Malignant catarrhal fever caused by ovine herpesvirus-2 in pigs in Norway

This paper describes the first cases of malignant catarrhal fever (MCF) in pigs in which the diagnosis was verified aetiologically by polymerase chain reaction (PCR) and DNA analysis and by the demonstration of antibodies. Three pigs on two separate premises showed clinical signs, gross pathological and histopathological lesions which were in many respects similar to those of MCF in ruminants. The pigs were housed adjacent to sheep and DNA of ovine herpesvirus-2 (OHV-2) was detected by PCR in tissues of all the pigs. In addition, antibody to alcelaphine herpesvirus-1 was detected in the serum of the pigs and in five in-contact sheep. It is concluded that the disease described is MCF of pigs caused by OHV-2.