Schmallenberg virus

The Friedrich-Loeffler-Institut informs (as of 17 February 2012)

ab. The lambing season of sheep and of goats has begun. The breeders expect it with great concern, especially in the north-west of Germany. In cows and cattle some cases of animals infected with the Schmallenberg virus occurred. The transmission took place through biting midges – the same small mosquito that transmitted the bluetongue disease a few years ago. As the midges can be carried by the wind a few hundred kilometers per day, further adjacent areas and countries can be affected. The infection presumably occured in the summer/autumn 2011 and severely damaged the development of young animals at an early stage of pregnancy by damaging the brain structure. Now each birth might have to be accompanied carefully and supervised by a veterinarian. The Friedrich-Loeffler-Institute provides careful information. One dreads to think about what might happen, if a similar virus would be invented with affinity to humans...

One can only hope that all animal lovers in the whole society take an interest in this topic and come back down to earth instead of chasing wolf fantasies. Instead, they could contribute to prevent biotechnological research from inventing killer viruses that threaten animals and humans!

Whether this virus is of natural origin or “man-made”, has to be clarified by further research. In the case of bird flu, for example, the global scientific community investigated painstakingly and led quite an open debate: origin was not nature. Each time they have to begin anew, the battle against the virus and the finding of the cause. As if humanity had nothing else to do!

Besides Germany, the Netherlands, Belgium, Great Britain and France have reported cases of Schmallenberg virus, mainly in sheep.
In sheep the Schmallenberg virus was mainly found in the brains of malformed lambs. The abnormalities are a late result of an infection at an earlier stage of pregnancy in summer/autumn 2011.

In November 2011, the Friedrich-Loeffler-Institute, Federal Research Institute for Animal Health (FLI) detected the occurrence of a virus of the genus Orthobunya virus in cattle in Germany for the first time. Comparative analysis of genetic material suggests that the virus is belonging to the Simbu sero-group (Shamonda, Aino, Akabane virus). The virus could be isolated, cultured and breeded. Due to the origin of the sample, it was preliminarily termed as “Schmallenberg virus”.

The detection method developed at the FLI, was distributed to institutions in Belgium, France, England, the Netherlands, Italy and Switzerland.

Moreover, it is still unclear, whether this is a new occurence of this exotic virus or whether Orthobunya viruses have occured in ruminants for quite some time in Europe. Therefore, for a further assessment of this virus, additional studies are needed.

Orthobunya viruses of cattle are common in Australia, Asia and Africa, and there they usually cause  mild clinical symptoms at first. However, if pregnant animals are being infected, partly significant congenital damages, premature births and fertility problems may occur with some delay. Akabane-like viruses are mainly transmitted by biting midges (haematophagous mosquitoes).

These viruses – relevant for cattle – do not pose a risk to humans. They are not zoonotic pathogens. Due to the affinity of the Schmallenberg virus to the Shamonda, Aino and Akabane viruses there supposedly is no risk to humans, too (see also risk assessment of the European Centre for Disease Prevention and Control).     •