A large outbreak of bluetongue virus type 8 in Italy

Several outbreaks of bluetongue virus (BTV) type 8 have been identified in goats, cattle and sheep on the Italian island of Sardinia. The first outbreak occurred in October, but was not reported to the World Organization for Animal Health (Woah) until 26 January.

The BTV-8 outbreak has now also reached mainland Italy. On November 14, 3 infected sheep were found in a herd of 273 animals. The infection was definitively diagnosed on January 12 and was also reported to Woah on January 26.

Many animals in Sardinia have been affected by BTV-8. According to the report, there are a total of 212 outbreaks. Sheep are the most affected. 8,324 infected sheep were found in herds totaling more than 90,000 cattle.

High mortality rate among sheep

Of the infected sheep, 3,453 died. This is a high number compared to previous BTV-8 outbreaks. During a previous outbreak of bluetongue virus in the Netherlands, there were no deaths among sheep.

Out of a total of 1,220 infected goats in various herds, 32 became infected and 13 died. In livestock, 16 animals were infected out of 614 animals in the infected herds. No cows died from the virus.

The bluetongue virus found in Sardinia and mainland Italy is very similar to the type found in outbreaks in Corsica and southern France. This is equivalent to 99.9 percent, according to the Italian authorities. It is different from the type responsible for previous bluetongue outbreaks in Europe.