Bluetongue outbreak comes from illegal vaccine
Last week, cattle at three farms in the eastern Netherlands developed bluetongue symptoms despite two of the herds having been vaccinated for BTV8. Tests on them, and on an animal from a fourth farm in the region found by routine tests, revealed a different strain, BTV6.
The Dutch agriculture ministry announced on Tuesday that genetic sequencing at the Institute for Animal Health at Pirbright in Surrey, UK, had shown that the BTV6 matches a vaccine virus strain produced in South Africa. A company there, Onderstepoort Biological Products, makes a widely used live bluetongue vaccine that contains BTV6.