Key Takeaway:
- First human case reported: France confirmed the first documented human infection with Shamonda virus in a severely immunocompromised patient who later died.
- Transmission remains unclear: The virus primarily affects livestock and spreads through infected biting midges; investigators are examining how the patient contracted it.
- Public health risk remains uncertain: Experts urge continued surveillance, noting that one case does not establish human-to-human transmission.
French health authorities have confirmed the first documented human infection with Shamonda virus, a livestock-associated pathogen, after a severely immunocompromised patient died, prompting investigations into transmission and public health risks.
Health officials investigate first human infection
The patient, who was receiving treatment for a serious illness in Lyon, died in early October. Authorities suspect the infection came from a bite by an infected Culicoides midge in eastern France, where the virus circulated among animals during spring and summer.
The case marks a significant development because Shamonda virus was previously known to infect animals, primarily cattle. French authorities are investigating how the infection occurred and whether the virus contributed to the patient’s death.
The European Centre for Disease Prevention and Control said the patient’s underlying illness increased their vulnerability to infection and complications. “Investigations into whether the virus caused or contributed to the patient’s death and how the infection was acquired are ongoing,” the agency said in an Oct. 22 statement.
French officials have notified the World Health Organization and the ECDC as clinical, laboratory and epidemiological investigations continue. Authorities have not identified a broader public health threat based on current knowledge.
Virus spreads among livestock across europe
Shamonda virus belongs to the orthobunyavirus group and was first identified in cattle in Nigeria in 1965. Researchers have since detected it sporadically in animals across parts of Africa and Asia, including Japan.
The virus primarily spreads among animals through bites from infected midges. In cattle, infections can cause fever, diarrhea, and reduced milk production. Infection during pregnancy may also lead to miscarriages or fetal abnormalities.
The virus was detected in European livestock for the first time in 2026, with cases subsequently reported across multiple countries. The ECDC said infections had been identified in farm animals in Austria, Belgium, France, Germany, Ireland, Italy, Liechtenstein, Luxembourg, the Netherlands, Portugal, Spain and Switzerland, as well as Jersey.
The first reported human case has raised questions about the virus’s ability to infect people. However, researchers do not yet know whether this infection indicates a broader change in transmission or represents an exceptionally rare event.
Experts urge caution as investigations continue
Ben Brennan, a professor of virology at the University of Glasgow, said the case requires careful interpretation because the patient had a serious underlying illness.
“This is an important scientific finding. However, it is important to put this into perspective,” Brennan said in comments reported by WIRED and published through the Science Media Centre. He added that researchers do not yet know whether the virus contributed to the patient’s death.
David Roiz, a scientist at Spain’s Institute for Game and Wildlife Research, also cautioned against concluding a single case. He said it was premature to determine the virus’s potential to infect humans and emphasized the importance of continued monitoring.
The WHO is working with French authorities to investigate the infection’s source and assess possible public health implications. WHO Director-General Tedros Adhanom Ghebreyesus said more information is needed to understand how the patient contracted the virus and whether it could spread through other routes.
There is currently no vaccine for the Shamonda virus. Animal disease control relies on measures such as insecticides and repellents to reduce exposure to biting midges.
Health officials say the case warrants surveillance but does not establish that the virus spreads between people. Further investigations will help determine whether the infection poses any additional risk to humans.
