Fig. 2.

Vaccine immunogenicity and efficacy in pregnant ewes and does. Rectal temperatures, serological responses (RVFV VNT₅₀ titres, anti-N ELISA) and viraemia following vaccination and challenge of pregnant ewes and goats are shown. Data in a, c, e and g are from pregnant ewes, whilst data in b, d, f and h are from pregnant does. Vaccination and challenge were performed as shown in Fig. 1. The black arrows represent the day of challenge. Anti-N ELISA titres (e and f) are expressed as percentage inhibition calculated as ratio of the optical densities (OD) of the sample and the OD of the negative control (% S/N) as per manufacturer’s instructions. All values lower than 40% are considered positive, between 40% and 50% are considered doubtful and above 50% are considered negative. The dotted lines represent the 40% and 50% inhibition. Samples that tested negative for viraemia are depicted at the detection limit of the RT-qPCR assay (1.3 log10 RNA copies/ml). All data are depicted as means and standard errors. p Values from Mann–Whitney U test comparing pre-challenge VNT₅₀ titres (as measured on day 21; c and d) and viraemia levels at 3 days post-challenge (g and h) between mock- and ChAdOx1 RVF-vaccinated animals are shown; ***p < 0.001