Table 5.: Humoral immune response in ferrets following H7N3 LAIV immunization and challenge virus recovery from respiratory tract after infection with 107 of wild type influenza H7N3 virus.

Vaccine group No.of ferrets HI titers (GMT) after immunization : Challenge on 14 days after second vaccine dose Challenge virus isolation at day 3 pi
Lungs Nasal washes
One dose Two doses No/total Mean virus titer (log10PFU ml-1 ±SD) No/total Mean virus titer
(log10PFU ml-1 ±SD)
H7N3 LAIV 107 EID50 6 23.3 186.7 wt H7N3 107 EID50 0/3 0±0.0 0/3 0±0.0
H7N3 LAIV 107 EID50 6 11.6 173.3 PBS 0/3 0±0.0 0/3 0±0.0
PBS 6 ≤10.0 ≤10.0 wt H7N3 107 EID50 1/3 1.3±0.5 3/3 3.0±0.9
PBS 6 ≤10.0 ≤10.0 PBS 0/3 0±0.0 0/3 0±0.0

2 Groups of six ferrets received two administration of 107 EID50 H7N3 LAIV intranasally in the volume 0.5 ml 28 days apart (Day 0 and Day 28). HAI titers were measured for serum samples collected on day 28 and 42
3 GMTs on day 42 were higher than those on day 21 after immunization (P = 0.027)