A virus common in dogs has killed more than 11,000 seals in Western Europe's coastal waters this summer and humans can do little to stop the spread of the disease, a Dutch biologist says.

Up to 80 percent of the seals in the North Sea and Kattegat waters between Denmark and Sweden might die, Ab Osterhaus said."Canine distemper virus, or a closely related virus, is the primary cause of the seal deaths," said Osterhaus.