Since many variables can affect the host's virus shedding and the course of disease [31, 32] , prior to evaluation of vaccine constructs, the pathogenicity after challenge with the LPAI subtype H5N2 virus was evaluated. A biphasic virus shedding was observed in this study. For the LPAI subtype H5N2, the peaks for tracheal and cloacal shedding were at days 4 and 8 postinfection.