First known human case of Shamonda virus confirmed in France

France has reported the first ever human case of Shamonda virus, a disease that had so far only affected animals, in a patient that died in early October.

The patient was severely immunocompromized and had been receiving treatment for a serious illness that made them more susceptible to infection and complications, the country’s agriculture, food and health authorities said Thursday.

Brain complications observed in the patient before their death "would most likely be linked to the infection with the Shamonda virus," the authorities said.

They added that this is “an exceptional case in a highly immunocompromized patient,” and that there is “no health risk for the general population.”

Health authorities have highlighted the potential of zoonotic spillover — or the jump of diseases from animals to humans — being behind the next pandemic. Currently, over 60% of emerging infectious disease threats are of zoonotic origin, including Covid-19 and Ebola. As diseases adapt and jump from wild animals to pets to humans, their potential for pandemic threats evolves too. For this reason, scientists have been on high alert for the bird flu.

The Shamonda virus, which spreads between animals through bites from infected midges, was detected in European farm animals for the first time this year. It had previously been found only in countries outside Europe, predominantly in Africa. It is mainly observed in cattle, but there have been cases of infections in horses, sheep, goats and an alpaca.

Since the summer, the virus has been detected in farm animals in Austria, Belgium, France, Germany, Ireland, Italy, Liechtenstein, Luxembourg, the Netherlands, Portugal, Spain and Switzerland, the European Centre for Disease Prevention and Control said. In cattle, its symptoms include fever, diarrhea, lethargy, reduced milk production and mild respiratory signs.

It's still not clear whether the virus caused or contributed to the patient’s death and how the infection was acquired, the ECDC said. French authorities said they believe the patient might have been infected by a midge bite while in eastern France, an area where the virus has been circulating in animals since the spring.

The ECDC said it is “carefully monitoring the situation” and is in touch with French authorities and European partners to “investigate the potential public health implications of this first human infection.”