Kinetics of rabies antibodies as a strategy for canine active immunization

Background Rabies, a zoonosis found throughout the globe, is caused by a virus of theLyssavirus genus. The disease is transmitted to humans through the inoculation of the virus present in the saliva of infected mammals. Since its prognosis is usually fatal for humans, nationwide public campaigns to vaccinate dogs and cats against rabies aim to break the epidemiological link between the virus and its reservoirs in Brazil.Findings During 12 months we evaluated the active immunity of dogs first vaccinated (booster shot at 30 days after first vaccination) against rabies using the Fuenzalida-Palácios modified vaccine in the urban area of Botucatu city, São Pauto state, Brazil. Of the analyzed dogs, 54.7% maintained protective titers (≥0.5 IU/mL) for 360 days after the first vaccination whereas 51.5% during all the study period.Conclusions The present results suggest a new vaccination schedule for dogs that have never been vaccinated. In addition to the first dose of vaccine, two others are recommended: the second at 30 days after the first and the third dose at 180 days after the first for the maintenance of protective titers during 12 months.

背景：狂犬病是一种全球分布的人兽共患病，由狂犬病病毒属（Lyssavirus）的病毒引发。该疾病可通过感染哺乳动物唾液中的病毒侵入人体而传播给人类。由于人类感染狂犬病后的预后通常为致死性，巴西全国性的猫狗狂犬病疫苗接种公益行动旨在切断该病毒与巴西境内病毒储存宿主之间的流行病学联系。
研究结果：在为期12个月的研究中，我们于巴西圣保罗州博图卡图市城区，采用Fuenzalida-Palácios改良疫苗，对首次接种狂犬病疫苗（首剂接种后30天接受加强免疫）的犬只的主动免疫水平进行了评估。经分析的犬只中，54.7%的个体在首剂接种后360天内仍维持保护性抗体滴度（≥0.5 IU/mL），另有51.5%的个体在整个研究周期内均保持该滴度水平。
结论：本研究结果为未接种过狂犬病疫苗的犬只提出了全新的免疫程序：除首剂疫苗外，推荐追加两剂加强免疫——第二剂于首剂接种后30天接种，第三剂于首剂接种后180天接种，以此维持12个月的保护性抗体滴度。