French authorities have confirmed the first known human case of the Shamonda virus, detected in a patient who died in early October at a hospital in Lyon.

The French health and agriculture ministries said on Thursday that the case was "exceptional" and involved a severely immunocompromised patient. Officials stressed there is currently no identifiable health risk to the general population.

The patient is believed to have contracted the virus through a midge bite in eastern France, where the virus had been circulating among animals since spring and summer. The patient was being treated for a serious illness and experienced neurological complications considered "very likely linked" to the virus, based on initial findings.

"Until now, the Shamonda virus was considered non-transmissible to humans," the French statement noted, adding that the virus had only been identified in animals "despite decades of circulation of the Shamonda virus in Africa and Asia."

Shamonda virus, also known as Shav, is an orthobunyavirus primarily carried and spread by biting midges of the genus Culicoides. It mainly affects cattle, causing fever, diarrhoea and poor milk production, but cases have also been recorded in sheep, goats, alpacas and horses. Infections in humans were previously unheard of.

The virus was first detected in Nigeria in the 1960s and has since been reported sporadically in East and Southern Africa, as well as Japan.

The first cases of the virus in Europe were confirmed in late July, following genomic tests on sick cattle in southern Germany, Switzerland and eastern France. It has since been detected in farm animals across a growing number of countries, including Austria, Belgium, Germany, Ireland, Italy, Liechtenstein, Luxembourg, the Netherlands, Portugal, Slovenia, Spain and the United Kingdom's Jersey.

The European Centre for Disease Prevention and Control said it was monitoring the situation and working with French and European partners to investigate the "potential public health implications" of the infection. Authorities are still investigating how the virus spread to a human.

"Clinical, biological and epidemiological investigations are continuing in conjunction with expertise in human, animal and environmental health," the French statement added.

The case has also been reported to the World Health Organization.