Bluetongue disease is transmitted by bites from small mosquitoes. Infection with the subtype 3 bluetongue virus (serotype 3, also called BTV-3) causes severe symptoms, such as fever, inflammation of the mucous membranes, swelling and lameness, particularly in sheep. The mortality rate can be very high. The disease often causes only mild symptoms in cattle; however, severe symptoms and a reduction in milk production can sometimes be observed. Bluetongue disease is one of the epizootic diseases that must be combated and is therefore subject to mandatory reporting. If animal keepers notice suspicious symptoms, they must immediately inform a veterinarian. The pathogen responsible for bluetongue disease does not pose a danger to humans. Meat and dairy products can be consumed without fear.
Bluetongue virus serotype 3 infection was discovered on 29 August 2024 in two sheep in the canton of Jura and one sheep in the canton of Solothurn. Since 2023, BTV-3 has been spreading rapidly in Europe. It has now reached Switzerland from the north. Animal movements remain possible without restrictions within the country. The first case of bluetongue disease in the country was detected in 2007, but it was due to serotype 8 (BTV-8). Between 2008 and 2010, Switzerland carried out a large-scale vaccination programme.
There are currently three vaccines against BTV-3, but none of them are authorised in Switzerland or the EU. The latter has a legal basis that allows its member states, under certain conditions, to approve the use of an unauthorised vaccine. This is not the case in Switzerland, where vaccine manufacturers can, however, submit an application for authorisation to Swissmedic, which will process it as a priority and in an accelerated procedure. Vaccines can reduce symptoms, but they cannot prevent infection or the spread of the virus.
Measures for the protection of livestock
It is hardly possible to completely protect animals from mosquitoes. However, the use of mosquito nets and physical barriers helps to reduce the risk of bites and the spread of the virus. The application of insecticides and repellents can also help to reduce the number of mosquitoes in the barn and around the animals. In addition, it is recommended to keep animals away from stagnant water, which is an ideal breeding ground for mosquitoes.
Address for sending questions
Federal Food Safety and Veterinary Office (FSVO)
Media Service
Tel. 058 463 78 98
media@blv.admin.ch
