Bovine Respiratory Coronavirus

Bovine coronaviruses (BCoVs) cause respiratory and enteric infections in cattle and wild ruminants. BCoV is a pneumoenteric virus that infects the upper and lower respiratory tract and intestine. It is shed in feces and nasal secretions and also infects the lung. BCoV is the cause of 3 distinct clinical syndromes in cattle: (1) calf diarrhea, (2) winter dysentery with hemorrhagic diarrhea in adults, and (3) respiratory infections in cattle of various ages including the bovine respiratory disease complex or shipping fever of feedlot cattle. No consistent antigenic or genetic markers have been identified to discriminate BCoVs from the different clinical syndromes. At present, there are no BCoV vaccines to prevent respiratory BCoV infections in cattle, and the correlates of immunity to respiratory BCoV infections are unknown. This article focuses on respiratory BCoV infections including viral characteristics; epidemiology and interspecies transmission; diagnosis, pathogenesis, and clinical signs; and immunity and vaccines.