|Lee, Donghun - Orise Fellow|
Submitted to: American Association of Avian Pathologists
Publication Type: Abstract Only
Publication Acceptance Date: 3/1/2015
Publication Date: 7/11/2015
Citation: Lee, D., Swayne, D.E. 2015. Comparison of molecular classification and experimental pathogenicity for classification of low and high pathogenicity H5 and H7 avian influenza viruses [abstract]. In: Convention Notes of American Veterinary Medical Association Annual Meeting, July 11-14, 2015, Boston, Massachusetts. CDROM.
Technical Abstract: Highly pathogenic avian influenza (HPAI) viruses, which have been restricted to H5 and H7 subtypes, have caused continuous outbreaks in the poultry industry with devastating economic losses and is a severe threat to public health. Genetic features and severity of the disease in poultry determine whether the infection is classified as low pathogenic avian influenza or HPAI. In particular, avian influenza viruses are classified as highly pathogenic for poultry if: (1) intravenous pathogenicity index in six-week-old chickens is greater than 1.2 or causes at least 75% mortality in four-to eight-week-old chickens infected intravenously; or (2) H5 and H7 viruses contain multiple basic amino acids at the cleavage site of the hemagglutinin (HA) molecule. Here, we compared the HA cleavage site motif and experimental pathogenicity in chickens of previously reported natural H5 and H7 subtype viruses. In most cases, results between the molecular classification and experimental pathogenicity were well-matched, but rare discordant cases between those results have been observed with several viruses. Here, we review and discuss the compatibility of molecular classification and experimental pathogenicity of H5 and H7 subtype viruses.