Acknowledgements
This work was partially funded by CEVA Santé Animale (swIAV analysis). Silvana Sosa Portugal was supported by an FIP fellowship of Universitat Autònoma de Barcelona thanks to fundingof CEVA Santé Animale. Our grateful thanks to Gwenaelle Dauphin, Kathrin Lillie-Jaschinski and Stefan Pesch for the critical reading of the manuscript.