Bluetongue" By the time the disease is diagnosed (clinically or serologically) the midges capable of transmitting the virus are infected already. As there are currently no means to prevent midges from biting and thus infecting ruminants (not only cattle and sheep but wildlife as well) killing infected animals doesn't make sense.
Finding a clinical case of BT usually is the tip of the iceberg (lots of subclinical cases shown by blood sampling during winter) so talking about infected animals or infected farms doesn't make sense. The region around the holding is "infected" and neither biosecurity nor legislation can prevent the virus from spreading once it is introduced.
As midges can't be eradicated the only sensible option to stop the virus from spreading is the use of a serotype specific, inactivated vaccine.
I don't agree with the term "economic disease". Although the clinical signs and mortality in sheep infected with BTV 8 are not as aggressive as seen with other serotypes of BTV, cattle infected and showing clinical signs are really ill. If treated properly they will survive, but besides the short term lesions of the mouth, tongue or teats they suffer from laminitis for quite a time. The long term effects on calves born to dams infected during pregnany have not been investigated yet nor a suspected reduction of fertility or milk yield after infection. Concerns for animal welfare should prevent the use of the term "economic disease" .
At the moment, the restrictions on movements and exports are clearly putting the most pressure on farmers and breeders but I can fairly well understand that no one in his right mind would buy animals from infected regions. So the calls for a lifting or easing of restrictions are quite stupid as they go without the effort to eradicate the disease.
From my experience (spread of disease in our region despite movement restrictions, housing of animals and extensive use of insecticides) the only way to stop the virus from moving further is to vaccinate in and around the infected areas.
There is no other way to break the cycle of infection (glueing fly swats to cattle tails didn't do the trick :-))
I would strongly recommend that the ones in charge of disease eradication in the countries affected so far get their act together and push for vaccination against BTV 8 the sooner the better. This would not only help the countries affected to get rid of the virus but would prevent the virus from being carried to other countries either by movement of animals or by infected midges.
PS You can put my name and address with my comment, I don't have any problems with this
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