The National Veterinary Institute at Lindholm is the national reference laboratory for Bluetongue. Thus, we have the responsibility, within the national surveillance programme, for fast and reliable detection of bluetongue virus (BTV) itself and also for antibodies against this virus in blood and serum/milk samples, respectively. These samples can be received from animals with clinical symptoms, from surveillance programmes or from animals that are to be exported.
In the case of outbreaks it is also our task to identify the serotype of the bluetongue virus responsible for the specific outbreak. There are 24 different serotypes of BTV known. Until recently there had been no cases of this disease in northern Europe but thousands of cases have occurred in the last two years mainly due to serotype 8 but other serotypes (types 1 and 6) have also been recognized recently. Identification of the seroptype is achieved using serotype specific real-time RT-PCRs using either assays developed in house or commercial kits when these are available. It is important to be able to determine the serotype because the vaccination programme currently running in Denmark only includes serotype 8, which does not protect against the other serotypes.
As part of the bluetongue surveillance and research programme we are also, in collaboration with another department at our Institute, participating in a project to characterize the insect vectors responsible for spreading the bluetongue virus in Denmark. The biting midges (Culicoides sp.) are captured, the species determined and finally the presence of BTV determined by real time RT-PCR.
Furthermore, we are currently working on developing a fingerprinting method, using T-RFLP or RFLP, that should enable us to identify and follow the virus involved in individual outbreaks which in the long run could be used to map the origin of the outbreaks.
Contact Anette Bøtner