It will have no effect on the food chain. SBV has not been recorded affecting humans, or, based on similar viruses, is it likely to. Infection is only by midge bite, hence no risk to humans from meat. A survey done in Belgium of 500 red and roe carcasses found evidence of SBV antibodies in deer. The defects seen in cattle and sheep probably will happen, but we are unlikely to see it as the offspring will be scavenged. A nice explanation of how roe kids are unlikely to be affected is below. (The placentome is the attachment of the placenta to the uterus)
Because the virus can infect the fetus only after the first placentome has developed and because roe deer embryos remain in diapause until January (7
), it is unlikely that SBV has contaminated many roe deer fetuses. Because 90% of roe deer were already SBV positive in mid-December and because circulating antibodies prevent transplacental passage of the closest phylogenetic relatives of the virus (8
), we suggest that roe deer fetuses were probably not infected. On the contrary, red deer mate in September, and the first functional placentome is established by the end of October (9
); thus, 80% of pregnant red deer were exposed to the emerging virus when placental transfer was possible. Furthermore, 35% of pregnant red deer were infected in November and December, i.e., after establishment of the first placentome and before the fetus was immunocompetent. By extrapolating the rate of transplacental infection among cattle (6
), we determined that 28% of these pregnancies resulted in contamination of the fetus, i.e., 10%, of expected pregnancies. Because unrestricted replication of Simbu-like viruses occurs in the central nervous system of immunologically incompetent ruminant fetuses (1
), which can lead to a typical arthrogryposis/hydranencephaly syndrome, a 10% loss among fawns can be expected in 2012.