VESICULAR STOMATITIS

-The causative virus is a vesiculovirus (family Rhabdoviridae).-The first major occurrence of the disease or ' sore tongue' in horses, cattle.-The reservoir host is unknown. However, biological transmission by blood-feeding Insects.-The virus can be biologically transmitted by black flie (Simulium vittatum) and mechanically by Culicoides spp. flies (Musca domestica, and (M. autumnalis-The incubation period ranges from 2 to 8 days.-The virus circulates in the blood for a short period and then blisters develop, primarily in the oral mucosa but foot and teat lesions also occur.-Excessive salivation is often the first sign of disease. Initially, the lesions appear as a blanched, flattened bump or blister. -These vesicles rupture leaving raw erosions that are painful and preventthe animal from eating. Lameness occurs when the feet are affected. The lesions cover a large part of the tongue, dental pad, or lining of the cheek.These lesions cannot be distinguished from FMD

PATHOGENESIS: Local infection of the mucous membrane of the mouth and the skin around the mouth and coronets is followed by the development of vesicles on the lips, muzzle, tongue, and also on the teats and interdigital clefts. The frequent absence of classical vesicles on the oral mucosa of affected animals in field outbreaks has led to careful examination of the pathogenesis of the mucosal lesions. Even in experimentally produced cases, only 30% of lesions develop as vesicles; the remainder dehydrate development and terminate by eroding as a dry necrotic lesion.Differential Diagnosis: -location of lesions, age and species of animals affected, and the presence or absence of systemic disease.-Definitive diagnosis is made by antibody tests, and by virus isolation.

DIFFERENTIAL DIAGNOSIS:-Because of its case-for-case similarity to FMD, prompt and accurate diagnosis of the disease is essential. In most countries the disease is notifiable.-All species-FMD and other vesicular diseases.-Cattle-Bovine virus diarrhea-Bovine malignant catarrh-Pseudo cowpox.-Horses-Blister beetle toxicosis-Bullous phemigoid-Phenylbutazone toxicity-Grass seed awns.

التشخيصالتفريقي مطلوبفي و مهم جدول

- VS = vesicular stomatitis - FMD = foot and mouth disease - BVD = bovine viral diarrhea- BTV = blue tongue virus- MCF = malignant catarrhal fever- BPS= bovine popular stomatitis