Efficacy of an adenovirus-vectored foot-and-mouth disease virus serotype A subunit vaccine in cattle using a direct contact transmission model

Table 3 Efficacy Study 2. Summary of protection based on clinical and laboratory results

Treatment Group		Percent Protection from Outcomes					Percent Positive for Antibodies to FMDV NSPs
Treatment Group	N	Clinical FMD (1–15 dpcc)	FMDV or FMDV RNA in plasma (0–7, 9 dpcc)	FMDV RNA in oronasal fluid (0, 2, 4 dpcc)	FMDV RNA in probang (27, 34, 41 dpcc)	FMDV in probang (27, 34, 41 dpcc)	Percent Positive for Antibodies to FMDV NSPs
T1: IDL challenged seeder steers	10	0%	ND	ND	ND	ND	ND
T2: 1^o AdtA24 5 × 10¹⁰ PU vaccinated; Intermingled with 10 IDL challenged ‘seeder steers’ for 2–3 days	12	100% No oronasal lesions	100%	0%	18%	27%	9%^a - 0 dpcc 91% -30 dpcc
T3: 1^o naïve; Intermingled with 10 IDL challenged ‘seeder steers’ for 2–3 days	6	0%	0%	0%	17%	17%	0% - 0 dpcc 100%-30 dpcc
T4: 2^o AdtA24 5 × 10¹⁰ PU vaccinated; Intermingled with 6 T2: 1^o vaccinated and exposed steers (Room 1)	4	100% No oronasal lesions	100%	100%	100%	100%	0% - 0 and 30 dpcc
T5: 2^o naïve; Intermingled with 6 T2: 1^o vaccinated and exposed steers (Room 2)	4	100% No oronasal lesions	100%	75%	50%	100%	0% - 0 and 30 dpcc
T6: 2^o naïve; Intermingled with 6 T3: 1^o naïve and exposed steers (Room 3)	4	0%	0%	0%	25%	25%	0% - 0 dpcc 100%-30 dpcc

Dpcc days post contact challenge, NSP nonstructural protein, 1^o primary, 2^o secondary, IDL intradermolingual challenge, PU particle units
^aone false positive (consistent with reported diagnostic specificity rates for this assay [36, 37])

ISSN: 1746-6148