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.

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.

A 4-yr-old big-eyed tree frog (Leptopelis vermiculatus) was submitted with two pea-sized (4-mm diameter), firm, and painful masses on the right side of its back. The two abscess-like masses were surgically opened, and a whitish-yellow pasty content was removed. A Brucella inopinata-like bacterium was obtained in pure culture and was resistant against ampicillin and tylosin but sensitive to the 8 other antibiotics tested. The organism was identified by polymerase chain reaction and sequencing of the 16S ribosomal ribonucleic acid (acc. no. HE608873) and recA (acc. no. HE608874) genes after preliminary misidentification as Ochrobactrum anthropi when using a commercial identification system. To the authors' knowledge, a B. inopinata-like bacterium has not been reported previously in amphibians. The organism is a potential human pathogen and may present a risk for people handling amphibians.

West Nile virus (WNV) and Usutu virus (USUV) are important flaviviruses circulating in Germany. While USUV was first reported more than 10 years ago, WNV has only reached the country in 2018. Wild birds are important amplifying hosts for both viruses. Therefore, we have been monitoring the bird population in different regions of Germany by a previously established network for many years. This report summarizes the results of molecular and/or serological methods of 2345 blood samples from birds of 22 different orders and over 2900 bird carcasses from 2019 and 2020. USUV RNA circulation was found in different regions of Germany, with emphasis on USUV lineages Europe 3 and Africa 3. Increased evidence of USUV lineage Europe 2 was detected in eastern Germany. WNV RNA was found only in birds from the eastern part of the country. The seroprevalence for USUV was between 3.11% and 7.20% in all three regions investigated, whereas the WNV seroprevalence spanned from 14.77% to 16.15% in eastern Germany, with a noticeable tendency for a westward and southward expansion in both years. Thus, wild bird monitoring for WNV and USUV can serve as an early warning system for a human exposure risk.

Avian trichomonosis is a widespread disease in columbids and other birds, caused by ingestion of the unicellular flagellate Trichomonas gallinae which proliferate primarily in the upper respiratory tracts. Studies using genetic analyses have determined some highly pathogenic lineages in birds, but the prevalence and distribution of potentially pathogenic and non-pathogenic T. gallinae lineages in wild birds is still not well known. We examined 440 oral swab samples of 35 bird species collected between 2015 and 2017 in Hesse, central Germany, for Trichomonas spp. infection and for determining the genetic lineages. Of these birds, 152 individuals were caught in the wild and 288 individuals were admitted from the wild to a veterinary clinic. The overall Trichomonas spp. prevalence was 35.6%. We observed significant differences between bird orders, with the highest prevalence in owls (58%) and columbids (50%), while other orders had slightly lower prevalences, with 36% in Accipitriformes, 28% in Falconiformes and 28% in Passeriformes. Among 71 successfully sequenced samples, we found 13 different haplotypes, including two previously described common lineages A/B (20 samples) and C/V/N (36 samples). The lineage A/B has been described as pathogenic, causing lesions and mortality in columbids, raptors and finches. This lineage was found in 11 of the 35 species, including columbids (feral pigeon, woodpigeon, stock dove), passerines (greenfinch, chaffinch, blackbird) and raptors (common kestrel, sparrowhawk, red kite, peregrine falcon and common buzzard). One new lineage (R) was found in a sample of a chaffinch. In conclusion, we found that the prevalence of Trichomonas spp. infection in wild birds was high overall, and the potentially pathogenic lineage A/B was widespread. Our findings are worrying, as epidemic outbreaks of trichomonosis have already been observed in Germany in several years and can have severe negative effects on bird populations. This disease may add to the multiple pressures that birds face in areas under high land-use intensity.

SUMMARY Antemortem diagnosis of avian aspergillosis is very challenging. Diagnostic assays using blood samples would aid in an early and more definitive diagnosis. In the current study, detection of anti-Aspergillus antibodies, Aspergillus antigen, and Aspergillus toxin (fumigaclavine A), protein electrophoresis and measurement of acute-phase protein concentrations were performed on serum of 18 adult and plasma of 21 juvenile gyr–saker hybrid falcons (Falco rusticolus × Falco cherrug). Adult (n = 15) and juvenile (n = 18) falcons were experimentally inoculated with different dosages of the same strain of Aspergillus fumigatus and an additional three falcons from each age group were used as uninfected control animals. Blood samples were collected prior to inoculation and at 28 days postinoculation. Of the 33 inoculated falcons, 16 demonstrated clinical signs (vomiting, greenish urates, dyspnea, ruffled feathers) commonly associated with aspergillosis and in 14 falcons necropsy revealed aspergillosis gr... RESUMEN Comparación de las herramientas de diagnóstico para la detección de la aspergilosis en muestras de sangre de halcones infectados experimentalmente. El diagnóstico antemortem de la aspergilosis aviar es muy difícil. Los ensayos de diagnóstico utilizando muestras de sangre podrían ayudar en el diagnóstico precoz y definitivo. En el estudio actual, se llevó a cabo la detección de anticuerpos anti-Aspergillus, la detección del antígeno de Aspergillus, y de la toxina de Aspergillus (fumigaclavina A), el análisis de proteínas por electroforesis y la medición de las concentraciones de proteínas de la fase aguda en suero de 18 halcones adultos y en 21 muestras de plasma de halcones juveniles híbridos gyr-saker (Falco rusticolus × Falco cherrug). Halcones adultos (n = 15) y juveniles (n = 18) fueron inoculados experimentalmente con diferentes dosis de la misma cepa de Aspergillus fumigatus y otros tres halcones adicionales de cada grupo de edad fueron utilizados como animales control no infectados. Se ...