The emergence of Shamonda virus (SHAV) in Europe this summer was the focus of the FVE webinar on 29 September, bringing together experts from Germany, France and Switzerland to share the latest findings from the field.
Kerstin Wernike (FLI, Germany) explained that the first German cases were reported in late July in cattle with fever, reduced milk production and diarrhoea, with high morbidity. Further investigation identified two European clades, which can be distinguished by PCR: SHAV-EU1, detected first in southern Germany, Switzerland and France, but now also in Austria, Italy, Spain and Portugal, and SHAV-EU2, identified in northern Germany and the Netherlands – and more recently also in north-western France.
Infection in early gestation: abortion, stillbirth and malformations
The virus is transmitted by biting midges and infection in early gestation can result in abortion, stillbirth and foetal malformations. In aborted foetuses, the brain is the best sample tissue for virus isolation. The broader host range of SHAV-EU1, including horses, came as a surprise, the scientists admitted.
Jean-Luc Guérin (ENVT/INRAE, France) described how metagenomic analysis helped identify the virus when initial diagnostic testing for other diseases was negative. Similar findings emerged almost simultaneously in France, Germany and Switzerland, highlighting the value of rapid genomic surveillance and cross-border collaboration.
Short viraemic window: a diagnostic challenge
In Switzerland, Helen Huber (RGS, Switzerland) reported that, to date, 198 cattle had been found positive for SHAV-EU1 on 145 farms. Clinical signs typically follow a sequence of high fever, a drop milk production followed by diarrhoea – by which time the short viraemic window has often already passed. NSAIDs and fluid therapy are used to support infected animals with clinical signs. Eight horses have also tested positive so far.
The experts stressed the importance of timely sampling and information sharing. Real-time detection, metagenomics and international collaboration are essential to understanding this emerging virus.
A replay of the webinar is now available.
(photo ©Paul T./Unsplash)