Schmallenberg: a new virus in European herds
14/02/2012 - Press release
Schmallenberg virus (SBV), a previously unknown virus that was first detected in Germany in the November 2011, now affects large numbers of cattle, sheep and goat farms in northern Europe. France has not been spared: as of 10 February 2012, 94 sheep farms in eighteen départements of northern France were affected.
Scientists consider that contamination dates back to the summer of 2011. At the time, in the Netherlands and Germany, there were dairy cows suffering from severe diarrhoea, along with a fever and lower milk yields, although no known infectious agent or food or environmental cause had been pinpointed.
It was German laboratory that in the autumn of 2011 identified Schmallenberg virus (from the name of the German town near the first foci. Since December, many cases of foetal infections and multiple malformations in lambs and a small number of calves and kids have been seen on farms in the Netherlands, Belgium, Germany, the United Kingdom and France.
Research is on the front line
"This virus of the family Bunyaviridae, genus Orthobunyavirus, is similar to Akabane virus, which causes malformations in ruminants ", explain Dominique Martinez and Thomas Balenghien, researchers at CIRAD. "By analogy with Akabane virus and others in the group, we think it is vector-borne: by Culicoides or mosquitoes. Infection apparently dates back to the summer of 2011, and the virus spread considerably before being detected ", they add.
The ANSES (Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail) has been tasked with assessing the impacts and risks of any spread of the disease, while research operations have been handed over to the RFSA network (Réseau français pour la santé animale). CIRAD, which is a member of the RFSA steering committee, is either head of or a member of several research groups working on Schmallenberg virus, including knowledge of vector competence and epidemiological data for those farms affected in France.
Action sheets have been drafted and made a priority for CIRAD's animal health teams, in support of the RFSA action plan:
- Serological analysis of the virus using immunofluorescence with microplates.
- Searching for the virus using qPCR in Culicoides captured within the surveillance network during the summer of 2011, the vectorial transmission period.
- Implementation of an epidemiological and entomological survey protocol (Culicoides and mosquitoes) with modelling of the speed of diseases spread and the suspected vectors (participation of the European consortium EDENext, coordinated by CIRAD).
Animal health researchers from CIRAD will be at the upcoming Paris International Agricultural Show, from 25 February to 4 March (Porte de Versailles exhibition centre, Hall 3, Aisle C, stand 69).
- Category: Science