The first cases of Bluetongue this summer have been detected on imported rams in Lewes, East Sussex and Hemel Hempstead, Hertfordshire.
The animals originated from the same premises within the BTV8 Restricted Zone in Central France.
They were discovered after post-import testing carried out by Defra on all Bluetongue susceptible animals arriving from Europe.
The animals were also checked in France.
All protection zones in Europe run along the same lines and it is legally possible to move susceptible animals from the BTV8 Protection Zone in France to the English and Wales protection zone and vice versa.
Defra said it was “therefore not unexpected to find infected animals in the protection zone”.
Bluetongue was recently confirmed in the Netherlands and large areas of France, despite widespread vaccination programmes.
Full investigations are underway on the UK outbreak and there is no evidence to suggest that the virus is circulating between local midge and animals populations in the local areas.
The Bluetongue mass vaccination programme, which began in April this year, led to about 21.5m doses begin available to farmers to protect their stock.
Deputy Chief veterinary officer, Alick Simmons, said: “These cases emphasise the need for farmers to be aware of the risks of importing animals from within restricted zones.
“This also highlights the importance of vaccination.
“It is the only effective tool to protect susceptible animals. The message remains clear – don’t hesitate, vaccinate.”
Farmers Weekly Livestock editor Jonathan Long said the first two outbreaks of the summer highlighted the need for UK farmers to remain vigilant and ensure they are aware of the disease status of any stock they are considering importing.
“Bringing stock into the UK from bluetongue infected areas of the Continent, particularly at this time of year represents a massive risk to domestic animals and should be undertaken with extreme caution.
“All UK farmers should vaccinate their stock as soon as the protection zone allows to give maximum protection to both their own animals and those of their fellow farmers.”
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