In less than two months, Shamonda-Europe virus has spread widely across western and central Europe. Initially detected mainly in cattle with fever, diarrhoea and reduced milk production, the emerging orthobunyavirus has now been identified in several animal species and an increasing number of European countries. The latest findings are also changing the perception of its potential impact: fetal infections, abortions and congenital abnormalities are shifting surveillance towards the consequences of infection during pregnancy.
As of 26 September 2026, Shamonda virus circulation has been documented in France, Germany, Switzerland, Belgium, the Netherlands, Luxembourg, Austria, Liechtenstein, Italy and Spain. On 24 September, its detection in Jersey also confirmed the presence of the virus in the British Isles. The UK Animal and Plant Health Agency detected the virus in cattle showing clinical signs consistent with those reported elsewhere in Europe.
The geographical expansion has been accompanied by a better understanding of the virus itself. Two genetically distinct variants, SHAV-EU1 and SHAV-EU2, are now recognised in Europe. Analyses conducted by Germany’s Friedrich-Loeffler-Institut indicate that the current situation probably reflects at least two separate introduction and spread events rather than the expansion of a single European strain.
France: extensive circulation and the first congenital cases in sheep
France remains one of the European countries where Shamonda circulation has been most extensively documented.
By late September, the virus had been identified in cattle across a large part of the country, with the geographical distribution continuing to expand westwards and southwards during September.
The most significant development, however, concerns small ruminants. A first French ovine outbreak associated with congenital abnormalities was reported in the Oise department. Affected lambs showed abnormalities including arthrogryposis and brachygnathia, and viral RNA was detected in brain tissue.
The finding provides further evidence that maternal infection can lead to transplacental transmission and that the consequences of infection may only become apparent several weeks or months later.
French surveillance is therefore increasingly moving beyond the acute febrile and diarrhoeic syndrome observed in adult cattle towards reproductive disorders, abortions and congenital abnormalities.
Switzerland: surveillance increasingly focused on abortions and newborn animals
Switzerland played a central role in the identification of the European emergence.
The Swiss Institute of Virology and Immunology identified Shamonda virus on 31 July 2026 in cattle presenting with fever, diarrhoea and reduced milk production. Viral material was subsequently detected in aborted bovine fetuses from several herds.
These observations support the possibility of transplacental transmission and an association between maternal infection and pregnancy losses.
Swiss surveillance is consequently being redirected. From October, testing will focus primarily on abortions, weak newborn animals and animals displaying congenital abnormalities, as acute infections in adults are expected to decline with the end of the vector season.
Switzerland has also provided one of the first indications that the host and clinical spectrum may be broader than initially suspected. The virus was detected in brain samples from horses with central nervous system disorders, although additional investigations are required to clarify the causal relationship.
Germany: two variants and several susceptible species
Germany has been instrumental in characterising the genetic diversity of the European outbreak.
The variant initially identified in southern Germany, Switzerland and France is now designated SHAV-EU1. Sequence analysis of positive cattle samples from north-western and eastern Germany subsequently revealed a second genetically distinct variant, SHAV-EU2. Differences were identified in all three genome segments.
The Friedrich-Loeffler-Institut considers these findings consistent with two independent introduction and spread events that are now overlapping geographically.
The host range has also widened. In addition to cattle, SHAV-EU1 infections have been identified in sheep, goats and horses. Germany has also reported infection in an alpaca.
A horse presenting with severe neurological signs was found to carry a high viral load in brain tissue. The finding is of particular interest, although the clinical significance of equine infection remains under investigation.
Belgium: fetal bovine infections confirmed in Wallonia
Belgium has provided some of the most important new information reported during the second half of September.
By 23 September, more than 250 Walloon herds had submitted samples following suspected infection, and Shamonda-Europe virus had been confirmed in 52 herds, according to ARSIA.
More importantly, the virus has now been detected in aborted bovine fetuses in Wallonia. These findings confirm that fetal infection can occur when the dam becomes infected during pregnancy.
Potential consequences include abortion, stillbirth, congenital abnormalities such as arthrogryposis, central nervous system lesions and the birth of weak calves with neurological or locomotor disorders. The exact gestational periods associated with the highest risk have yet to be established.
ARSIA has also validated a new Simbu PCR kit capable of simultaneously detecting both Shamonda-Europe variants identified in Wallonia and Schmallenberg virus.
The Netherlands: both variants are circulating
The Netherlands is another important area for understanding the European epidemiology of Shamonda virus.
Both SHAV-EU1 and SHAV-EU2 have been identified in Dutch cattle. The coexistence of the two variants confirms that the European circulation patterns are now overlapping.
The virus has also been detected in a newborn calf showing congenital abnormalities. The observation is compatible with intrauterine infection, although detection of the virus alone does not establish that Shamonda was responsible for all of the abnormalities observed.
The Dutch findings nevertheless add to the growing evidence from France, Switzerland and Belgium that the impact of infection during pregnancy may become one of the major veterinary consequences of the 2026 episode.
Luxembourg: widespread circulation and both variants detected
Luxembourg confirmed Shamonda virus in late August.
By 15 September, the virus had been detected in 24 of 41 holdings investigated following suspicion, while 72 of 102 individually sampled animals were positive. The Luxembourg authorities described the geographical distribution as relatively homogeneous across the country.
SHAV-EU1 is the predominant variant, although SHAV-EU2 has also been identified occasionally.
At that stage, most affected cattle had experienced relatively mild disease characterised by fever, diarrhoea and reduced milk production. No abortions or congenital abnormalities attributed to Shamonda had yet been reported in Luxembourg, although surveillance of aborted fetuses was being encouraged.
Austria: SHAV-EU1 continues to expand
Shamonda virus was first detected in Austrian cattle during the summer and subsequently spread across several federal states.
The Austrian situation appears to be dominated by SHAV-EU1, the variant also widely detected in southern Germany, Switzerland and France.
As elsewhere in Europe, the absence of mandatory harmonised notification makes it difficult to establish the true number of infected herds. Veterinary guidance has increasingly focused on the possible consequences of infection during pregnancy, including abortion and congenital abnormalities.
Liechtenstein: infection confirmed early in the European wave
Liechtenstein confirmed Shamonda infection in cattle in August, shortly after the first Swiss detections.
Its location between Switzerland and Austria made the finding one of the early indications that transmission was extending beyond the initial French-German-Swiss area.
The virus detected in this region belongs to the SHAV-EU1 group.
Italy: first infections confirmed in northern dairy herds
Italy confirmed Shamonda virus circulation during August.
The first official Italian cases were confirmed on 31 August in dairy cattle herds in the provinces of Trento and Bolzano, as well as in some cattle introduced into Italy from France.
Affected cattle presented with the clinical pattern already reported elsewhere in Europe, predominantly fever, diarrhoea and a marked decrease in milk production. Abortive events have also been associated with infection.
Shamonda infection is not currently a listed disease under EU animal health legislation and is therefore not subject to compulsory notification or specific official control measures in Italy.
Spain: SHAV-EU1 reaches the Iberian Peninsula
Spain is among the most recently affected European countries.
The Spanish Central Veterinary Laboratory in Algete confirmed SHAV-EU1 in cattle herds in September. The animals showed the same clinical syndrome reported elsewhere in Europe: fever, diarrhoea and reduced milk production.
Spanish veterinary authorities describe cattle as the main species in which clinical disease has so far been characterised. Sheep and goats are also susceptible to infection, while positive horses with neurological disease have been reported elsewhere in Europe, although a causal association has not yet been definitively established.
The Spanish detections significantly extend the known circulation area of the virus into the Iberian Peninsula.
Jersey: Shamonda reaches the British Isles
The most recent major geographical development concerns Jersey.
On 24 September, the UK Animal and Plant Health Agency announced that Shamonda virus had been detected in cattle on the island. Samples had been collected in August from animals showing clinical signs consistent with those reported in continental Europe.
The finding confirms the presence of Shamonda virus in the British Isles and places it in close proximity to Great Britain.
APHA also notes that abortions have been documented in infected cattle and that infection during pregnancy raises concern over congenital abnormalities similar to those associated with Schmallenberg virus and related Simbu serogroup viruses.
Portugal strengthens surveillance but has not confirmed a national outbreak
Portugal has also responded to the rapid European expansion.
On 24 September, the Portuguese Directorate-General for Food and Veterinary Affairs called for increased clinical surveillance and reporting of suspected cases, noting that Shamonda virus had already been detected in several EU countries.
The official Portuguese information available at that date did not report a confirmed autochthonous outbreak in Portugal. The country therefore remains under heightened surveillance rather than being classified among those with confirmed circulation.
Surveillance is moving from acute disease towards pregnancy outcomes
Two months after Shamonda virus was first identified in central Europe, the epidemiological picture has changed considerably.
In adult cattle, infection is still primarily associated with an acute and generally transient syndrome characterised by fever, diarrhoea, lethargy and reduced milk production. Most adult animals appear to recover.
The key development in September has been the accumulation of evidence concerning infection during pregnancy.
Shamonda virus has been identified in aborted bovine fetuses in Switzerland and Belgium. Congenitally abnormal lambs have been reported in France, while a malformed newborn calf in the Netherlands was also virus-positive.
These observations are biologically consistent with the behaviour of other Simbu serogroup orthobunyaviruses, particularly Schmallenberg and Akabane viruses, which can cross the placenta and interfere with fetal development. Spanish veterinary authorities also recognise the possibility of vertical transmission during pregnancy.
However, major uncertainties remain. The frequency of fetal infection is still unknown, as are the gestational stages associated with the greatest risk and the overall proportion of abortions or congenital abnormalities attributable to Shamonda infection.
The seasonal decline in Culicoides activity should progressively reduce new vector-borne infections during the autumn. It will not necessarily mark the end of the 2026 episode.
The consequences of infections acquired during the summer may only become apparent weeks or months later, when affected pregnancies end in abortion, stillbirth or the birth of malformed offspring.
The autumn and winter of 2026-2027 will therefore be critical for determining the true reproductive impact of Shamonda-Europe virus and for establishing whether SHAV-EU1 and SHAV-EU2 differ in their ability to cause fetal infection or congenital disease.
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