Press release from ProMED mail
 Human sera, PCR, Germany - no evidence of human infection
Date: Mon 2 Apr 2012
Source: Press release of the Robert Koch Institute [in German, trans. Sabine Zentis, edited]
To determine whether Schmallenberg virus [SBV] not only infects ruminants but also humans, the Robert Koch Institute has developed laboratory tests and conducted a study with sheep farmers. "The results of the study show that this new virus hasn't led to infection in people in contact with large amounts of the virus," Reinhard Burger, president of the Robert Koch Institute, says. The Robert Koch Institute is the national public health institute in Germany. "With regard to the identification of new health risks, the RKI plays a central role in the sense of an early warning system," Burger emphasized.
Scientists of the Friedrich-Loeffler-Institute / Federal Research Institute for Animal Health [FLI] have detected SBV in cattle, sheep and goats since November 2011 and provisionally named the virus after the place of origin of the 1st sample (the village of Schmallenberg). SBV (which belongs to the group of Orthobunyaviruses) is transmitted by certain mosquitoes [midges]. Since then, the number of farms affected has, according to FLI, risen to about 1000; more than 800 of them are sheep farms. The infection of the animals at a particular stage of pregnancy can cause serious defects of the foetus.
So far, there has been no indication that infections or disease in humans from contact with SBV could occur. The closely related viruses of SBV (3 representatives of the Simbu serogroup) don't infect humans. But SBV has new genetic and animal-related clinical and epidemiological characteristics. More distantly related viruses of SBV (including 2 representatives of the Simbu serogroup) can also cause disease in humans.
The RKI has, therefore, as a precautionary measure, conducted a survey of sheep farmers, as they have the most intensive contact with the new virus. On 29 Feb 2012, scientists from the RKI attended a meeting of 60 cattle and sheep farmers in North Rhine-Westphalia and took blood samples for laboratory testing [see item 4 in archived post 20120306.1062871].
A questionnaire revealed no information that would have raised the suspicion that contact with infected animals could result in disease symptoms. The scientists of the RKI detected no antibodies against SBV in the blood samples collected. Antibodies would have shown an infection with the virus. In examined blood samples of some animal owners with non-specific symptoms such as fever or headache, a so-called PCR test that can detect the virus gave negative results.
A relatively high number of humans with intensive contact with the pathogen has been investigated in this study. Extremely rare infection events, however, cannot be detected by such a study. Based on the study results and the genetic characteristics of the new virus, the risk of infection in humans can be assessed as extremely low.
Castleview English Longhorns
D-52385 Nideggen, Germany