Intersegmental recombination between the haemagglutinin and matrix genes was responsible for the emergence of a highly pathogenic H7N3 avian influenza virus in British Columbia.
In February 2004 a highly pathogenic avian influenza (HPAI) outbreak erupted in British Columbia. Investigations indicated that the responsible HPAI H7N3 virus emerged suddenly from a low pathogenic precursor. Analysis of the haemagglutinin (HA) genes of the low and high pathogenic viruses isolated from the index farm revealed the only difference to be a 21 nt insert at the HA cleavage site of the highly pathogenic avian influenza virus. It was deduced that this insert most probably arose as a result of non-homologous recombination between the HA and matrix genes of the same virus. Over the course of the outbreak, a total of 37 isolates with, and 3 isolates without inserts were characterized. The events described here appear very similar to those which occurred in Chile in 2002 where the virulence shift of another H7N3 virus was attributed to non-homologous recombination between the HA and nucleoprotein genes.
Pasick
John
J
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Handel
Katherine
K
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Robinson
John
J
Animal Health Centre, British Columbia Ministry of Agriculture and Food, 1767 Angus Campbell Road, Abbotsford, British Columbia, Canada V3G 2M3.
Copps
John
J
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Ridd
Deidre
D
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Hills
Kevin
K
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Kehler
Helen
H
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Cottam-Birt
Colleen
C
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Neufeld
James
J
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Berhane
Yohannes
Y
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
Czub
Stefanie
S
Canadian Food Inspection Agency, National Centre for Foreign Animal Disease, 1015 Arlington Street, Winnipeg, Manitoba, Canada R3E 3M4.
D000818:Animals; D001717:Birds; D001955:British Columbia; D004196:Disease Outbreaks / Q000662:veterinary*; D006389:Hemagglutinins, Viral / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D009980:Influenza A virus / Q000235:genetics* / Q000472:pathogenicity; D005585:Influenza in Birds / Q000453:epidemiology* / Q000821:virology; D010802:Phylogeny; D011995:Recombination, Genetic; D014763:Viral Matrix Proteins / Q000737:chemistry / Q000235:genetics* / Q000276:immunology; D014774:Virulence
D006389:Hemagglutinins, Viral; D014763:Viral Matrix Proteins