French health authorities have reported the first known human case of Shamonda virus, an insect-borne infection normally found in livestock, after the virus was detected in a patient who subsequently died.

Officials said there was no evidence at this stage that the virus poses a threat to the general population.

Shamonda virus primarily affects animals, particularly cattle, and is transmitted through the bites of small insects known as Culicoides midges.

According to a joint statement from France’s health and agriculture ministries, the patient was severely immunocompromised and had been hospitalised in Lyon for a serious underlying illness. The patient died in early October.

“Despite several decades of circulation of the Shamonda virus in Africa and Asia, no human cases had been reported until now,” the ministries said.

They described the infection as an exceptional case involving a patient with a severely weakened immune system.

How the patient may have become infected

Authorities believe the patient may have contracted the virus through the bite of an infected Culicoides midge in eastern France, where the virus had been circulating among animals during the spring and summer.

Investigations conducted so far suggest that neurological complications observed in the patient before death were probably linked to the Shamonda virus infection, according to the ministries.

However, officials have not established that the virus was the sole cause of death, given the patient’s serious underlying medical condition.

The ministries stressed that the case appeared to be highly unusual and that current scientific knowledge did not suggest a wider public health threat.

“Based on what is currently known about this virus, no risk to the health of the general population has been identified to date,” the statement said.

Investigations continue as WHO and ECDC are notified

Clinical, laboratory and epidemiological investigations remain under way under the One Health approach, which recognises the close relationship between human health, animal health and the environment.

French authorities have informed both the World Health Organisation (WHO) and the European Centre for Disease Prevention and Control (ECDC).

The investigations aim to clarify how the patient became infected, the possible role of the virus in the neurological complications and whether any additional public health measures are necessary.

What is Shamonda virus?

Shamonda virus was first identified in Nigeria in the mid-1960s and has since been detected sporadically in cattle across West, East and Southern Africa, as well as in Japan.

The virus was detected in Europe for the first time during the summer of 2026, including in livestock holdings in France, according to the two ministries.

Cattle are considered the principal hosts among susceptible animal species, although sporadic infections have also been identified in other animals.

During the summer, French authorities recorded cases involving small ruminants, such as sheep and goats, as well as equines.

The discovery of the first known human infection marks a new development in the understanding of the virus, although French officials emphasised that there is currently no indication of a broader threat to human health.