French health authorities are investigating the first recognised human infection with Shamonda virus, a midge-borne pathogen previously identified in animals. The case involved a man with serious underlying health conditions and a weakened immune system who died earlier this month.
The European Centre for Disease Prevention and Control (ECDC) has confirmed the detection but said it remains unclear whether the virus caused or contributed to the patient’s death. Investigations are continuing to determine the circumstances of infection and its possible role in the patient’s clinical condition.
Virus Previously Identified in Livestock
Shamonda virus belongs to the bunyavirus group and is primarily transmitted through bites from infected midges. It has been detected in several animal species, including cattle, sheep, goats, horses and alpacas.
According to the Austrian Agency for Health and Food Safety, infection in livestock can lead to diarrhoea, reduced appetite, decreased milk production, abortions and congenital abnormalities in newborn animals.
Viral genetic material has also been identified in the brains of horses in Switzerland and Germany that died after developing neurological symptoms.
Although Shamonda virus has circulated in animals outside Europe for years, its detection in European livestock was reported for the first time during the summer of 2026.
Health Authorities Examine Neurological Complications
The French patient reportedly experienced neurological complications, raising questions about whether the infection contributed to his illness.
Professor Tom Solomon, Director of the Pandemic Institute at the University of Liverpool, said French authorities considered the neurological complications very likely to be associated with the infection, although further investigations were necessary.
He noted that several aspects of the virus remain poorly understood, including whether healthy individuals can develop asymptomatic infections, what symptoms human infection may produce and how frequently severe illness might occur.
Experts Assess Risk to General Population as Low
Despite the detection, infectious disease specialists have indicated that the immediate risk to the wider population appears limited.
Professor Solomon said the identification of only one recognised human infection despite years of viral circulation in animals suggests that transmission to humans is extremely uncommon.
Dr Ben Brennan of the MRC-University of Glasgow Centre for Virus Research also stated that there is currently no evidence of sustained human-to-human transmission.
He emphasised that the finding requires further scientific investigation and surveillance but does not presently indicate a significant new public health threat.
Further Surveillance and Research Needed
The ECDC and French authorities are continuing their assessment of the case to establish how the patient acquired the infection and whether Shamonda virus contributed to his death.
The detection highlights the importance of monitoring animal-borne viruses and investigating their potential to infect humans.
For now, experts say the single reported case does not establish a broader outbreak risk, and there is no evidence suggesting that the general public needs to adopt additional precautions.