New orthobunyavirus of the Simbu serogroup detected in cattle
On 31 July 2026, the IVI detected the so-called ‘Shamonda-like virus’ in samples taken from cattle with fever, diarrhoea and a drop in milk yield. This is the first occurrence of another virus of the Simbu serogroup in Switzerland since the first Schmallenberg virus outbreak in 2012.
Updates on the evolving situation regarding the Shamonda-like virus in Switzerland :
Update of 17 August 2026: Since the first confirmed case of the Shamonda-like virus in Switzerland, it has been detected in blood samples and several aborted foetuses in 17 cantons and the Principality of Liechtenstein over the past two weeks. The virus continues to spread across Europe. In recent days, it has also been found in the Netherlands.
Update of 13 August 2026: The IVI has also detected the virus for the first time in cattle from Liechtenstein. There is a risk of further spread to the east. The IVI is working closely with the competent laboratory in Austria.
Important information regarding abortion testing: The IVI is unable to test any further foetuses. Please note the information on this page about the sample material to be submitted.
Update of 10 August 2026: analysis of the full viral sequencing of several individual animals from different cantons conducted at the IVI provides conclusive evidence that this is indeed the Shamonda-like virus. The virus is practically identical to the one detected in Germany and also shows only slight differences between individual herds. Further investigations on the exact taxonomic classification of the virus are under way.
Since 6 August 2026, the IVI has, for the first time, detected the Shamonda-like virus in samples from several aborted bovine foetuses from different herds. Other possible causes of the abortions and related factors are currently being investigated. These cases confirm the assumption that the virus can be transmitted transplacentally to bovine foetuses, which may also lead to abortions. The current situation is being closely monitored by the IVI, together with the FSVO, the RGS (organisation for bovine health in Switzerland) and other partners.
Update of 3 August 2026: on 31 July 2026, the IVI detected viruses of the Simbu serogroup in samples from cattle in Switzerland for the first time.
Viruses of the Simbu serogroup – to which the Shamonda virus and Schmallenberg virus belong – mainly occur in Africa, Asia and Australia and, like the bluetongue virus, are transmitted by blood-sucking midges of the genus Culicoides.
It is still not clear whether there is also a connection between the current heatwave and the reported disease occurrences. However, high temperatures place a severe stress on animals, particularly on high-yielding dairy cows, and can make them more susceptible to disease.
Clinical symptoms observed
Nearly all affected cattle farms report a disease lasting around 14–21 days. The most common clinical symptoms are:
- Fever (>40 °C) over 1–2 days
- A huge drop in milk yield
- Loss of appetite
- Diarrhoea
Sample material to be submitted
- Live animal: serum and (optionally) EDTA blood
- Dead adult animal: if possible serum, otherwise spleen and body cavity fluid
- Aborted foetuses: brain, spleen, blood from the heart/body cavity fluid – no placentas, no whole foetuses/whole heads.
Important advice on sample collection:
- In adult animals, virus detection is only feasible in cases of very recent infection. For this reason, samples should, where possible, be taken from animals during the early stages of the disease (fever and/or reduced milk yield) and not only after the onset of diarrhoea.
- If several animals in the herd are affected, send samples from a maximum of three animals.
Cost coverage
The costs of the tests are currently covered by the federal government. However, it is important that:
- details regarding the nature and duration of the symptoms in the animals from which samples were taken are provided on the IVI test application form:
- the questionnaire on symptoms at herd level, drawn up by Rindergesundheit Schweiz (RGS), needs to be completed (German)
Fragebogen “Fieberhafte Durchfallerkrankungen bei Rindern”
Non-specific symptoms such as fever, diarrhoea and a drop in productivity can also indicate a highly infectious animal disease. Animal keepers should therefore notify their vet immediately so that the necessary examinations can be carried out where necessary.
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