Shamonda virus has been found in British livestock for the first time.
Two dairy farms tested positive in October. One is in Powys, Wales. The other is in Shropshire, England.
Samples went to APHA laboratories in Weybridge. The announcement came on November 2.
The virus travels in Culicoides biting midges. One bite can pass it from animal to animal.
14 western European countries have recorded cases this year, including Jersey and Ireland.
Sick cows may get fever, diarrhoea, and lethargy. Milk output can drop.
Infection during pregnancy can cause abortions or birth defects, according to European reports.
One case was found in a severely immunosuppressed person in Lyon, France. Officials say the risk to people is very low.
The Food Standards Agency says there is no evidence of a food safety risk.
There is no vaccine and no specific treatment. Vets can only give supportive care.
Midge activity slows in winter. That should slow the spread. The real test comes next spring.
Farmers should check their animals and call a vet at the first sign of illness. Full story on Rive News.
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