The key facts
- The first documented case in history of human infection with the Shamonda virus — a patient with severe immunodeficiency died in early October in Lyon.
- The main hypothesis is transmission through a bite from a Culicoides midge in eastern France, where the virus circulated among animals in spring and summer 2026.
- French authorities, the WHO and the ECDC state that no risk to the population as a whole has been identified; the investigation is ongoing.
First case in a human
The French ministries of health and agriculture reported on 22 October the first documented case of human infection with the Shamonda virus (Shav). The patient, who had a 'severe immunodeficiency' and was being treated for a serious illness at the Hospices Civils de Lyon, died in early October. Previously, the virus, which had circulated in Africa and Asia for decades, was considered non-transmissible to humans. The authorities called the case 'exceptional' and stressed that no risk to public health as a whole has been identified at this time.
Circumstances of the infection
According to the main hypothesis, the patient was infected through a bite from a midge of the genus Culicoides in eastern France, where the virus circulated among animals in spring and summer 2026. According to the ECDC, the specific midge species involved in transmission is not yet known. According to preliminary data from the ministries, the neurological complications observed in the patient before death were 'highly likely' linked to the infection. The newspaper Le Progres reported that the deceased was a man just over 60 who lived in the Lyon area; the head of France's health directorate, Grégory Emery, confirmed that the patient had been hospitalised with an unrelated serious illness. Emery stated: 'We are clearly dealing with a case that is unprecedented from a scientific and virological point of view. It is linked to this man's severely weakened immune system. From a medical point of view and from a public health point of view, there is neither alarm nor a crisis.' He also noted that no cases of transmission from livestock to humans or from human to human have been registered.
Investigation and reaction of international organisations
Clinical, laboratory and epidemiological investigations are continuing jointly with the WHO and the ECDC; the aim is to establish whether the virus caused the death or contributed to it, and how the infection occurred. The WHO said it had not yet conducted an official risk assessment but, based on available data and knowledge of similar diseases, this is an isolated case that is 'unlikely to lead to widespread transmission at present'; the organisation added that transmission of midge-borne viruses usually decreases in the colder months. The ECDC stated that it is working with French and European partners to assess the potential public health consequences.
About the virus and its spread in Europe
The Shamonda virus is a variant of an orthobunyavirus, first identified in Nigeria in the mid-1960s; it had previously been sporadically registered in cattle in West, East and southern Africa, as well as in Japan. It is transmitted by midges and mainly affects cattle — its primary host; cases have also been recorded in sheep, goats, alpacas and horses. In livestock, the virus causes diarrhoea, fever, lethargy, loss of appetite and a drop in milk yields; according to the Belgian institute Sciensano, a significant reduction in milk yields is possible in dairy cows — Reuters reported a fourfold drop in milk yields on infected French farms, and a study of nine French dairy farms showed a reduction of up to 75%. In Europe, the virus was first detected at the end of July based on genomic analyses of sick cows in southern Germany, Switzerland and eastern France. According to the French veterinary bulletin, it has been identified in Austria, Belgium, Ireland, Italy, Liechtenstein, Luxembourg, the Netherlands, Portugal, Slovenia, Spain, Switzerland, Germany, France, as well as on the island of Jersey. The virus is not classified as a disease under EU animal health legislation and is not subject to official surveillance.
Discrepancies between sources
A contradiction has been noted in publications: the outlet Zamon.uz in its Russian- and English-language versions of the article calls the virus the 'Schmallenberg virus', whereas other sources, including the BBC, euronews, Anadolu and Deutsche Welle, are unanimous that the Shamonda virus is meant. Sources also differ on details of the geography of spread: euronews lists 12 countries and Jersey, The National — 11 countries and Jersey (including Slovenia), while Kun.uz, citing the French veterinary bulletin, speaks of 14 countries in Western Europe — from Ireland and Portugal to Austria and Slovenia.
