French health authorities said on Thursday that Shamonda virus was identified in a human patient for the first time in France. The patient died in October while being treated at Hospices Civils de Lyon for a serious illness, and the French government said the virus had until now been considered non-transmissible to humans.
Officials said the patient already had a weakened immune system. The ministry of agriculture said cerebral complications seen in the patient were very likely linked to the Shamonda infection, while clinical, biological, and epidemiological investigations are still underway.
Lyon and eastern France
The leading hypothesis is that the patient may have been infected in eastern France. That region is where the virus was circulating among animals in spring and summer 2026, and the case links a long-known livestock virus to a human infection for the first time in France.
Shamonda primarily affects livestock, particularly cattle, and it is transmitted by biting midges. The UK Animal and Plant Health Agency said the disease can cause sudden fever, loose stool and abdominal discomfort in adult cattle, and it has documented abortions in infected cattle; infection during pregnancy could result in congenital abnormalities.
Shamonda virus in Europe
Shamonda was first identified in Nigeria in the mid-1960s and has since been detected sporadically in animals in Africa and Japan. The virus was first detected in Germany in August, and Laboklin said it has already been detected in France, Switzerland and Austria.
The virus is an RNA virus in the Simbu serogroup and is genetically related to Schmallenberg virus. There is currently no available vaccine, which leaves livestock surveillance and vector control as the main tools for limiting spread while the investigations continue.
The patient’s case leaves one practical question for farmers and health officials alike: how the infection reached a person after the virus had been treated as non-transmissible to humans. The ministry of agriculture said there is no risk to the general population at this stage, even as the investigation continues in France.
