New bluetongue virus serotype, BTV-12, identified in the Netherlands

A new variant of the bluetongue virus has been identified in a sheep in Kockengen. It was identified as bluetongue serotype BTV-12, according to research by Wageningen Bioveterinary Research (WBVR, part of Wageningen University & Research). The European Bluetongue Reference Laboratory in Madrid confirmed that the animal in question was infected with BTV-12.

Following the detection of BTV-12 in the sheep in Kockengen, additional research was commissioned by LVVN in eight ruminants in the immediate vicinity (radius of 5 km). One of these animals, a cow, also proved positive for BTV-12 in the analysis of Wageningen Bioveterinary Research. This sample has also been offered to the European Reference Laboratory for confirmation. These results are expected early next week. The cow in question calved in September. The calf was sampled by the NVWA and is currently being examined for the presence of bluetongue.

The Dutch ministry of Agriculture, Fishery, Food Security and Nature (LVVN) and the Dutch Food and Consumer Product Safety Authority (NVWA) have been informed about the new bluetongue variant. Due to the determination of BTV-12, LVVN minister Femke Wiersma has ordered that all bluetongue-positive samples submitted for testing since September 1, to be analyzed again and checked for the presence of BTV-12. The results of this retrospective analysis are expected during the coming week.

Genetically, the two bluetongue variants, BTV-3 and BTV-12, are unrelated. Melle Holwerda, virologist and head of the National Reference Laboratory, therefore cannot yet say anything about the origin of the new variant. “Nor do we know where BTV-12 occurs other than the two positive cases we have identified thus far.” According to Holwerda, the finding of the new variant does highlight the importance of continuing to report suspicions to the NVWA.