A new virus, fatal in 70% of cases, is threatening the Dutch rabbit population, the NRC said on Monday.

RHD2 is a recently discovered variant of the RHD virus which causes Rabbit Haemorrhagic Disease in both wild and domestic animals. The new variant has a longer incubation period, making it easier for infection to spread, the NRC said.

Symptoms are hard to spot, but occasionally include a bloody nose, the shakes and high fever, which can cause the rabbit to scream in pain.

Vets at Utrecht University are dealing with unexplained rabbit deaths on a daily basis but say it is impossible to gauge how many have been killed. There is no central registry of pet rabbit deaths and wild ones usually die underground.

However, cases have been recorded across the country, apart from in Zeeland, Flevoland and Friesland. The virus is also in Spain, France, Britain, Germany and possibly Belgium.

The virus is not dangerous to humans and is passed by both direct and indirect contact between rabbits. There are thought to be around 1.2 million tame rabbits in the Netherlands.