In spring this year, our laboratory confirmed a case malignant catarrhal fever in dead cattle in the Olomouc region. Malignant catarrhal fever is a serious viral disease affecting cattle, bison and deer. The disease is caused by a herpesvirus, most often ovine herpesvirus 2 (OvHV-2). This virus circulates quite normally and unobserved in sheep populations without any clinical signs; however, sheep act as a reservoir for the virus and can infect susceptible ruminant species. Malignant catarrhal fever is often fatal for cattle.
In cattle, the disease is characterised by inflammation, ulceration and exudation of the oral mucosa and mucous membranes of the upper respiratory tract, as well as ocular lesions, nervous system disorders and dermatitis. There is no specific treatment for the disease and no vaccine against the virus. The only preventive measure is to avoid contact between susceptible species and the virus's reservoirs. Contact between cattle and sheep was also the cause of cattle deaths confirmed by our laboratory.