Antibodies to Schmallenberg virus in domestic livestock in Turkey

Abstract

This, partly retrospective study, was designed to determine the seroprevalence of Schmallenberg virus (SBV), a new Orthobunyavirus first reported in Germany in late 2011, in domestic ruminants from the Middle Black Sea, West, and Southeast regions of Turkey. An indirect enzyme-linked immunosorbent assay was used to screen serum samples collected from slaughterhouse animals between 2006 and 2013. The overall seroprevalence was 335/1,362 (24.5 %) with 325/816 (39.8 %), 5/307 (1.6 %), 3/109 (2.8 %), and 2/130 (1.5 %) recorded in cattle, sheep, goats, and Anatolian water buffalo, respectively. This is the first study to demonstrate the presence of antibodies to SBV in Turkish ruminants; it indicates that cattle are more susceptible to infection than sheep, goats, or buffalo and that exposure of domestic ruminants to SBV in Turkey may have occurred up to 5 years prior to the first recorded outbreak of the disease in 2011.

A review on Schmallenberg virus infection: a newly emerging disease of cattle, sheep and goats

“…However, in sheep and goats SBV infection is almost asymptomatic with transplacental transmission to foetuses in pregnant animals, causing abortions, stillbirths and a variety of congenital malformations mainly involving the skeletal and nervous systems. Initially, the disease was confined to Northern and Western Europe; however, the detection of SBV antibodies in cattle, sheep, goats and buffaloes (between 2006 and 2013) in a retrospective study in Turkey (Azkur et al 2013) not only indicates the presence of virus prior to its detection in 2011 in Germany, but also harbingers its spread to Eastern European countries, although the presence of SBV in vector insects in Turkey has not yet been confirmed. As Culicodes midges can spread infection across national borders (De Regge et al 2012;Rasmussen et al 2012;Veronesi et al 2013), this may not augur well for landlocked Eastern European and Asian countries which already harbour species of these vectors responsible for dissemination of Akabane and bluetongue viruses in these regions.…”

“…SBV has been isolated or confirmed by PCR in cattle, sheep, goat, bison roe deer and red deer, whereas the serological presence of SBV antibodies has been detected in roe deer, red deer, alpaca (new-world camelids), mouflons and water buffalo (Azkur et al 2013;Conraths et al 2013). According to the current data, infection with SBV is more efficient in sheep than in cattle (FLI 2013a).…”

“…In Belgium, a serological survey of 1082 sheep and 142 goats to detect SBV-specific antibodies by ELISA revealed a 98.03% overall between-herd seroprevalence in sheep and a 40.68% within-herd seroprevalence in goats (Meroc et al 2013b). So far, infections with SBV have been detected in Germany, the Netherlands, Belgium, the United Kingdom, France, Italy, Luxembourg, Spain, Denmark, Estonia, Switzerland, Ireland, Northern Ireland, Norway, Sweden, Finland, Poland, Austria, Switzerland and Turkey (Elbers et al 2012;Azkur et al 2013;FLI 2013a;Larska et al 2013;Meroc et al 2013a,b;Sailleau et al 2013). According to unconfirmed reports there could be infection in further European countries.…”

“…Similarly, in United Kingdom, 1753 animals comprising 1257 cattle, 492 sheep and two goats, one red deer and one alpaca have tested positive for SBV as of 24 th April, 2013(AHVLA, 2013. In a retrospective study in Turkey, employing indirect ELISA to screen 1362 serum samples collected from slaughterhouse animals between 2006 and 2013, the overall seroprevalence for SBV infection was found to be 24.5%, comprising 39.8% cattle, 1.6% sheep, 2.8% goats and 1.5% Anatolian water buffaloes, which indicated that the exposure of domestic ruminants to SBV in Turkey may have occurred up to five years prior to the first recorded outbreak of the disease in 2011 (Azkur et al 2013). In Belgium, a serological survey of 1082 sheep and 142 goats to detect SBV-specific antibodies by ELISA revealed a 98.03% overall between-herd seroprevalence in sheep and a 40.68% within-herd seroprevalence in goats (Meroc et al 2013b).…”

“…Field evidence from Europe shows that many animals are infected with SBV without any clinical signs (DEFRA 2013). Typically, the impact in most affected herds or flocks has been low, although a small number of farms have reported more significant losses (DEFRA 2013;FLI 2013a;Azkur et al 2013;Larska et al 2013;Meroc et al 2013a,b).…”