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

Table 1 Efficacy Study 1. Summary of outcomes based on clinical and laboratory results

Treatment Group	N	Percent Protected from Lesions (21 dpcc)		Geometric mean FMDV A24/Cruzeiro/BRA/55 VNT titer (log₁₀) ± SD on 7 dpv/0 dpcc (range)	Percent Positive for FMDV A24/Cruzeiro/BRA/55 VNT on 7 dpv/0 dpcc	Percent Protected from FMDV RNA in oral and nasal cavities (0–5 dpcc)	Percent Positive for FMDV NSP Antibodies
Treatment Group	N	Pedal only	Pedal and Oronasal				Percent Positive for FMDV NSP Antibodies
T1: 1^o vaccinated AdtA24 5 × 10¹⁰ PU (high dose) Contact Challenge	6	83%	50%	2.2 ± 0.2^a,b (1.8–2.4)	100%	0%	0% - 0 dpcc 67% - 14 dpcc
T2: 1^o vaccinated AdtA24 1.25 × 10¹⁰ PU (medium dose) Contact Challenge	6	100%	33%	1.5 ± 0.5^a (0.9–2.1)	100%	0%	0% - 0 dpcc 100% - 14 dpcc
T3: 1^o vaccinated AdtA24 3.125 × 10⁹ PU (low dose) Contact Challenge	6	67%	0%	1.1 ± 0.5^b (0.6–1.8)	67%	0%	0% - 0 dpcc 100% - 14 dpcc
T4: 1^o naïve Contact Challenge (control)	4	0%	0%	0.6 ± 0.0*	0%	0%	ND
T5 (IDL challenged seeder steers) 1 day prior to contact with T1-T4	8	0%	0%	0.6 ± 0.0*	0%	0%	ND

Dpcc days post contact challenge, DPV days post vaccination, VNT virus neutralization test, 1^o primary, PU particle units, IDL intradermolingual challenge, ND Not Determined
^*A positive VNT is ≥0.9 log₁₀. ^a, p = 0.01 for T1 > T2. ^b, p = < 0.001 for T1 > T3. p = 0.1 for T2 and T3

ISSN: 1746-6148