Leelahapongsathon Kansuda, Kasemsuwan Suwicha, Pinyopummintr Tanu, Boodde Orawan, Phawaphutayanchai Parinya, Aiyara Nirut, Bobe Katharina, Vos Ad, Friedrichs Virginia, Müller Thomas, Freuling Conrad M, Chanachai Karoon
Faculty of Veterinary Medicine, Kasetsart University, Bangkok 10900, Thailand.
Department of Health, Bangkok Metropolitan Administration, Thapthan 61120, Thailand.
Vaccines (Basel). 2020 Oct 1;8(4):573. doi: 10.3390/vaccines8040573.
Applied research is crucial in pushing the boundaries and finding a solution to the age-old problem of dog-mediated rabies. Although oral vaccination of dogs is considered to have great potential in mass dog vaccination campaigns and could have far-reaching benefits, it is perhaps the most ignored of all available tools in efforts to eliminate dog-mediated rabies, not least because of limited data on immunogenicity, efficacy, and safety of potential oral rabies vaccine candidates. In this study, the long-term immunogenicity in local Thai dogs after oral administration of the highly attenuated 3rd generation rabies virus vaccine strain SPBN GASGAS was assessed. The oral rabies vaccine was administered to dogs by either direct oral administration ( = 10) or by offering a vaccine loaded intestine bait ( = 15). The humoral immune response was then compared to three groups of dogs; a group that received a parenteral delivered inactivated rabies vaccine ( = 10), a group offered a placebo intestine bait ( = 7), and a control group ( = 4) for an observation period of 365 days. There was no significant difference in the immune response of dogs that received oral and parenteral vaccine in terms of magnitude, kinetics, and persistence of both rabies virus (RABV) neutralizing (RFFIT) and binding (ELISA) antibodies. Although the single parenteral injection of an inactivated rabies vaccine mounted a slightly higher humoral immune response than the orally delivered live vaccine, RABV specific antibodies of both types were still detectable after one year in most animals for all treatment groups and resulted in no difference in seropositivity. Characterization of rabies specific antibodies revealed two main classes of antibodies involved in the immune response of dogs vaccinated. While IgM antibodies were the first to appear, the succeeding IgG response was mainly IgG2 dominated independent of the vaccine type used. The results support the view that SPBN GASGAS induces a sustained detectable immune response in local dogs both after direct oral administration and via bait application.
应用研究对于突破界限、找到解决由犬介导的狂犬病这一古老问题的方法至关重要。尽管犬只口服疫苗在大规模犬类疫苗接种活动中被认为具有巨大潜力，且可能带来深远益处，但在消除犬介导的狂犬病的努力中，它或许是所有可用工具中最被忽视的，尤其是因为关于潜在口服狂犬病疫苗候选株的免疫原性、效力和安全性的数据有限。在本研究中，评估了口服高度减毒的第三代狂犬病病毒疫苗株SPBN GASGAS后，泰国本地犬的长期免疫原性。通过直接口服（n = 10）或提供装有疫苗的肠饵（n = 15）的方式给犬只接种口服狂犬病疫苗。然后将体液免疫反应与三组犬只进行比较；一组接受肌肉注射灭活狂犬病疫苗（n = 10），一组提供安慰剂肠饵（n = 7），以及一个对照组（n = 4），观察期为365天。在狂犬病病毒（RABV）中和（RFFIT）抗体和结合（ELISA）抗体的强度、动力学和持久性方面，接受口服和肌肉注射疫苗的犬只的免疫反应没有显著差异。尽管单次肌肉注射灭活狂犬病疫苗产生的体液免疫反应略高于口服活疫苗，但在所有治疗组中，大多数动物在一年后仍可检测到两种类型的RABV特异性抗体，且血清阳性率没有差异。狂犬病特异性抗体的特征表明，参与接种疫苗犬只免疫反应的主要有两类抗体。虽然IgM抗体最先出现，但随后的IgG反应主要以IgG2为主，与所使用的疫苗类型无关。结果支持了这样一种观点，即SPBN GASGAS在直接口服给药和通过饵剂应用后，均可在本地犬只中诱导持续可检测的免疫反应。
