狂犬病病毒
狂犬病病毒，属Lyssavirus, is a vaccine-preventable, zoonotic, viral disease present on all continents except Antarctica. Rabies infects all mammals and has the案件死亡率最高of any infectious disease, with over 95% of human deaths occurring in the Asia and Africa regions. In humans, rabies is a被忽视的热带疾病that predominantly affects poor and vulnerable populations living in remote rural locations.
Rabies infections are typically transmitted through thebite of a rabid animal。The incubation period is typically 2–3 months, but may vary from 1 week to 1 year, dependent upon factors such as location of virus entry and viral load.Initial symptomsof rabies include fever with pain and an unusual tingling, pricking or burning sensation (paraesthesia) at the wound site. As the virus spreads to the central nervous system (CNS), progressive and fatal inflammation of the brain and spinal cord develops. Infections that reach the CNS are almost invariably lethal in both natural reservoirs, such as bats and carnivores, and accidental hosts, such as livestock and人类。
狂犬病病毒中和抗体
Interestingly, some exposures to rabies lead to the production of rabies virus neutralizing antibodies (RVNAs).RVNAs clear the infectionbefore the virus invades the CNS and causes neurological symptoms. These “abortive infections” occur predominately in蝙蝠但两者都可以广泛水库和非储藏主机。
广泛的流产RABV感染开辟了使用非储库物种中血清学研究的可能性，以补充现有的监视系统。非储库宿主监视可能比对水库的监视更实用，涉及昂贵的捕获和抽样，并且比被动死亡率的被动报告更可靠。
In Latin America,普通吸血鬼蝙蝠(Desmodus rotundus) are the primary source of rabies. However, livestock and human death reporting efforts在地理上有所不同。在最近在秘鲁南部进行的一项研究中贝纳维德斯和同事aimed to identify animals among five livestock species with abortive infections and determine whether seropositivity correlates with rabies mortality in livestock recorded through passive surveillance.
Abortive rabies infections in Peruvian livestock
Between May and June 2016, livestock sampling was conducted in Apurimac, Ayacucho and Cusco, Peru, which together account for almost 70% of rabies cases in Peruvian livestock. Rabies vaccination of cattle varies considerably while sheep and goats are rarely vaccinated.
Serology was performed on serum samples from 305 animals in 13 districts (92% of samples). All animals were healthy during sampling and questionnaires confirmed the lack of recent illness. None of the animals were vaccinated prior to samples. Of the 305 animals sampled, 23 were seropositive with titers >0.10 UL/mL:
- Overall seroprevalence (n/N = 23/305): 7.5% (95% CI: 5–11)
- Cattle seroprevalence (n/N = 19/173): 11% (95% CI: 7–17)
- Goat seroprevalence (n/N = 3/60): 5% (95% CI: 1–15)
- 绵羊血清阳性（N/N = 1/28）：4％（95％CI：0–20）
- 马（N/N = 0/39）：0％
- Pigs (n/N = 0/5): 0%
阳性动物的滴度范围为0.12至70 IU/mL。五个农场有多个血清阳性动物。大约三分之一（12/35）采样的社区至少有一种血清阳性动物。最初样品两年后的后续活动证实，没有任何血清阳性动物死于狂犬病。
总体而言，有92％的采样动物提供了吸血鬼蝙蝠咬伤的证据。所有动物中有56％观察到新鲜的叮咬，而77％的动物有较早的叮咬证据。女性（55％）和男性（58％）以及年龄较大的动物（56％）和年轻（58％）的新鲜叮咬频率相似。动物的年龄或性别都不与血清学状况相关。
尽管早些时候发生了爆发，但在样本收集前的12个月中，只有一个有血清阳性动物的社区在一个地区（大约）没有确认的狂犬病。在从未报道过狂犬病的卡亚帕地区没有发现血清反应阳性的动物。研究人员还发现，在抽样前一年报告的病例数量显着增加了血清阳性的可能性。在抽样前或采样后6个月报告的病例数以及抽样后一年报告的病例数也显着增加了血清阳性的可能性。
结论
In the recent study,贝纳维德斯和同事发现未接种疫苗的牛，山羊和绵羊经常被吸血鬼蝙蝠咬伤，可检测到可检测到的RVNA水平，并在采样后至少保持健康两年。堕胎感染与报告的牲畜死亡率的相关性突出了使用牲畜血清学与蝙蝠中狂犬病循环水平的大致水平的可能性。它还首次证明，仅狂犬病死亡率报告并不能完全表征从蝙蝠到牲畜的病毒暴露率。更多的研究以更好地了解流产感染的基础将有助于解决狂犬病生物学内部知识的这一差距。
注释