Human Transmission of Mpox Clade 1b Confirmed in Spain

Spain's health officials have reported what appears to be the first case of human-to-human transmission of the mpox clade 1B outside of Africa.

This case was published in the International Journal of Infectious Diseases (Volume 163108224, February 2026) and describes a 49-year-old man who visited a clinic in Madrid in October 2025.

Researchers noted that vulnerable groups, particularly men who have sex with men, are mainly affected by this virus. They also emphasized the need for preparedness for potential local transmission outside of African regions, as the zoonotic infectious disease caused by the Mpox virus may spread further.

This is the second case of mpox clade Ib in Spain; however, the first one was in a patient with a travel history.

The global mpox outbreak was first recorded in May 2022, with cases linked to travelers from the Canary Islands and Spain.

According to data, Spain has reported over 9,000 mpox cases, with 487 in 2025.

Since August 2024, the World Health Organization has declared Mpox a Public Health Emergency of International Concern due to the risk of international spread of clade Ib. As of December 8, 2025, the WHO stated that all clades of the monkeypox virus continue to circulate.

The U.S. CDC reported in December 2025 that there had been more than 46,000 cases of clade I mpox in several countries in Central and Eastern Africa.

According to the WHO and the CDC, mpox is a vaccine-preventable disease. Getting both recommended JYNNEOS® (MVA-BN®, IMVAMUNE®) doses provides the best protection against the monkeypox virus.

Mpox vaccination services are offered in the United States at health departments and travel clinics.