Viruses, Vol. 12, Pages 920: The Emergence of H7N7 Highly Pathogenic Avian Influenza Virus from Low Pathogenicity Avian Influenza Virus Using an in ovo Embryo Culture Model
Viruses, Vol. 12, Pages 920: The Emergence of H7N7 Highly Pathogenic Avian Influenza Virus from Low Pathogenicity Avian Influenza Virus Using an in ovo Embryo Culture Model
Viruses doi: 10.3390/v12090920
Authors:
Amanda H. Seekings
Wendy A. Howard
Alejandro Nuñéz
Marek J. Slomka
Ashley C. Banyard
Daniel Hicks
Richard J. Ellis
Javier Nuñéz-García
Lorian C. Hartgroves
Wendy S. Barclay
Jill Banks
Ian H. Brown
Outbreaks of highly pathogenic avian influenza virus (HPAIV) often result in the infection of millions of poultry, causing up to 100% mortality. HPAIV has been shown to emerge from low pathogenicity avian influenza virus (LPAIV) in field outbreaks. Direct evidence for the emergence of H7N7 HPAIV from a LPAIV precursor with a rare di-basic cleavage site (DBCS) was identified in the UK in 2008. The DBCS contained an additional basic amino acid compared to commonly circulating LPAIVs that harbor a single-basic amino acid at the cleavage site (SBCS). Using reverse genetics, outbreak HPAIVs were rescued with a DBCS (H7N7DB), as seen in the LPAIV precursor or an SBCS representative of common H7 LPAIVs (H7N7SB). Passage of H7N7DB in chicken embryo tissues showed spontaneous evolution to a HPAIV. In contrast, deep sequencing of extracts from embryo tissues in which H7N7SB was serially passaged showed retention of the LPAIV genotype. Thus, in chicken embryos, an H7N7 virus containing a DBCS appears naturally unstable, enabling rapid evolution to HP...
Source: Viruses - Category: Virology Authors: Amanda H. Seekings Wendy A. Howard Alejandro Nu ñéz Marek J. Slomka Ashley C. Banyard Daniel Hicks Richard J. Ellis Javier Nu ñéz-García Lorian C. Hartgroves Wendy S. Barclay Jill Banks Ian H. Brown Tags: Article Source Type: research