Fig 2. Detection of H5 AIV in swabs from infected SPF chickens with virus isolation and RRT-PCR.

Oral-pharyngeal swabs and cloacal swabs of 10 SPF chickens were collected at 24 h, 36 h and 48 h. The infection dose of SPF chicken was 0.2mL 10³ EID₅₀ of H5 AIV. At 24 h and 36 h, no H5 AIV was detected in oral-pharyngeal samples in traditional virus isolation method while the number of positive trachea swabs through RRT-PCR detection at 24 h and 36 h were 5 and 2 respectively. The number of positive samples in RRT-PCR matched that in virus isolation at 48 h.