The only other known case of rabies in a sea mammal was in a ringed seal in Norway's Svalbard islands in the early 1980s. That seal had likely been infected by a rabid arctic fox, researchers said, and there was no evidence of rabies spreading among seals there.

Scientist in South Africa believe they have successfully identified the first time the rabies virus has spread to sea mammals, in this case among 24 dead Cape fur seals. The bodies of the sea mammals were discovered in various locations across the west and south coast of the country, according to state veterinarian Dr. Lesley van Helden.