Overview
French health authorities have reported the first known human infection of Shamonda virus in a patient who subsequently died. The case has prompted renewed scrutiny of a virus historically associated with livestock and transmitted by biting midges, now observed in Europe after being identified in other regions decades ago.
What is Shamonda virus?
Shamonda is an insect-transmitted virus carried by biting midges. It predominantly infects cattle, but infections have also been recorded in other domestic animals including sheep, goats, horses and alpacas. The virus is part of the same group as Schmallenberg virus, which is known to cause reproductive problems in farm animals.
Geographic spread
First detected in cattle in Nigeria in 1965, Shamonda has been identified in various parts of Africa and Asia since that time. Its presence in Europe was first noted in late July of this year. By October 20, cases had been reported in over a dozen European countries, including major cattle-producing nations such as France, Germany, Spain and Ireland. French health officials have indicated the virus likely circulated within the country since the spring.
Effects on animals
Clinical signs in affected animals can include fever, diarrhoea and decreased milk yield. More severe outcomes observed in some cases include abortions and significant foetal malformations. In addition, neurological disorders have been reported in some horses infected with the virus. International animal health authorities have noted that the long-term effects of the European virus variants are not yet known.
Risk to humans
The fatal human case in France occurred in a patient receiving hospital treatment for a serious illness who also had a severely weakened immune system. French investigators suspect the person was bitten by a midge in eastern France, an area where the virus had circulated among livestock earlier in the year. Authorities have said the patient’s brain complications were very likely linked to Shamonda, though formal investigations into the infection and cause of death are still ongoing.
The World Health Organization has indicated that, given current information and what is known about related viruses, this appears to be an isolated human case and is unlikely at present to cause broader human spread.
Surveillance and reporting
Shamonda is not listed as a disease by the World Organisation for Animal Health (WOAH), and, as a result, countries are not obligated under WOAH’s disease-specific reporting rules to notify the organisation of cases. The virus is also not included in the European Union’s Animal Health Law framework, meaning it is not subject to EU-level mandatory surveillance that applies to some other animal diseases. Because of these reporting limitations, available data may not capture the full extent of the virus’s distribution.
Current status and uncertainties
Authorities continue to investigate the human infection and monitor the virus’s spread among livestock. Official statements emphasize uncertainty about the long-term impact of the virus variants detected in Europe and note that reporting gaps can obscure the full epidemiological picture.
This report synthesizes available statements and observations from health and animal health authorities regarding the detection of Shamonda virus and its known impacts on animals and the single documented human case.