officials in England have identified a new, recombinant form of mpox – formerly known as monkeypox – in an individual with recent travel history to Asia. The discovery, announced in February 2026, raises concerns about the evolving nature of the virus and the potential for increased transmission, though experts emphasize that the overall risk remains unchanged. This new variant combines genetic material from two previously circulating strains, clade Ib and clade IIb, marking a significant development in the ongoing global mpox situation.
Mpox, a zoonotic infection caused by the MPXV virus, is most commonly found in West and Central Africa. Whereas previously rare in the UK, cases began to emerge in late 2024, with the first confirmed case of clade Ib infection recorded on October 30th, 2024, according to the UK Health Security Agency (UKHSA report). The identification of this recombinant virus underscores the importance of continued genomic surveillance to track viral evolution and inform public health strategies.
Understanding Mpox Clades and the New Recombinant Strain
Researchers have identified two main clades of the mpox virus currently circulating globally: clade IIb and clade Ib. Clade IIb was responsible for the widespread outbreak in 2022, infecting approximately 114,000 people and causing 220 deaths worldwide. In the United States, cases peaked in the summer of 2022, reaching 11,000 cases per month. This clade is generally considered less severe, with a mortality rate of around 1%. Clade Ib, however, is associated with more serious illness and a significantly higher fatality rate of approximately 10%.
Historically, clade Ib cases were primarily linked to direct animal-to-human transmission in the Democratic Republic of Congo (DRC), often through butchering and consumption of infected animals. However, a new outbreak that began in the DRC in 2023 has demonstrated person-to-person spread, with cases reported among family members and in healthcare settings with inadequate protective equipment. Notably, cases of clade Ib mpox have also been observed in sex workers and transient workers, and, for the first time, through heterosexual sexual contact. Between January and November 2025, over 48,000 cases of clade Ib mpox were reported in Central and Eastern Africa, with approximately 43 cases identified in other countries, including some with no recent travel history to Africa (UN News).
The newly identified recombinant virus in England contains elements of both clade Ib and clade IIb. This recombination is a natural process that occurs when two related viruses infect the same individual and exchange genetic material, creating a new variant. Experts at the UKHSA confirmed the discovery through genomic sequencing, noting that while not unexpected, the emergence of such a variant warrants close monitoring (Virological.org).
Concerns and the Importance of Vaccination
The emergence of a recombinant mpox virus raises concerns about potential challenges in controlling the spread of the disease. Dr. Boghuma Titanji, assistant professor of medicine at Emory University, expressed that this development is precisely what public health officials have feared, stating that increased circulation of mpox provides more opportunities for the virus to recombine and adapt, potentially establishing itself as a persistent human pathogen.
Fortunately, a vaccine, JYNNEOS, is available to protect against both mpox and smallpox. The vaccine is administered in two doses, four weeks apart, and has been shown to reduce the risk of infection and lessen the severity of symptoms. The Centers for Disease Control and Prevention (CDC) currently recommends the mpox vaccine for gay, bisexual, transgender, and other men who have sex with men who have had or anticipate having multiple sexual partners, sexually transmitted infections, anonymous sexual encounters, or engage in sexual activity at commercial venues or large public events (BBC News).
While the new recombinant strain has not yet been detected in the United States, both clade IIb and clade Ib continue to circulate at low levels. Public health officials emphasize the importance of vaccination for eligible individuals to mitigate the risk of infection and further viral evolution.
Disclaimer: This article provides informational content about mpox and should not be considered medical advice. Please consult with a qualified healthcare professional for diagnosis and treatment of any health condition.
The ongoing monitoring of mpox, including genomic surveillance, remains crucial to understanding the virus’s evolution and adapting public health strategies accordingly. Further research will be essential to assess the effectiveness of current vaccines against this new recombinant strain and to inform future vaccine development. Please share this information with your networks and join the conversation in the comments below.
