Fatal Interstitial Pneumonia Associated with Bovine Coronavirus in Cows from Southern Italy.

An outbreak of winter dysentery, complicated by severe respiratory syndrome, occurred in January 2020 in a high production dairy cow herd located in a hilly area of the Calabria region. Of the 52 animals belonging to the farm, 5 (9.6%) died with severe respiratory distress, death occurring 3-4 days after the appearance of the respiratory signs (caught and gasping breath). Microbiological analysis revealed absence of pathogenic bacteria whilst Real-time PCR identified the presence of RNA from Bovine Coronavirus (BCoV) in several organs: lungs, small intestine (jejunum), mediastinal lymph nodes, liver and placenta. BCoV was therefore hypothesized to play a role in the lethal pulmonary infection. Like the other CoVs, BCoV is able to cause different syndromes. Its role in calf diarrhea and in mild respiratory disease is well known: we report instead the involvement of this virus in a severe and fatal respiratory disorder, with symptoms and disease evolution resembling those of Severe Acute Respiratory Syndromes (SARS).