Switzerland has reported its first case of the new mpox clade Ib strain, joining several European countries already affected. This more dangerous variant was first detected in the Democratic Republic of the Congo (DRC) in 2023 and has since spread across Central Africa, especially in Burundi and Uganda. Health officials in Europe are closely watching the situation, but the public health risk remains low for now.
In August 2024, the World Health Organization (WHO) declared the African mpox outbreak a global health emergency. While most European cases are linked to travel from Africa, experts warn that limited local spread could happen if the virus is not contained.
Where the New Mpox Strain Has Been Detected in Europe
Switzerland Reports First Case Linked to Uganda
In April 2025, Swiss health authorities confirmed the country’s first case of the clade Ib mpox strain. The patient had recently returned from Uganda. Officials stated that the individual is currently in isolation and that there is no immediate threat to the wider public.
United Kingdom Sees Rising Numbers
The United Kingdom has recorded 11 cases so far. Most of these involved travelers returning from Africa. However, one case was reported in a person with no travel history. This has raised concerns about possible local transmission. In response, the UK government has secured over 150,000 vaccine doses and started vaccination campaigns to prevent further spread.
Germany Manages Household Transmission Cases
Germany reported eight cases beginning in October 2024. Most cases involved people who became infected through close contact with travelers. Health officials say there is no evidence of a larger community outbreak at this time.
Belgium Confirms Infections in Travelers and Children
Belgium has confirmed five cases of the clade Ib strain. The first cases were detected in December 2024 and included a traveler and a child. More isolated cases appeared in the following months. Authorities are monitoring the situation but stress that the spread remains limited.
France and Sweden Monitor Isolated Cases
France has reported two cases so far. One patient in Brittany became infected after contact with travelers from Central Africa. Health officials believe more isolated cases could appear, but the risk to the general population is still low.
Sweden was the first European country to detect a clade Ib case outside of Africa. In August 2024, a Swedish traveler returning from Africa tested positive. No additional cases have been reported in Sweden since then.
Health Agencies Stay Alert as New Strain Circulates
Transmission Tied Mainly to Travel
Most of the European cases are still linked to travel from Africa. However, the discovery of a non-travel-related case in the UK shows that limited local transmission could happen. Experts say the new clade Ib strain spreads more easily than previous mpox types.
Children Appear More Vulnerable
Doctors report that the new variant causes more severe illnesses among children compared to earlier strains. Common symptoms include rash, fever, chills, headaches, swollen lymph nodes, and breathing problems. Health authorities are especially cautious when monitoring infections in younger populations.
Public Risk Remains Low, But Vigilance Needed
According to the WHO and national health agencies, the overall public risk in Europe remains low. Even so, experts stress the need for continued monitoring, quick detection, and vaccination readiness. Early action could prevent a wider outbreak if local transmission becomes more common.
Global Efforts to Track and Control the Spread
International health organizations are working together to track the movement of the mpox clade Ib strain. Efforts include information sharing, strengthening local healthcare systems, and supporting vaccination campaigns where needed. Authorities urge travelers returning from Africa to watch for symptoms and seek medical care if they feel unwell.