Overwintering mechanism for bluetongue virus: biological recovery of latent virus from a bovine by bites of Culicoides variipennis.
Bluetongue virus (BTV) was biologically transmitted by the bites of colonized Culicoides variipennis gnats to recipient sheep from a Hereford bull with latent infection. Four biological recoveries of BTV were mediated over 2 years by multiple feedings of the vector during a 4- to 72-hour interval. Initial stimulation by gnat bites at 0 hour permitted biological recovery of BTV by gnats that fed at later intervals. The 4th biological recovery of the virus from the bull clearly indicated a vector-mediated viral recovery mechanism in which initial vector bites at 0 hours stimulated a "showering" of BTV into the blood stream of the bull. The BTV carrier bull developed no overt signs of illness during these studies. The pertinent BTV assay and serologic results for the 4 1/3 years of the bull's life are summarized in this report.
D000818:Animals; D001819:Bluetongue / Q000382:microbiology / Q000635:transmission; D001820:Bluetongue virus / Q000302:isolation & purification*; D002417:Cattle / Q000382:microbiology; D002519:Ceratopogonidae / Q000382:microbiology*; D004199:Disease Vectors; D008297:Male; D012087:Reoviridae / Q000302:isolation & purification*; D012621:Seasons; D012756:Sheep / Q000382:microbiology