UK confirms first Oropouche virus cases in travelers from Brazil

Three British travelers returning from Brazil have tested positive for the Oropouche virus, the first confirmed cases on UK soil, according to new figures from the UK Health Security Agency. The cases, recorded between January and June 2025, come as UK health authorities also report a notable uptick in travel-related chikungunya infections across England, with 73 cases in the first half of the year, the highest total for this period to date. Health officials emphasized that there is currently no vaccine or specific antiviral treatment for Oropouche and stressed preventive measures to reduce bite exposure for travelers.

Oropouche, often nicknamed “sloth fever” because of its wildlife association, is transmitted primarily through bites from midges and certain mosquitoes that have fed on infected animals. The virus is part of the Simbu serogroup of Orthobunyaviruses and, crucially for public health planning, is not known to spread via vectors in the UK or much of Europe. While most infections are mild and self-limiting, symptoms can include fever, severe headaches, joint and muscle pain, fatigue, nausea and a sensitivity to light. In rare cases, the infection can involve the...