Abstract

Usutu virus (USUV) is a zoonotic arbovirus causing avian mass mortalities. The first outbreak in North-Western Germany occurred in 2018. This retrospective analysis focused on combining virological and pathological findings in birds and immunohistochemistry. 25 common blackbirds, one great grey owl, and one kingfisher collected from 2011 to 2018 and positive for USUV by qRT-PCR were investigated. Macroscopically, most USUV infected birds showed splenomegaly and hepatomegaly. Histopathological lesions included necrosis and lymphohistiocytic inflammation within spleen, Bursa fabricii, liver, heart, brain, lung and intestine. Immunohistochemistry revealed USUV antigen positive cells in heart, spleen, pancreas, lung, brain, proventriculus/gizzard, Bursa fabricii, kidney, intestine, skeletal muscle, and liver. Analysis of viral genome allocated the virus to Europe 3 or Africa 2 lineage. This study investigated whether immunohistochemical detection of double-stranded ribonucleic acid (dsRNA) serves as an alternative tool to detect viral intermediates. Tissue samples of six animals with confirmed USUV infection by qRT-PCR but lacking viral antigen in liver and spleen, were further examined immunohistochemically. Two animals exhibited a positive signal for dsRNA. This could indicate either an early state of infection without sufficient formation of virus translation products, occurrence of another concurrent virus infection or endogenous dsRNA not related to infectious pathogens and should be investigated in more detail in future studies.

Details

Title
Analysis of avian Usutu virus infections in Germany from 2011 to 2018 with focus on dsRNA detection to demonstrate viral infections
Author
Störk Theresa 1 ; de le Roi Madeleine 1 ; Haverkamp Ann-Kathrin 1 ; Jesse, Sonja T 2 ; Peters, Martin 3 ; Fast, Christine 4 ; Gregor, Katharina M 1 ; Könenkamp, Laura 5 ; Steffen Imke 5 ; Ludlow, Martin 2 ; Beineke, Andreas 1 ; Hansmann Florian 6 ; Wohlsein, Peter 1 ; Osterhaus Albert D M E 2 ; Baumgärtner, Wolfgang 1 

 University of Veterinary Medicine Hanover Foundation, Department of Pathology, Hannover, Germany (GRID:grid.412970.9) (ISNI:0000 0001 0126 6191) 
 University of Veterinary Medicine Hanover, Research Center for Emerging Infections and Zoonoses, Hanover, Germany (GRID:grid.412970.9) (ISNI:0000 0001 0126 6191) 
 Chemisches Und Veterinäruntersuchungsamt Westfalen, Arnsberg, Germany (GRID:grid.412970.9) 
 Friedrich-Loeffler-Institut, Federal Research Institute for Animal Health, Institute of Novel and Emerging Infectious Diseases, Greifswald-Insel Riems, Germany (GRID:grid.417834.d) 
 University of Veterinary Medicine Hanover, Research Center for Emerging Infections and Zoonoses, Hanover, Germany (GRID:grid.412970.9) (ISNI:0000 0001 0126 6191); University of Veterinary Medicine Hanover, Institute for Biochemistry, Hanover, Germany (GRID:grid.412970.9) (ISNI:0000 0001 0126 6191) 
 University of Veterinary Medicine Hanover Foundation, Department of Pathology, Hannover, Germany (GRID:grid.412970.9) (ISNI:0000 0001 0126 6191); Leipzig University, Institute of Veterinary-Pathology, Leipzig, Germany (GRID:grid.9647.c) (ISNI:0000 0004 7669 9786) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2611009672
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.