Abstract Title
Non-invasive (environmental) sampling of wild ducks for active Avian Influenza surveillance
Abstract
Low Pathogenic Avian Influenza (LPAI) typically results in mild symptoms in birds; yet subtypes H5/H7 have the potential to mutate into Highly Pathogenic Avian Influenza (HPAI). HPAI subtype H5 is circulating globally, causing outbreaks in wild birds, poultry, dairy cattle (United States only) and mass mortality in marine carnivores. Concerns have been raised about its pandemic potential.
From 2006 to 2023, HPAI studies in Germany showed passive, rather than active surveillance as more effective in detecting cases. However, active surveillance leans towards LPAI detection, and due to its time- and resource-intensive demands, a simplified, non-invasive approach is needed.
Mallards (Anas platyrhynchos), present year-round at the Baltic shallows of the Greifswalder Bodden, Germany, are attracted to wheat covered with 5L of water in small bins. Ducks feeding on the wheat have close oropharyngeal contact with the water and may release viral particles into it if infected. Virocult® swabs are then taken from the water three times weekly and analyzed using pan Influenza A-real-time RT-qPCR.
Between June 2022 and December 2023, 243 samples were analyzed, with 12 (5%) testing positive, including subtypes H3N8, H11N9, and highly pathogenic H5. However, the viral load in these positive samples was too low to allow for sequencing, isolation, or further characterization.
While this approach is promising, virus enrichment techniques are sought to improve sensitivity. Comparison of different virus concentration methods are currently under investigation, aiming to increase detection rates qualitatively as well us recovery of virus loads quantitatively. The results of these improvements will be presented.
From 2006 to 2023, HPAI studies in Germany showed passive, rather than active surveillance as more effective in detecting cases. However, active surveillance leans towards LPAI detection, and due to its time- and resource-intensive demands, a simplified, non-invasive approach is needed.
Mallards (Anas platyrhynchos), present year-round at the Baltic shallows of the Greifswalder Bodden, Germany, are attracted to wheat covered with 5L of water in small bins. Ducks feeding on the wheat have close oropharyngeal contact with the water and may release viral particles into it if infected. Virocult® swabs are then taken from the water three times weekly and analyzed using pan Influenza A-real-time RT-qPCR.
Between June 2022 and December 2023, 243 samples were analyzed, with 12 (5%) testing positive, including subtypes H3N8, H11N9, and highly pathogenic H5. However, the viral load in these positive samples was too low to allow for sequencing, isolation, or further characterization.
While this approach is promising, virus enrichment techniques are sought to improve sensitivity. Comparison of different virus concentration methods are currently under investigation, aiming to increase detection rates qualitatively as well us recovery of virus loads quantitatively. The results of these improvements will be presented.
Co-Author(s)
Joaquín Neumann-Heise (a), Francesca Isabel Rondi (b), Timm Harder (c), Christoph Staubach (d), Sascha Knauf (a,e), Anja Globig (a)
(a) Institute of International Animal Health/One Health, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
(b) Scienze Biotecnologiche Veterinarie, Università degli Studi di Milano, Milano, Italy
(c) Institute of Diagnostic Virology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
(d) Institute of Epidemiology, Friedrich-Loeffler-Institut, Greifswald-Insel Riems, Germany
(e) Professorship for One Health/International Animal Health, Faculty of Veterinary Medicine, Justus Liebig University, Giessen, Germany
Abstract Category
Notable outbreaks, field and molecular epidemiology, and surveillance in wild birds