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Wild birds play an important role as reservoir hosts and vectors for zoonotic arboviruses and foster their spread. Usutu virus (USUV) has been circulating endemically in Germany since 2011, while West Nile virus (WNV) was first diagnosed in several bird species and horses in 2018. In 2017 and 2018, we screened 1709 live wild and zoo birds with real-time polymerase chain reaction and serological assays. Moreover, organ samples from bird carcasses submitted in 2017 were investigated. Overall, 57 blood samples of the live birds (2017 and 2018), and 100 organ samples of dead birds (2017) were positive for USUV-RNA, while no WNV-RNA-positive sample was found. Phylogenetic analysis revealed the first detection of USUV lineage Europe 2 in Germany and the spread of USUV lineages Europe 3 and Africa 3 towards Northern Germany. USUV antibody prevalence rates were high in Eastern Germany in both years. On the contrary, in Northern Germany, high seroprevalence rates were first detected in 2018, with the first emergence of USUV in this region. Interestingly, high WNV-specific neutralizing antibody titers were observed in resident and short-distance migratory birds in Eastern Germany in 2018, indicating the first signs of a local WNV circulation.

One year after the first autochthonous transmission of West Nile virus (WNV) to birds and horses in Germany, an epizootic emergence of WNV was again observed in 2019. The number of infected birds and horses was considerably higher compared to 2018 (12 birds, two horses), resulting in the observation of the first WNV epidemy in Germany: 76 cases in birds, 36 in horses and five confirmed mosquito-borne, autochthonous human cases. We demonstrated that Germany experienced several WNV introduction events and that strains of a distinct group (Eastern German

By systematically setting up a unique nation-wide wild bird surveillance network, we monitored migratory and resident birds for zoonotic arthropod-borne virus infections, such as the flaviviruses West Nile virus (WNV) and Usutu virus (USUV). More than 1900 wild bird blood samples, from 20 orders and 136 different bird species, were collected between 2014 and 2016. Samples were investigated by WNV and USUV-specific real-time polymerase chain reactions as well as by differentiating virus neutralization tests. Dead bird surveillance data, obtained from organ investigations in 2016, were also included. WNV-specific RNA was not detected, whereas four wild bird blood samples tested positive for USUV-specific RNA. Additionally, 73 USUV-positive birds were detected in the 2016 dead bird surveillance. WNV neutralizing antibodies were predominantly found in long-distance, partial and short-distance migrants, while USUV neutralizing antibodies were mainly detected in resident wild bird species, preferentially with low seroprevalences. To date, WNV-specific RNA has neither been detected in wild birds, nor in mosquitoes, thus, we conclude that WNV is not yet present in Germany. Continued wild bird and mosquito monitoring studies are essential to detect the incursion of zoonotic viruses and to allow risk assessments for zoonotic pathogens.

The emergence of West Nile virus (WNV) and Usutu virus (USUV) in Europe resulted in significant outbreaks leading to avifauna mortality and human infections. Both viruses have overlapping geographical, host and vector ranges, and are often co‐circulating in Europe. In Germany, a nationwide bird surveillance network was established to monitor these zoonotic arthropod‐borne viruses in migratory and resident birds. In this framework, co‐infections with WNV and USUV were detected in six dead birds collected in 2018 and 2019. Genomic sequencing and phylogenetic analyses classified the detected WNV strains as lineage 2 and the USUV strains as lineages Africa 2 (n = 2), Africa 3 (n = 3) and Europe 2 (n = 1). Preliminary attempts to co‐propagate both viruses in vitro failed. However, we successfully cultivated WNV from two animals. Further evidence for WNV‐USUV co‐infection was obtained by sampling live birds in four zoological gardens with confirmed WNV cases. Three snowy owls had high neutralizing antibody titres against both WNV and USUV, of which two were also positive for USUV‐RNA. In conclusion, further reports of co‐infections in animals as well as in humans are expected in the future, particularly in areas where both viruses are present in the vector population.

It has often been shown that the amount of media use is negatively related to cognitive outcomes. The more time spent on media the poorer cognitive performance is. This association has mainly been found for general-audience, violent, and action-loaded contents but not for educational contents. Typically, long-term-explanations like the time-displacement hypothesis are considered to account for this relation, although this cannot fully explain the association. Additionally short-term explanations should be considered, since it can be expected that media-induced stress can impair information processing. The present study compares short-term effects regarding memory performance and the ability to concentrate, using four different experimental conditions (high- vs. low-arousing films and video games). It was also examined if the experienced level of stress mediates group differences and if habitual media, habitual use of age-restricted contents or the trait sensation seeking moderate this mediation. Participants consisted of N = 117 university students. They were asked to learn written items before media use and to recall these after having used the media. Further, the ability to concentrate was measured. Experimental groups differed with regard to the cognitive outcome measures after media use. A significant univariate difference was found for high- vs. low-arousing contents in general (independent of type of media), the high-arousing content leading to poorer ability to concentrate after media use. The expected mediating and moderating effects are not supported. The study yields evidence that short-term mechanisms might play a role in explaining the negative correlations between media use and cognitive performance.

West Nile virus (WNV) is a mosquito-borne virus that originates from Africa and at present causes neurological disease in birds, horses, and humans all around the globe. As West Nile fever is an important zoonosis, the role of free-ranging domestic poultry as a source of infection for humans should be evaluated. This study examined the pathogenicity of an Italian WNV lineage 1 strain for domestic poultry (chickens, ducks, and geese) held in Germany. All three species were subcutaneously injected with WNV, and the most susceptible species was also inoculated via mosquito bite. All species developed various degrees of viremia, viral shedding (oropharyngeal and cloacal), virus accumulation, and pathomorphological lesions. Geese were most susceptible, displaying the highest viremia levels. The tested waterfowl, geese, and especially ducks proved to be ideal sentinel species for WNV due to their high antibody levels and relatively low blood viral loads. None of the three poultry species can function as a reservoir/amplifying host for WNV, as their viremia levels most likely do not suffice to infect feeding mosquitoes. Due to the recent appearance of WNV in Germany, future pathogenicity studies should also include local virus strains.

Tick-borne encephalitis virus (TBEV) is a tick-borne Flavivirus, which is endemic in many European countries and throughout most of Asia (Mansfield et al., 2009). Originally, three different TBEV subtypes were distinguished: The Western European, the Siberian and the Far Eastern subtype (Valarcher et al., 2015). Just recently, two additional subtypes have been proposed (Dai, Shang, Lu, Yang, & Xu, 2018;Kovalev & Mukhacheva, 2017). TBEV is circulating in small, geographically defined natural foci between the tick, as vector and small mammals such as rodents, as hosts and reservoirs (Dobler, Gniel, Petermann,