Emerging highly pathogenic H5 avian influenza viruses in France during winter 2015/16: phylogenetic analyses and markers for zoonotic potential

François-Xavier Briand (1, 2) , Audrey Schmitz (1, 2) , Katell Ogor (1, 2) , Aurélie Le Prioux (1, 2) , Cécile Guillou-Cloarec (1, 2) , Carole Guillemoto (1, 2) , Chantal Allée (1, 2) , Marie-Odile Le Bras (1, 2) , Edouard Hirchaud (3, 2) , Hélène Quenault (1, 2) , Fabrice Touzain (3, 2) , Martine Cherbonnel-Pansart (1, 2) , Evelyne Lemaitre (1, 2) , Céline Courtillon (1, 2) , Hélène Gares (4) , Patrick Daniel (5) , Alexandre Fediaevsky (6) , Pascale Massin (1, 2) , Yannick Blanchard (2, 3) , Nicolas Eterradossi (1, 2) , Sylvie van der Werf (7, 3) , Véronique Jestin (3) , Eric Niqueux (1, 2)

1 Laboratoire de Ploufragan-Plouzané-Niort [ANSES]
2 UBL - Université Bretagne Loire
3 ANSES - Agence nationale de sécurité sanitaire de l'alimentation, de l'environnement et du travail
4 LDAR 24 - Laboratoire départemental d'analyse et de recherche de Dordogne
5 Laboratoires des Pyrénées et des Landes
6 DGAL - Direction Générale de l'Alimentation
7 GMV-ARN (UMR_3569 / U-Pasteur_2) - Génétique Moléculaire des Virus à ARN - Molecular Genetics of RNA Viruses

Several new highly pathogenic (HP) H5 avian influenza virus (AIV) have been detected in poultry farms from south-western France since November 2015, among which an HP H5N1. The zoonotic potential and origin of these AIVs immediately became matters of concern. One virus of each subtype H5N1 (150169a), H5N2 (150233) and H5N9 (150236) was characterised. All proved highly pathogenic for poultry as demonstrated molecularly by the presence of a polybasic cleavage site in their HA protein – with a sequence (HQRRKR/GLF) previously unknown among avian H5 HPAI viruses – or experimentally by the in vivo demonstration of an intravenous pathogenicity index of 2.9 for the H5N1 HP isolate. Phylogenetic analyses based on the full genomes obtained by NGS confirmed that the eight viral segments of the three isolates were all part of avian Eurasian phylogenetic lineage but differed from the Gs/Gd/1/96-like lineage. The study of the genetic characteristics at specific amino acid positions relevant for modulating the adaptation to and the virulence for mammals showed that presently, these viruses possess most molecular features characteristic of AIV and lack some major characteristics required for efficient respiratory transmission to or between humans. The three isolates are therefore predicted to have no significant pandemic potential.

Mots clés: Avian influenza; H5; Zoonotic Potential; highly pathogenic; phylogeny

Domaines: Sciences du Vivant [q-bio]

François-Xavier Briand, Audrey Schmitz, Katell Ogor, Aurélie Le Prioux, Cécile Guillou-Cloarec, et al.. Emerging highly pathogenic H5 avian influenza viruses in France during winter 2015/16: phylogenetic analyses and markers for zoonotic potential. Eurosurveillance, 2017, 22 (9), ⟨10.2807/1560-7917.ES.2017.22.9.30473⟩. ⟨pasteur-04097764⟩