France reports first known human case of Shamonda virus

French authorities have reported the first known human infection with Shamonda virus, an insect-borne virus previously detected only in animals. The virus was found in a severely immunocompromised patient who was being treated for a serious illness at a Lyon hospital and died in early October.

Authorities said investigations were continuing to determine whether the infection caused or contributed to the patient’s death and how it was acquired. The leading hypothesis is that the patient was infected through the bite of a Culicoides midge in eastern France, where Shamonda virus circulated among animals during the spring and summer of 2026.

France’s health and agriculture ministries said no health risk to the general public had been identified and described the infection as an exceptional case. The World Health Organization told Reuters that, based on current information and knowledge of related viruses, the isolated case was unlikely to lead to wider spread. There is no evidence of sustained human-to-human transmission.

Shamonda virus is an orthobunyavirus that primarily affects livestock, particularly cattle, and is transmitted by biting midges. First identified in Nigeria in the 1960s, it had previously been reported in parts of Africa and Asia. It was confirmed in Europe for the first time in July 2026 and has since been detected in farm animals in several European countries. French authorities have notified the WHO and the European Centre for Disease Prevention and Control, while clinical, biological and epidemiological inquiries continue.