Seals killed by mystery virus

The virus that killed almost 200 seals off Sweden's west coast and in Denmark during the summer is not 'seal plague' as was previously thought. Experts are now warning the general public to avoid any contact with seals that are sick or dying.

Tests carried out on the dead seals by British researchers have not revealed any indications that the animals were killed by the seal plague, Dagens Nyheter reports.

“Animals that are sick or dead should be treated as infectious. Since we can’t see that they have contracted any known viruses, we can only conclude that this is a virus which has crossed a species boundary and which could possibly be dangerous to humans,” Tero Härkönen from the Swedish Natural History Museum told the newspaper.

When the sickness broke out during the summer, researchers initially thought that only young seals would be affected as the older ones should have built up an immunity to the seal plague. But as older seals began to die researchers started to notice some other clear differences.

For one thing, the illness did not seem as infectious as before. But when it eventually did strike it lasted longer than the seal plague.

“We do have our suspicions regarding the nature of the virus and are working to confirm these. But until then I wouldn’t like to speculate as to how the infection spread to seals or the level of risk to other species,” said Härkönen.