Authors: Wanhong Xu, Yohannes Berhane, Caroline Dubé, Binhua Liang, John Pasick, Gary VanDomselaar & Soren Alexandersen
Brief summary of the paper: The first North American outbreak of highly pathogenic avian influenza (HPAI) involving a virus of Eurasian A/goose/Guangdong/1/1996 (H5N1) lineage began in the Fraser Valley of British Columbia, Canada in late November 2014.
A total of 11 commercial and 1 non-commercial (backyard) operations were infected before the outbreak was terminated. Control measures included movement restrictions that were placed on a total of 404 individual premises, 150 of which were located within a 3 km radius of an infected premise(s) (IP).
A complete epidemiological investigation revealed that the source of this HPAI H5N2 virus for 4 of the commercial IPs and the single non-commercial IP likely involved indirect contact with wild birds. Three IPs were associated with the movement of birds or service providers and localized/environmental spread was suspected as the source of infection for the remaining 4 IPs.
Viral phylogenies, as determined by Bayesian Inference and Maximum Likelihood methods, were used to validate the epidemiologically inferred transmission network. The phylogenetic clustering of concatenated viral genomes and the median-joining phylogenetic network of the viruses supported, for the most part, the transmission network that was inferred by the epidemiologic analysis.