Schmallenberg virus continues to spread

Schmallenberg virus continues to spread: nearly 300 farms in Germany affected

06.02.2012

The spread of the until recently unknown Schmallenberg virus in the herds of cattle and sheep nationwide has increased significantly in recent months. Meanwhile almost 300 businesses are affected. The lambs or calves of the infected animals often come with severe malformations and not viable to the world.

For example, the number of reported severe malformations and stillbirths in sheep and cattle has increased significantly over the past six months as the mysterious epidemic spread. Initially, mainly animals in North Rhine-Westphalia and Lower Saxony were affected. In the meantime, the Schmallenberg virus has also appeared more frequently in other federal states and has for the first time been detected in Hamburg. The Friedrich-Loeffler-Institut (FLI) has investigated numerous samples as a federal research institute for animal health and has so far proven the novel virus in more than 280 companies.

Malformations and stillbirths by the Schmallenberg virus
According to the FLI on the Baltic island of Riems, the occurrence of the enigmatic new animal disease was first detected in cattle in Germany in November last year. The experts of the Friedrich-Loeffler-Institut identified a virus that was attributed to the genus Orthobunyaviruses and named after its first location as a virus „Schmallenberg virus“ was designated. Orthobunyaviruses are relatively widespread in cattle on other continents, such as Australia or Africa, and the disease itself is usually relatively mild. However, in the case of infection of pregnant animals, considerable health problems for their offspring threaten. For example, embryonic developmental disorders, premature birth and impaired fertility in the offspring may occur. In Germany, infections with such viruses were until recently largely unknown, but since the summer of 2011, initially in North Rhine-Westphalia and then in Lower Saxony, more cattle with corresponding symptoms were observed.

Current infections only the tip of the iceberg?
In the beginning, the responsible veterinarians and authorities thought of the spread of bluetongue in the face of symptoms such as fever (over 40 degrees Celsius), reduced general well-being, loss of appetite and a decrease in milk production by up to 50 percent. Most of the symptoms disappeared after a few days, so that initially no further health problems were to be expected. In the following months, however, the number of severe malformations and stillbirths in sheep and cattle increased significantly, which is due to the long-term effect of Schmallenberg virus. According to the researchers, the viruses are transmitted by mosquitoes and biting midges (bearded mosquitoes). The dams that are currently giving birth to the lambs and calves, probably already in the summer and fall of 2011, were infected, said FLI spokeswoman Elke Reinking. Thus, the current evidence of the virus in sheep and cattle herds may only be the tip of the iceberg.

Looking for a vaccine against the Schmallenberg virus
After the spread of the Schmallenberg virus has increased rapidly in recent months, the introduction of a reporting obligation for the infectious disease is currently being prepared at federal level. This is in the opinion of the chief veterinarian in the Federal Ministry of Agriculture, Karin Schwabenbauer, „necessary for the veterinary authorities to have a comprehensive overview of the disease and to take control measures.“ Also the Friedrich Loeffler Institute works according to own representation at present with high pressure at the development of a vaccine against the Schmallenberg virus. However, according to the assessment of the Hamburg Minister of Agriculture Till Backhaus (SPD) is not expected for the time being. „Therefore, I do not want to raise too much hopes for a quick solution in 2012 ", Backhaus explained in his statement on the current evidence of the Schmallenberg virus in Hamburg.

The spread of the novel virus is not only concentrated in Germany but has also reached England, Belgium, the Netherlands and France. Concerned about importing the virus, Russia and Mexico have already imposed a ban on the importation of pregnant sheep and cattle, as well as bovine semen and embryos from Germany. According to the experts, there is no risk of infection by the novel pathogens, but so far there is no final assessment of the possible health risks of the Schmallenberg virus. (Fp)

Also read:
Schmallenberg virus: More and more lambs affected
Unknown virus discovered in cattle

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