Atypical Pathogenicity of Avian Influenza (H3N1) Virus Involved in Outbreak, Belgium, 2019.

Steven Van Borm,Bénédicte Lambrecht,Fabienne Rauw,Philippe Gelaude,Mieke Steensels,Mickaël Cargnel,Thierry Van Den Berg,Virginie Roupie

doi:10.3201/eid2608.191338

Abstract

In 2019, an outbreak of avian influenza (H3N1) virus infection occurred among commercial poultry in Belgium. Full-genome phylogenetic analysis indicated a wild bird origin rather than recent circulation among poultry. Although classified as a nonnotifiable avian influenza virus, it was associated with reproductive tropism and substantial mortality in the field.

Highlights

In 2019, an outbreak of avian influenza (H3N1) virus infection occurred among commercial poultry in Belgium
Of the 2 existing pathotypes, low pathogenicity avian influenza (LPAI) and highly pathogenic avian influenza (HPAI), infection with LPAI virus is mostly undetected in a flock but can cause some respiratory signs, egg drop, lethargy, and limited mortality [2,3]
Avian influenza H5/H7 subtypes are all notifiable to the authorities in Europe because adaptive mutations can influence the polybasic nature of the hemagglutinin (HA) cleavage site, resulting in HPAI emergence [4]

Summary

Introduction

In 2019, an outbreak of avian influenza (H3N1) virus infection occurred among commercial poultry in Belgium. Avian influenza is a highly contagious viral disease of poultry, able to infect all species of birds [1]. The Study In January 2019, H3N1 virus was isolated from an outdoor laying hens farm in Belgium.

Results

Conclusion