What is Shamonda virus? France reports first known human case in a severely ill patient

French health authorities said Thursday, Oct. 22, that they had detected the first known human infection with Shamonda virus, a midge-borne virus that until now had been seen only in animals. The patient, who was already severely ill, died in early October.

Officials in France and international health agencies stressed that this appears to be an exceptional, isolated case. Here is what is known, and what is not, based on statements from French authorities as reported by the BBC, the European Centre for Disease Prevention and Control (ECDC), the World Health Organization (WHO) and the World Organisation for Animal Health (WOAH).

This article is for general information only and is not medical advice. Anyone with health concerns should talk to a doctor or follow guidance from their local health department.

What is Shamonda virus?

Shamonda virus, sometimes shortened to SHAV, belongs to the Simbu group of viruses and is closely related to Schmallenberg virus, according to WHO and WOAH. It was first isolated from cattle in Nigeria in 1965 and has since been reported in animals in parts of Africa and Asia, including Japan.

It mainly affects cattle, but WOAH says cases have also been reported in sheep, goats, horses and alpacas. Reported signs in animals include:

• fever and diarrhea
• reduced milk production
• reproductive problems, including abortions and fetal malformations
• less commonly, neurological signs, which have been seen in some horses

How does Shamonda virus spread?

It is thought to spread through bites from Culicoides midges, small fly-like insects. WHO says the virus is not known to pass directly from animal to animal, except from a pregnant animal to its fetus. The ECDC says the specific midge species involved is still unknown.

What happened in France?

According to the BBC’s account of the French health and agriculture ministries’ statement, the patient was being treated for a serious illness at a hospital in Lyon and was severely immunocompromised. The patient developed neurological complications that initial findings suggest were “very likely linked” to the virus.

Officials believe the patient was infected through a midge bite in eastern France, where cases had been found in animals. The ministries said that until now the virus “was considered non-transmissible to humans,” despite decades of circulation in Africa and Asia.

The ECDC said investigations are still underway into whether the virus caused or contributed to the patient’s death, and how the infection happened. WOAH likewise said more work is needed to answer both questions.

Is there a risk to the public?

French officials called it “an exceptional case in a severely immunocompromised patient” and said there was currently no risk to the public, the BBC reported.

WHO confirmed it was the first documented human case and said it had not yet made its own formal risk assessment. Based on current information and knowledge of similar diseases, it said the case appeared isolated and “unlikely to lead to wider spread at this time.” Both WHO and the ECDC noted that midge activity, and the spread of midge-borne viruses, generally declines as the weather cools.

Where has Shamonda virus been found in Europe?

The virus is new to Europe this year. Accounts of the timeline differ slightly: WHO says it was first detected in June 2026 in cattle in southern Germany and Switzerland, while the ECDC says clinical signs were reported from June and the virus was identified in late July.

According to the ECDC, it has since been found in farm animals in Austria, Belgium, France, Germany, Ireland, Italy, Liechtenstein, Luxembourg, the Netherlands, Portugal, Spain and Switzerland, as well as Jersey. WOAH says the European outbreaks involve two variants, called SHAV-EU1 and SHAV-EU2, and that their long-term impact cannot yet be determined.

None of the agencies’ statements cited here report cases in the United States.

What are the symptoms in humans?

Very little is known. WHO says that with only one human case, information is limited. In this case, the patient was already seriously ill and developed additional brain-related symptoms that were considered linked to the virus.

Is there a treatment or vaccine?

No. WHO says there are currently no treatments or vaccines for Shamonda virus.

FAQ

Can people catch Shamonda virus from cows? The virus is believed to spread through midge bites, not direct contact. WHO says it is not known to pass directly between animals other than from mother to fetus.

Did Shamonda virus kill the patient in France? That has not been determined. The patient was already severely ill, and investigators are still working out whether the virus caused or contributed to the death.

Should Americans be worried? Health agencies describe the French case as isolated, and the reports cited here do not mention any U.S. cases. Follow official public health guidance for updates.