The first rabbit deaths due to the new strain of calicivirus released earlier in autumn have been confirmed by the Otago Regional Council.
In a statement yesterday, council environmental monitoring and operations director Scott MacLean described the news of rabbit deaths as a result of the recently released Korean strain, RHDV1 K5, as "excellent''.
But he said the 100 sites where the K5 variant was released last month needed more time before the virus became widespread.
In 1997 a Czech variant of the rabbit virus RHDV1 was imported and released illegally, but there was "a difference between the natural spread of the virus that's been released now''.
Environment Canterbury biosecurity regional leader Graham Sullivan said the "major nationwide release'' in autumn was expected to overcome the immunity of rabbits to a benign calicivirus strain present in many New Zealand rabbits.
The Otago Regional Council has warned farmers not to interfere with the council's release programme as it could limit the spread of the virus in the long term and allow rabbits to build an immunity to the new strain.
Mr MacLean called for farmers who see dead rabbits on their property to contact a council biosecurity officer so samples could be taken for testing.