''Phocine morbillivirus'', formerly ''phocine distemper virus'' (PDV), is a
paramyxovirus of the genus ''
Morbillivirus
''Morbillivirus'' is a genus of viruses in the order '' Mononegavirales'', in the family '' Paramyxoviridae''. Humans, dogs, cats, cattle, seals, and cetaceans serve as natural hosts. This genus includes seven species. Diseases in humans associa ...
'' that is pathogenic for
pinniped
Pinnipeds (pronounced ), commonly known as seals, are a widely range (biology), distributed and diverse clade of carnivorous, fin-footed, semiaquatic, mostly marine mammal, marine mammals. They comprise the extant taxon, extant family (biology ...
species, particularly seals.
Clinical signs include laboured breathing, fever and nervous symptoms.
PDV was first identified in 1988 as the cause of death of 18,000
harbor seal
The harbor (or harbour) seal (''Phoca vitulina''), also known as the common seal, is a true seal found along temperate and Arctic marine coastlines of the Northern Hemisphere. The most widely distributed species of pinniped (walruses, eared se ...
s (''Phoca vitulina'') and 300
grey seal
The grey seal (''Halichoerus grypus'') is found on both shores of the North Atlantic Ocean. In Latin Halichoerus grypus means "hook-nosed sea pig". It is a large seal of the family Phocidae, which are commonly referred to as "true seals" or " ...
s (''Halichoerus grypus'') along the northern European coast.
In 2002, an epizootic of PDV along the
North Sea
The North Sea lies between Great Britain, Norway, Denmark, Germany, the Netherlands and Belgium. An epeiric sea, epeiric sea on the European continental shelf, it connects to the Atlantic Ocean through the English Channel in the south and the ...
coast resulted in the deaths of 21,700 seals, estimated to be 51% of the population.
Antibodies to PDV have been found in a number of carnivorous mammal species in the Western North Atlantic, including
polar bears, and the
Atlantic walrus.
The suddenness of the emergence of PDV and related viruses in aquatic mammals has implicated environmental changes as the cause. Pollutants have been posited as contributors by interfering with the ability of animals to mount a defense against infection. Alternatively,
climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to ...
and
overfishing may have forced aquatic species that naturally harbour the viruses into new areas, exposing immunologically susceptible populations.
References
{{Taxonbar, from=Q29004632, from2=Q5040284
Morbilliviruses
Pinniped diseases
Animal viral diseases