TABLE 7.

Immunogenicity and protective efficacy of H5N1 ca vaccine administered by sprayer or by intranasal and intratracheal routes^a

Vaccine/route	AGM no.b	Serum Ab response				Titer of challenge virus in respiratory tissues(log10 TCID50/g)			Titer of challenge virus in swab and lavage fluid (log10 TCID50/ml)
		HAIc		MNd		Nasal turbinates	Trachea	Lung	Nasal swab	Pharyngeal swab	Nasal wash	Tracheal lavage fluid
		Day 42	Day 49	Day 42	Day 49
Mock/sprayer	M1	<20	<20	<20	<20	6.0	7.4	7.0	4.7	3.4	≤0.5	≤0.5
	M2	<20	<20	<20	<20	6.4	6.2	6.0	5.0	4.2	≤0.5	≤0.5
Mock/intranasal + intratracheal	M3	<20	<20	<20	<20	5.4	7.2	7.6	4.2	4.2	≤0.5	≤0.5
	M4	<20	<20	<20	<20	5.7	6.0	6.5	3.2	4.2	≤0.5	≤0.5
H5N1ca/sprayer	S1	40	40	202	202	≤1.5	≤1.5	≤1.5	1.0	1.0	≤0.5	≤0.5
	S2	<20	<20	16	<20	≤1.5	≤1.5	5.0	3.2	1.0	≤0.5	≤0.5
	S3	<20	<20	<20	<20	2.0	6.2	5.6	1.0	3.37	≤0.5	≤0.5
H5N1 ca/intranasal + intratracheal	i.n.+i.t.1	160	160	905	508	≤1.5	≤1.5	1.6	≤0.5	3.2	≤0.5	≤0.5
	i.n.+i.t.2	<20	<20	<20	<20	≤1.5	≤1.5	≤1.5	≤0.5	4.2	≤0.5	≤0.5
	i.n.+i.t.3	160	160	202	254	≤1.5	≤1.5	≤1.5	≤0.5	4.2	≤0.5	≤0.5

^aca, cold adapted.

^bM, mock; S, sprayer; i.n.+i.t., intranasal and intratracheal.

^cThe HAI assay was performed using 0.5 % turkey red blood cells, and titers are expressed as the highest dilution of serum that inhibited agglutination of 8 HAU of virus. The lower limit of detection was 20. Antibody titers from individual animals are listed.

^dNeutralizing Ab titers are expressed as the serum dilution that inhibited infectivity of 100 TCID₅₀ of virus in a microneutralization assay using MDCK cells. The lower limit of detection was 20. Antibody titers from individual animals are listed.