Table 5. Serum and nasal HA-specific antibody responses after two doses of the nasal vaccine.

	Isotype	Week	Serum	Nasal wash
GMT (Mean geometric increase)	IgG	0	83.7 (1.00)	80.0 (1.00)
		6	247.7 (2.96)	109.8 (1.37)
	IgA	0	14.6 (1.00)	122.0 (1.00)
		6	36.0 (2.47)	473.5 (3.88)

^a Serum HA-specific antibody titers of < 1:10 were considered negative and arbitrarily assigned a titer of 1:5. ^b Nasal HA-specific antibody responses were determined using concentrated nasal wash samples containing 1 mg/ml total protein. Nasal HA-specific IgG and IgA titers of < 1:160 were considered negative and arbitrarily assigned a titer of 1:80.