The United Kingdom has reported two additional cases of mpox clade Ib, marking the first confirmed instances of local transmission in the WHO European Region. Both cases occurred in household contacts of a person who had recently returned from several African countries and tested positive for mpox. This development makes these the first local transmissions of mpox clade Ib outside of Africa since the Public Health Emergency of International Concern was reinstated in August 2024. Despite the low overall risk to the public, WHO/Europe has urged countries across the Region to be prepared for swift action in managing mpox transmission.

Dr. Hans Henri P. Kluge, WHO Regional Director for Europe, highlighted that while the general population’s risk remains low, the emergence of local transmission should motivate health systems across the Region to enhance surveillance and be prepared to quickly trace contacts of both confirmed and suspected cases. He also called for supportive environments for individuals who may be infected, urging them to seek testing and care without fear of stigma.

The mpox virus, which primarily spreads through close physical contact, including sexual contact, can also be transmitted via contaminated objects such as bedding or clothing. Although respiratory droplet transmission may occur in close contact settings, it is not a primary route of spread. Preventative measures, particularly for travelers to countries with active outbreaks, include avoiding close skin-to-skin contact with symptomatic individuals, frequent handwashing, and vaccination where available. WHO’s vaccination guidance remains unchanged, with a focus on at-risk groups, including health workers and individuals with multiple sexual partners.

In cases of mpox, health providers guide patients on recovery, which may involve home isolation or hospitalization depending on individual circumstances. Patients isolating at home are advised to take precautions to protect household members, such as staying in separate rooms, avoiding shared personal items, maintaining good ventilation, and promoting frequent handwashing and disinfection.

Mpox clade II previously caused the 2022 outbreak in the WHO European Region, particularly affecting men who have sex with men (MSM). In contrast, mpox clade Ib has been circulating in the Democratic Republic of Congo and has also been reported in nearby countries, with cases exported to various nations, including Sweden, India, Thailand, and Germany. WHO emphasizes the interconnected nature of today’s world, noting that high-risk contacts of infected individuals may occasionally become infected, but such risks can be managed effectively through vigilance.

Dr. Kluge commended the United Kingdom for its swift response to identify and contain the cluster, as well as for its transparent communication to support data sharing and reporting. WHO calls on all Member States in the European Region to enhance surveillance for both mpox clades, reinforce public health guidance, and expand access to vaccines and antiviral treatments, especially for close contacts of infected individuals. WHO also discourages any travel or trade restrictions in response to mpox cases.

Preventing further mpox transmission hinges on measures known to work: effective surveillance, isolation and care of infected individuals, thorough contact tracing, and clear risk communication to counter fear and stigma. Transparent information sharing across countries is critical for a coordinated response. WHO/Europe has offered its support to Member States through the newly established Pan-European Network for Disease Control, chaired by the UK Health Security Agency. According to Dr. Kluge, applying these established measures across the Region will be essential to halting mpox transmission and engaging affected communities.