Dose-dependent effect of experimental Schmallenberg virus infection in sheep

Three Different Routes of Inoculation for Experimental Infection with Schmallenberg Virus in Sheep

“…Thus, the lack of infection is most likely not related to the ID route itself and could be related to a random failure of infection or individual factors of resistance. The observed RNAemia (Figs a and b), in both SC and ID groups, was comparable in duration (3–5 days) and in line with previous data (Hoffmann et al., ; Wernike et al., ; Poskin et al., ) following IV and SC inoculations. The mean SBV genome copy numbers detected in the blood of sheep with RNAemia were not significantly different between SC and ID groups through time (two‐way anova with repeated measures; group effect: P = 0.15; group–time interaction: P = 0.41).…”

“…Seroconversion occurred between 6 and 8 dpi in SC and ID groups (Figs e and f). As previously reported, the decrease of SBV RNA in the blood correlated with seroconversion (Poskin et al., ). However, as the animals were only tested for 10 days, a later seroconversion might have been possible in ewes without RNAemia.…”

“…The extraction of RNA from organs, faeces and serum, and the detection of SBV S‐segment by a one‐step reverse‐transcription (RT) quantitative PCR (RT‐qPCR) were performed as described previously (De Regge et al., ). The quantification cycle (Cq) values were converted into copy numbers (Poskin et al., ), and results were included only when negative extraction controls and negative and positive amplification controls were satisfactory.…”

Schmallenberg virus detection in Culicoides biting midges in Spain: First laboratory evidence for highly efficient infection of Culicoides of the Obsoletus complex and Culicoides imicola

“…The transmission cycle of SBV seems to be ephemeral at individual herd level. This would result from interaction of two factors influencing SBV transmission dynamics: short viremia in hosts (Poskin et al., ; Wernike, Eschbaumer, Breithaupt, Hoffmann, & Beer, ) and early appearance of long‐lasting host immunity (Poskin et al., ). However, the disease spread rapidly from North to South Europe suggesting either, rapid movement of host and/or vectors or/and a high SBV infection (see Table ) and transmission rates for certain Culicoides species.…”

Serological Study of Exposure to Selected Arthropod-Borne Pathogens in European Bison (Bison bonasus) in Poland

“…The wallows created by American bison and filled with water and waste are preferentially colonized by C. sonorensis and C. variipennis, North American vectors of such arboviruses as BTV and EHDV in (Pfannenstiel and Ruder, 2015). In case of domestic ruminants, SBV seroprevalence was also higher in cattle than in small ruminants (Larska et al, 2014a), which may be explained by the lower dose of SBV necessary to produce an infection in bovids comparing to sheep, which would need a 10-fold virus dose to seroconvert (Wernike et al, 2012;Poskin et al, 2014). Furthermore, larger hosts excrete more carbon dioxide and 1-octen-3-ol, the volatile attractants for haematophagous midges, which may increase the risk of the exposure to vector-borne pathogens (Koch and Axtell, 1979;Zimmer et al, 2015).…”