title: Schmallenberg virus antibody development and decline in a naturally infected dairy cattle herd in Germany, 2011-2014.
abstract: In late 2011, the novel insect-transmitted orthobunyavirus Schmallenberg virus (SBV) emerged in Central Europe. Since that year, a dairy cattle herd kept in the German region in which the virus was initially detected was continuously monitored. In order to evaluate the development of the within-herd seroprevalence, but also to assess the long-term persistence of antibodies against SBV in individual animals, blood samples of all cows older than 24 months were taken yearly after the respective vector season and serologically analyzed. In December 2011, in 74% of the tested animals SBV-specific antibodies were detectable. Additional scattered seroconversions were observed between the 2011 and 2012 vector seasons, thereafter all seronegative animals remained negative. Until December 2014, the intra-herd seroprevalence decreased to 58%. A total of 122 cows infected presumable in autumn 2011 were sampled every year, 9 of them became seronegative until December 2014. Consequently, though SBV-specific antibodies were detected in about 90% of the monitored animals for more than three years, a lifelong antibody-based immunity is not expected in every animal. The loss of anti-SBV antibodies in individual animals combined with the missing infection of young stock results in a declining herd seroprevalence and increases the risk of a renewed virus circulation to a greater extent within the next years.
authors.affiliation: Institute of Diagnostic Virology, Friedrich-Loeffler-Institut (FLI), Greifswald-Insel Riems, Germany.
authors.forename: Kerstin
authors.initials: K
authors.lastname: Wernike
authors.affiliation: Bovine Health Service, Chamber of Agriculture for North Rhine-Westphalia, Bonn, Germany.
authors.forename: Mark
authors.initials: M
authors.lastname: Holsteg
authors.affiliation: State Veterinary Institute Krefeld, Krefeld, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Sasserath
authors.affiliation: Institute of Diagnostic Virology, Friedrich-Loeffler-Institut (FLI), Greifswald-Insel Riems, Germany. Electronic address: martin.beer@fli.bund.de.
authors.forename: Martin
authors.initials: M
authors.lastname: Beer
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood*; D002044:Bunyaviridae Infections / Q000276:immunology / Q000662:veterinary*; D002417:Cattle / Q000276:immunology / Q000821:virology; D002418:Cattle Diseases / Q000276:immunology* / Q000821:virology; D003612:Dairying; D005260:Female; D005858:Germany; D016851:Orthobunyavirus; D012621:Seasons; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral
keywords: Antibody; Immunity; Orthobunyavirus; Persistence; Schmallenberg virus; Serology