RAPID: Evaluating the potential for SARS-CoV-2 spillback infections of native North American wildlife

SARS-CoV-2病毒起源于蝙蝠，很可能在感染人类之前通过另一种动物传播。目的是确定两个北美本土野生动物物种是否可以感染新冠肺炎的病原体SARS-CoV-2，该病毒迄今尚未得到评估。臭鼬和浣熊与其他已知易感染这种病毒的物种关系密切，在人类环境中大量存在，经常食用人类排泄物。在野生动物研究和康复环境中，这两个物种也经常被处理--创造了病毒可能从人类溢出到它们身上的情况。此外，这项研究将调查臭鼬到臭鼬和浣熊到浣熊的传播是否可能，以预测如果这种病毒蔓延到我们当地的野生动物会发生什么；最糟糕的情况是，这些物种成为人类病毒的宿主。臭鼬和浣熊将接种两种剂量的SARS-CoV-2，这两种病毒代表它们可能遇到环境或与人密切接触时的剂量。接种后将采集鼻腔和粪便样本，并使用两种检测方法进行检测。还将每隔一段时间采集血液，以确定这些物种是否会产生针对病毒的抗体。除了将这一信息迅速传播给野生动物管理机构并公布结果外，这项工作还将培训三名研究生和两名本科生，内容涉及畜牧业、实验感染和各种实验室分析。这项研究的目标是确定两种北美本土野生动物物种--臭鼬和浣熊--是否容易感染SARS-CoV-2。目前的系统发育证据表明，新冠肺炎大流行是由动物宿主的溢出事件引发的，因此，了解动物物种的易感性至关重要。研究人员将评估临床结果、病毒脱落的持续时间和途径、血清转换和病理，以了解：1)这些常见且丰富的周围型哺乳动物野生动物物种的潜在储存状态，以及2)病毒从人类向这些物种蔓延的可能性。研究结果将指导采取主动行动，管理人、家畜和野生动物之间的接触--这对抗击正在进行的新冠肺炎大流行至关重要。动物将从圈养饲养员那里获得，并被安置在BSL3设施中。每一物种的三对将被接种两种剂量的SARS-CoV-2之一(103和105个菌斑形成单位)。为了确定直接接触传播，在接种后的第一天，我们将每对接种的动物中添加一只动物。接种后，将收集鼻拭子和直肠拭子进行qrtPCR和病毒分离，以及从接种和直接接触的动物身上采集血液样本，最长可达21天。兽医将每天监测所有动物的临床症状，并对其实施人道安乐死，从而进行全面的尸检。这一快速奖项是由综合组织系统生物部的生理和结构系统集群利用冠状病毒援助、救济和经济安全(CARE)法案的资金颁发的。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

SARS-CoV-2 originated from a bat, likely passing through another animal before it infected people. The objective is to determine if two North American native wildlife species can be infected with SARS-CoV-2, the causative agent of COVID-19, which to date has not been evaluated. Skunks and raccoons are closely related to other species that are known to be susceptible with this virus, and are highly abundant in human environments, frequently consuming human refuse. Both species are also handled frequently in wildlife research and rehabilitation settings—creating situations where spillback of the virus from people to them is likely. Further, this study will investigate whether skunk-to-skunk and racoon-to-raccoon transmission is possible, needed to forecast what would happen if this virus spilled into our native wildlife; the worst case scenario is that these species become reservoirs of the virus for people. Skunks and raccoons will be inoculated with two doses of SARS-CoV-2 that represent doses they might encounter the environment, or when in close contact with people. Nasal and fecal samples will be collected after inoculation and tested using two detection methods. Blood will also be collected at intervals to determine if these species create antibodies against the virus. In addition to rapidly disseminating this information to wildlife management agencies, presenting and publishing the results, this work will train three graduate and two undergraduate students on animal husbandry, experimental infections, and various laboratory analyses.The objective of this study is to identify if two North American native wildlife species that represent a high likelihood of susceptibility and ecological opportunity—skunks and raccoons—are susceptible to infection with SARS-Cov-2. Current phylogenetic evidence indicates a spillover event from an animal host prompted the COVID-19 pandemic, thus, understanding susceptibility of animal species is paramount. Researchers will assess clinical outcome, duration and route of virus shedding, and seroconversion and pathology to understand the: 1) potential reservoir status of these common and abundant, peridomestic, mammalian wildlife species and, 2) likelihood of virus spillover from humans to these species. Results will guide proactive actions to manage contact between humans, domestic animals and wildlife—crucial to combat the ongoing COVID-19 pandemic. Animals will be acquired from a captive breeder and housed in BSL3 facility. Three pairs of each species will be intranasally inoculated with one of two doses of SARS-CoV-2 (103 and 105 plaque forming units). To determine direct contact transmission, at Day 1 post-inoculation, we will add one animal to each pair of inoculated animals. Post-inoculation, nasal and rectal swabs for qrtPCR and virus isolation and blood samples from both inoculated and direct contact animals will be collected up to 21 days. All animals will be monitored for clinical signs daily by a veterinarian and humanely euthanized, whereby a complete post-mortem examination will be conducted. This RAPID award is made by the Physiological and Structural Systems Cluster in the BIO Division of Integrative Organismal Systems, using funds from the Coronavirus Aid, Relief, and Economic Security (CARES) Act.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.