Sheep-associated malignant catarrhal fever in UK cattle: a case series

Sheep-associated malignant catarrhal fever is caused by ovine herpesvirus 2. Three UK cattle farms had outbreaks of disease with varying pathologies and concentrations of virus detected by quantitative polymerase chain reaction. For Farms 1 and 2, a clear sheep source of infection was identified, but for Case 5 on Farm 3 an obvious source was not found. Subclinical infection was observed in cattle from the same groups on Farms 1 and 2, and latent infection was suspected. Where possible, clinicians should obtain multiple samples for virus detection using molecular techniques and tissue samples from postmortem cases for histopathology.