MORBILLIVIRUSES IN AQUATIC MAMMALS - REPORT ON ROUND-TABLE DISCUSSION

A workshop was organised to ascertain the current situation with regar d to morbillivirus infections in aquatic animals. The great interest g enerated by the discovery of these new virus infections in 1988 has to some extent abated but much high quality research has continued in th is field as the workshop showed. There is some serological evidence th at the viruses have continued to circulate in most areas since the ini tial epizootics. As to their origin, it appears that the most likely s ource of the European seal morbillivirus (PDV-1) is the North Atlantic and Arctic seal populations. As to the origin of the Mediterranean do lphin morbillivirus and the morbilliviruses isolated from porpoises, t here is serological evidence that the viruses are widespread in many c etacean species in the Atlantic and 93% of long-finned pilot whales (G lobicephala melas) which mass stranded between 1982 and 1993 were morb illivirus seropositive. The epizootic in freshwater seals in Lake Baik al was unrelated to events in the European marine mammal populations. The virus which infected these animals (PDV-2) is indistinguishable fr om canine distemper held strains. Serological and molecular biological studies provided evidence for the presence of the virus in the seals, at least as late as the Summer of 1992 when the animals were last sam pled.