NUCLEIC-ACID HYBRIDIZATION ANALYSES CONFIRM THE PRESENCE OF A HITHERTO UNKNOWN MORBILLIVIRUS IN MEDITERRANEAN DOLPHINS

In 1990 an epidemic caused by a morbillivirus was noticed among Medite rranean dolphins. RNA was extracted from the tissues of dolphins and f rom cell cultures infected with a corresponding dolphin morbillivirus isolate. By nucleic acid hybridization this RNA was compared to RNA ex tracted from animal tissue or cell cultures infected with canine diste mper virus (CDV), phocine distemper virus (PDV) or measles virus (MV). The presence of morbillivirus RNA in the dolphin tissue was demonstra ted. Morbillivirus N, P, M and F gene mRNAs were detected in the RNA f rom dolphin morbillivirus infected cells. These mRNA species seemed to be of approximately the same size as the corresponding mRNA species o f CDV, PDV and MV. The results of the comparison demonstrated that the dolphin morbillivirus is genetically different from CDV, PDV and MV. No indication of a close relationship between the dolphin isolate and either CDV, PDV or MV was found.