Highly Pathogenic Avian Influenza A(H5N8) Virus Spread by Short- and Long-Range Transmission, France, 2016-17.

François-Xavier Briand ,Béatrice Grasland,Florian Kerbrat,Yannick Blanchard,Axelle Scoizec,Claire Martenot,Carole Guillemoto,Aurélie Le Prioux,Edouard Hirchaud,Katell Ogor,Nicolas Eterradossi,Chantal Allée,Sophie Le Bouquin,Marina Chatel,Audrey Schmitz,Martine Cherbonnel,Pascale Massin,Éric Niqueux ,Véronique Béven ,Cécile Guillou-Cloarec

doi:10.3201/eid2702.202920

Abstract

We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. Genotype A viruses caused dramatic economic losses in the domestic duck farm industry in southwestern France. Our phylogenetic analysis suggests that genotype A viruses formed 5 distinct geographic clusters in southwestern France. In some clusters, local secondary transmission might have been started by a single introduction. The intensity of the viral spread seems to correspond to the density of duck holdings in each production area. To avoid the introduction of disease into an unaffected area, it is crucial that authorities limit the movements of potentially infected birds.

Highlights

We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17
France had 539 cases of highly pathogenic avian influenza (HPAI) A(H5N8) infections, 51 in wild birds and 488 in poultry flocks, most of which occurred at duck farms producing foie gras [18]
The 488 domestic cases were mainly in southwestern France, whereas H5N8 infection was more common in wild birds in other areas of France (Appendix Table 1)

Summary

Introduction

We detected 3 genotypes of highly pathogenic avian influenza A(H5N8) virus in France during winter 2016–17. H5 and H7 subtypes can become highly pathogenic avian influenza (HPAI) viruses after the evolution of multiple basic amino acids in the cleavage site of hemagglutinin protein [2,3]. This mutation enables the virus to replicate efficiently in all organs, causing a severe and often fatal systemic disease. Since 1996, highly pathogenic H5 viruses of the A/goose/Guangdong/1/96 (Gs/GD/96) lineage have caused recurrent outbreaks with high death rates in birds These HPAIs are categorized into 10 distinct clades (0–9) on the basis of hemagglutinin sequences [7]. The second period spanned February 3–March 23, 2017 and comprised a single spatiotemporal cluster [20]

Methods

Results

Conclusion