Safety, efficacy and immunogenicity evaluation of the SAG2 oral rabies vaccine in Formosan ferret badgers

Abstract

Since 2013, rabies cases have been reported among Formosan ferret badgers in Taiwan, and they have been shown to be the major reservoirs for Taiwanese enzootics. To control and eradicate rabies, the authorities plan to implement a vaccination programme. Before distributing live vaccines in the field, this study assessed the safety, efficacy, and immunogenicity of SAG2 vaccine on ferret badgers by direct oral instillation. After application of 109 TCID50/dose, no virus was excreted into the oral cavity 1–7 days post-application, and safety was also satisfactorily verified over a 266-day period. Moreover, despite the low level of rabies virus neutralising antibodies induced after vaccination of a 108 TCID50/dose, the efficacy assessment revealed a 100% survival rate (15/15) of vaccinees and an 87.5% fatality rate (7/8) in control animals after a challenge on the 198th day post-vaccination. The immunisation and protection rates obtained more than 6 months after a single vaccination dose demonstrated that SAG2 is an ideal vaccine candidate to protect Formosan ferret badgers against rabies in Taiwan.

Comparable Long-Term Rabies Immunity in Foxes after IntraMuscular and Oral Application Using a Third-Generation Oral Rabies Virus Vaccine

“…Consistent with previous reports [ 12 , 15 , 20 , 21 , 41 ], we demonstrate comparable long-term (365 dpv) rabies immunity in foxes after intramuscular and oral application using a third-generation oral rabies virus vaccine, i.e., SPBN GASGAS. The humoral immune response resembles those reported in previous studies with the same and other modified live virus vaccines ( Figure 1 ) [ 18 , 19 , 20 , 48 , 52 , 53 , 54 , 55 ]. With the exception of two animals, there was no difference in binding antibody ( Figure 1 B,D) and VNA response ( Figure 1 A,C) between both vaccinated groups.…”

Long-Term Immunogenicity and Efficacy of the Oral Rabies Virus Vaccine Strain SPBN GASGAS in Foxes

“…The results proved the induction of a specific immune response at three weeks p.v., which remained at a very high level up to 12 months p.v. The strong increase in rabies antibody levels immediately after challenge was the result of a booster effect to the challenge virus (Figure 1), as also observed in other efficacy studies [67,74,79,80]. In other studies, no indication of a booster effect after administration of the challenge virus could be found [68,69].…”

Using phylogeographic approaches to analyse the dispersal history, velocity and direction of viral lineages — Application to rabies virus spread in Iran

“…Understanding the key sources responsible for rabies epizootics and identifying host switches can have concrete implications on the implementation of rabies control measures in animals, as well as on the strategy of animal vaccination towards the ultimate goal of elimination (Fusaro et al, 2013;Un et al, 2012). In fact, rabies vaccination in wildlife requires specific strategies and stakeholder involvement (Freuling et al, 2013, Hsu et al, 2017, Müller et al, 2015, Wallace et al, 2018, which are different from those applied for infected dogs (Fahrion et al, 2017;Lembo, 2012). In Iran and the Middle East, rabies has been reported in many wild carnivore species such as foxes, golden jackals, wolves and martens (Janani et al, 2008;Picot et al, 2017;Seimenis, 2008).…”