The pathology and pathogenesis of bluetongue.

摘要: Bluetongue (BT) is an insect-transmitted viral disease of wild and domestic ruminants and, occasionally, other species. Amongst livestock, BT most common in certain breeds sheep whereas asymptomatic virus (BTV) infection cattle typical enzootic regions. can be a feature specific outbreaks, notably the current epizootic Europe caused by BTV serotype 8. replicates within mononuclear phagocytic endothelial cells, lymphocytes possibly cell types lymphoid tissues, lungs, skin tissues. Infected may exhibit prolonged but not persistent viraemia associated with erythrocytes during late stages this viraemia. The pathogenesis involves injury to small blood vessels target relative contributions direct virus-induced cytolysis vasoactive mediators causing dysfunction are presently unclear. lesions characteristic include: haemorrhage ulcers oral cavity upper gastrointestinal tract; necrosis skeletal cardiac muscle; coronitis; subintimal pulmonary artery; oedema ventral subcutis, fascia muscles neck abdominal wall; pericardial, pleural effusions. Transplacental transmission ruminants, subsequent fetal infection, property strains, especially those propagated embryonated eggs or culture. outcome age-dependent, distinctive cavitating central nervous system animals that survive early gestation. Immune competence arises mid-gestation, infected gestation born viraemic without significant brain malformations.