对24例宠物临诊病例检测未发现新型冠状病毒（SARS-CoV-2）核酸阳性

2019新型冠状病毒(SARS-CoV-2)是一种在人体中新发现的冠状病毒,来源于野生动物。SARS-CoV-2属于冠状病毒科β冠状病毒属,而感染宠物犬猫类的冠状病毒主要来自α冠状病毒属。SARS-CoV-2是否感染犬、猫等宠物是当前抗击新冠肺炎疫情的重要公共卫生问题,也是大众关切的热点问题之一。本研究试图通过对有明晰腹泻和呼吸道症状的宠物犬和猫进行病原学检测,来阐明SARS-CoV-2是否感染宠物的科学问题,探究腹泻和呼吸症状宠物感染的普遍病因。本研究采用SARS-CoV-2的荧光定量PCR试剂和已经建立的诊断方法,对SARSCoV-2流行期间北京地区有腹泻和呼吸道症状的(特别是有发烧、严重咳嗽症状)临床宠物猫病例(20例)和宠物犬病例(4例)采集咽拭子,并进行SARS-CoV-2核酸荧光定量PCR检测和犬瘟热病毒(Canine distemper virus,CDV)、犬细小病毒(Canine parvovirus,CPV)、犬腺病毒Ⅱ型(Canine adenoviru-2,CAV-2)、犬副流感病毒(Canine parainfluenza virus,CPIV)、猫疱疹病毒I型(Feline herpesvirus-1,FHV-1)及猫杯状病毒(Feline calicivirus,FCV)、支原体(Mycoplasma,MY)及衣原体(Chlamydophila,CPS)等病原的检测。结果表明,所有样本SARS-CoV-2均为阴性,但分别存在其它病原感染。     

山东地区犬冠状病毒的分子流行病学调查及其基因型多样性分析

【目的】了解分析山东地区健康犬及腹泻犬中犬冠状病毒(CCoV)的分子流行病学及其基因型。【方法】采集2017年以来山东省宠物市场、流浪犬中心、犬舍、各地宠物医院等的健康和腹泻犬只的肛拭子样品,采用PCR方法检测CCoV及其CCoV-Ⅰ和CCoV-Ⅱ(CCoV-Ⅱa和CCoV-Ⅱb)基因分型情况,并对扩增出的M、S全基因进行测序分析。【结果】199份样品中,共检出CCoV阳性样品79份,健康犬中的检出率为40.2%(33/82),腹泻犬中的检出率为39.3%(46/117)。健康犬中CCoV-Ⅰ型与CCoV-Ⅱ型阳性检出率分别为78.8%(26/33)和51.5%(17/33);腹泻犬中CCoV-Ⅰ型与CCoV-Ⅱ型阳性检出率分别为39.13%(18/46)和80.4%(37/46)。基因型阳性比率分析表明,健康犬中单独感染CCoV-I型的比率最高,为48.5%(16/33);腹泻犬中单独感染CCoV-Ⅱa比率最高,为47.8%(22/46)。测序分析获得48株M基因序列,遗传进化分析表明,12株CCoV-Ⅰ型毒株中除1株外,其余均从健康犬中分离。36株CCoV-Ⅱ型毒株中除7株来自健康犬外,其余均为腹泻犬中获得。获得的3株S全基因均来自腹泻犬且均属于CCoV-Ⅱa亚型。【结论】山东地区犬群中CCoV检出率较高,说明CCoV广泛流行,健康犬和腹泻犬中均存在多重感染情况,健康犬中主要流行CCoV毒株为CCoV-Ⅰ型,腹泻犬中主要流行CCoV-Ⅱa型。     

SARS-CoV-2 NP和NP-FlaB融合蛋白的免疫原性研究

新型冠状病毒严重急性呼吸综合征冠状病毒2(SARS-CoV-2)感染引发的新型冠状病毒肺炎(COVID-19)疫情在全球持续流行,疫苗的研发和推广使用是阻止新冠疫情的关键手段.SARS-CoV-2核衣壳蛋白(NP)作为病毒的主要结构蛋白,是疫苗开发的潜在候选靶点.鞭毛素B(FlaB)可作为免疫佐剂,增强抗原的免疫原性....     

圈养小熊猫几种病毒的PCR检测

本文采用巢式PCR/ RT-PCR 方法,对我国10 个动物园中无临床症状的圈养小熊猫的71 个肛拭子和61 个唾液拭子样品,进行犬瘟热病毒(CDV)、犬细小病毒(CPV)、犬冠状病毒(CCV)、犬腺病毒(CAV)和犬疱疹病毒(CHV)的检测,以评估我国圈养小熊猫是否面临这几种病毒的威胁。对阳性PCR 结果进行测序分析,并与GenBank 上的序列进行比较。结果,在肛拭子样品中检测到3 个CPV 和6 个CCV 阳性结果,经测序后,与GenBank 上序列的同源性分别达99% 和100% 。而在唾液拭子样品中没有检测到任何阳性结果,且CDV、CAV和CCV 的检测结果均为阴性。从阳性CPV 的肛拭子样品中分离到一株细小病毒毒株,表明圈养小熊猫已受到细小病毒和犬冠状病毒的感染,今后应加强这两种病毒的预防工作。本文所采用的PCR 方法检测病毒性疾病,能检测到微量的病毒模板,可对小熊猫病毒性感染进行早期诊断。     

新型冠状病毒快速检测研究进展

当前全球大流行的新型冠状病毒肺炎(COVID-19)是由新型冠状病毒(SARS-CoV-2)感染的一种高传染性肺炎,其通过呼吸道飞沫、气溶胶、直接或间接接触、粪口传播或者冷链运输等途径在人群中进行传播,处在潜伏期或尚无明显症状的患者也具备传染他人的能力。SARS-CoV-2是一种有包膜的单股正链RNA病毒,拥有线性RNA片段,每个病毒粒子直径为60～140 nm。与其他冠状病毒相似,SARS-CoV-2主要包括4种结构蛋白,即：刺突蛋白(S)、膜蛋白(M)、包膜蛋白(E)和核衣壳蛋白(N)。迄今为止,基于病毒结构基础和病原学特点开发出了多种检测SARS-CoV-2的方法,为疑似COVID-19患者的确诊和疫情防控提供了有力的保障。简要介绍了SARS-CoV-2的病原学特征,并综述了核酸检测、免疫学检测和新型生物传感器等最新检测方法的研究进展,以期为COVID-19的早期诊断与防控提供帮助。     

新型冠状病毒致病机理及其疫苗的研发进展

新型冠状病毒(severe acute respiratory syndrome coronavirus-2, SARS-CoV-2)是一种可引起人新型冠状病毒肺炎(novel coronavirus pneumonia, NCP;亦称为COVID-19)的新发呼吸道病原体,与中东呼吸综合征冠状病毒(Middle East respiratory syndrome coronavirus, MERS-CoV)和严重急性呼吸综合征冠状病毒(severe acute respiratory syndrome coronavirus, SARS-CoV)同属β-冠状病毒,其受体与SARS-CoV的受体相同,均利用血管紧张素转化酶2(angiotensin-converting enzyme 2, ACE2)受体入侵人体细胞。SARS-CoV-2主要通过呼吸系统和消化系统感染,具有较高的传染性和致死率。目前,新冠病毒引起的肺炎已在全球范围内大规模蔓延,接种疫苗是根除病毒性传染病最有效的方法,国内外各大科研机构已快速展开COVID-19疫苗的研制工作,这是有效控制疫情的重点和难点。现就新冠病毒的致病机理、感染途径及疫苗研发作一综述,旨在为相关研究人员提供参考。     

对383份鸟类样品检测未发现SARS-CoV-2阳性

2019年12月以来,全球大面积发现了由新型冠状病毒(SARS-CoV-2)引起的新型冠状病毒肺炎(COVID-19)疫情,病毒溯源一直是研究的重点。目前在畜禽和毛皮动物中均未检测出病原,而关于SARS-CoV-2在珍禽和濒危候鸟的溯源性研究至今尚未报道。本研究收集了2019-2020年吉林省内绿头鸭、白羽鸭、雉鸡、鸿雁、白天鹅等10种珍禽和濒危候鸟的咽拭子、肛拭子和粪便样品共383份。通过WHO推荐Real-time RT-PCR方法对上述样品中SARS-CoV-2进行检测。结果显示,383份样品中SARS-CoV-2核酸检测结果均为阴性。     

新型冠状病毒肺炎感染病例中鼻咽拭子与咽拭子标本的病毒核酸检验结果分析

新型冠状病毒(SARS-CoV-2)主要通过飞沫和密切接触传播,传染性强,目前在全球蔓延,给人的身体健康及世界公共卫生安全造成了严重的损害。病毒核酸检验是新型冠状病毒肺炎(COVID-19)病例确诊的金标准。本研究分别采集武汉江夏方舱医院67例确诊为COVID-19病例的鼻咽拭子与咽拭子标本送检,进行SARS-CoV-2核酸检验。其中28例患者鼻咽拭子病毒核酸呈阳性,13例患者咽拭子病毒核酸呈阳性,26例患者鼻咽拭子与咽拭子病毒核酸均为阴性。本研究结果提示,鼻咽拭子送检标本病毒核酸检验结果优于咽拭子标本(P<0.05)。     

冠状病毒对天然免疫的抑制作用

由严重急性呼吸综合征冠状病毒2(severe acute respiratory syndrome coronavirus 2, SARS-CoV-2)引起的新型冠状病毒肺炎(corona virus disease 2019, COVID-19),至今仍在全球范围内流行。21世纪以来,数次冠状病毒感染疫情促使人类更加重视冠状病毒,尤其是COVID-19疫情的暴发与大流行,更将新冠病毒提升为全球的研究重点。免疫反应与病毒的感染、清除以及病理损伤等密切相关。天然免疫是机体防御体系的重要组成部分和首道防线,在病毒感染早期对于抑制病毒的复制和扩散具有至关重要的作用,并且在获得性免疫的启动及后续的发展中也发挥着关键的调控功能。研究表明,免疫逃逸是冠状病毒的重要致病机制,冠状病毒能够通过多种方式抑制宿主的天然免疫应答。现对SARS-CoV-2等主要的冠状病毒抑制天然免疫的分子机制作一概述,以期为抗冠状病毒感染的疫苗及治疗性药物的研发提供帮助。     

SARS-CoV-2与SARS-CoV:病原学、流行病学、临床与病理

2019年12月在武汉暴发了由SARS-CoV-2感染引起的新型冠状病毒肺炎(Coronavirus disease 2019,COVID-19),并迅速扩散至全国.SARS-CoV-2和SARS冠状病毒(SARS-CoV)都属于套式病毒目、冠状病毒科、冠状病毒属中的SARS相关冠状病毒种,本文总结了两者在来源、病毒结构、流行病学、临床表现和病理学特征等方面的差异,以期更全面认识SARS-CoV和SARS-CoV-2,为COVID-19的防治研究提供帮助.     

Genetic and antigenic characterization of recombinant nucleocapsid proteins derived from canine coronavirus and canine respiratory coronavirus in China

To characterize the antigenicity of nucleocapsid proteins (NP) derived from canine coronavirus (CCoV) and canine respiratory coronavirus (CRCoV) in China, the N genes of CCoV (CCoV-BJ70) and CRCoV (CRCoV-BJ202) were cloned from swabs obtained from diseased pet dogs in Beijing and then sequenced. The recombinant NPs (rNPs) were expressed in Escherichia coli and purified by nickel-affinity column and size exclusion chromatography. Sequencing data indicated that the N genes of CCoV-BJ70 and CRCoV-BJ202 belonging to two distinctly different groups were relatively conserved within each subgroup. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) results showed that rNPs of CCoV and CRCoV were expressed efficiently and isolated with a final purity of over 95%. Western blot analysis revealed the rNP from CRCoV could cross-react with mice antisera against human coronavirus (HCoV-229E, NL63, OC43, HKU1), while rNP of CCoV had cross-reactivity with only anti-sera against viruses belonging to the same group (HCoV-229E and NL63). In summary, CCoV and CRCoV rNPs were successfully expressed in E. coli and showed antigenic cross-reactivity with antisera raised against human coronaviruses. These findings indicate that further serologic studies on coronavirus infections at the animal-human interface are needed.     

Evaluation of antibody response to canine coronavirus infection in dogs by Western Blotting analysis

We investigated by Western Blotting the antibody responses against the three major structural proteins of Canine coronavirus (CCoV) in dogs naturally infected. A pool of Elisa positive sera were also tested to clearly identify the binding profiles of CCoV proteins. The immune response to S protein was barely detectable in naturally infected dogs, whereas anti-M and anti-N antibodies were detected with a very strong reaction and for a long time post infection. The limited response to S protein may explain the poor protection of dogs and the possibility of persisting infection.     

Severe Acute Respiratory Syndrome Coronavirus 2: Manifestations of Disease and Approaches to Treatment and Prevention in Humans

The coronavirus disease 2019 (COVID-19) pandemic was caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus has challenged civilization and modern science in ways that few infectious diseases and natural disasters have previously, causing globally significant human morbidity and mortality and triggering economic downturns across financial markets that will be dealt with for generations. Despite this, the pandemic has also brought an opportunity for humanity to come together and participate in a shared scientific investigation. Clinically, SARS-CoV-2 is associated with lower mortality rates than other recently emerged coronaviruses, such as SARS-CoV and the Middle East respiratory syndrome coronavirus (MERS-CoV). However, SARS-CoV-2 exhibits efficient human-to-human spread, with transmission often occurring before symptom recognition; this feature averts containment strategies that had worked previously for SARS-CoV and MERS-CoV. Severe COVID-19 disease is characterized by dysregulated inflammatory responses associated with pulmonary congestion and intravascular coagulopathy leading to pneumonia, vascular insults, and multiorgan disease. Approaches to treatment have combined supportive care with antivirals, such as remdesivir, with immunomodulatory medications, including corticosteroids and cytokine-blocking antibody therapies; these treatments have advanced rapidly through clinical trials. Innovative approaches to vaccine development have facilitated rapid advances in design, testing, and distribution. Much remains to be learned about SARS-CoV-2 and COVID-19, and further biomedical research is necessary, including comparative medicine studies in animal models. This overview of COVID-19 in humans will highlight important aspects of disease, relevant pathophysiology, underlying immunology, and therapeutics that have been developed to date.

In December 2019, a cluster of cases of pneumonia without a clear etiology occurred in Wuhan, China. With remarkable speed and efficiency, the etiology of this illness was soon identified as a novel coronavirus; the complete viral genome was sequenced and published on January 10, 2020.¹⁸² These events introduced the world to coronavirus disease 2019 (COVID-19). The disease, now known to be caused by a novel coronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has developed into the most significant pandemic of recent times. In less than a year since the virus was first recognized, multiple candidate vaccines were developed worldwide, and some of them rapidly progressed to clinical trials and widespread administration. As the pandemic continues, a number of sequence variants of the virus have emerged around the world. This continued viral evolution highlights the need for continued biomedical research to facilitate understanding of the pathogenesis of COVID-19, seeking innovative therapeutic and preventative strategies for the current and possibly future pandemics. This article will review aspects of SARS-CoV-2 infection of humans and COVID-19, focusing on important aspects of clinical disease, pathophysiology, immunology, and the development of therapeutic and preventative measures to provide context for discussion of the animal models used to study SARS-CoV-2 and COVID-19.     

No Evidence of SARS-CoV-2 Infection in Neotropical Primates Sampled During COVID-19 Pandemic in Minas Gerais and Rio Grande do Sul,Brazil

EcoHealth - In 2019, a new coronavirus disease (COVID-19) was detected in China. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was capable to infect domestic and captive mammals like...     

A Comprehensive Review of Animal Models for Coronaviruses: SARS-CoV-2, SARS-CoV,and MERS-CoV

The recent outbreak of coronavirus disease(COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has already affected a large population of the world. SARS-CoV-2 belongs to the same family of severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome coronavirus(MERSCoV). COVID-19 has a complex pathology involving severe acute respiratory infection, hyper-immune response, and coagulopathy. At present, there is no therapeutic drug or vaccine approved for the disease. There is an urgent need for an ideal animal model that can reflect clinical symptoms and underlying etiopathogenesis similar to COVID-19 patients which can be further used for evaluation of underlying mechanisms, potential vaccines, and therapeutic strategies. The current review provides a paramount insight into the available animal models of SARS-CoV-2, SARS-CoV, and MERS-CoV for the management of the diseases.     

Clinical characteristics of 310 SARS-CoV-2 Omicron variant patients and comparison with Delta and Beta variant patients in China

Although the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant has spread, data on the clinical characteristics of infected patients are limited. In this study, the demographic, clinical characteristics, and laboratory data of 310 SARS-CoV-2 Omicron variant patients treated at Haihe Hospital of Tianjin were collected and analyzed. Information on these patients was compared to 96 patients with the Delta variant of concern (VOC) and 326 patients with the Beta VOC during the previous coronavirus disease 2019 (COVID-19) outbreak in Harbin. Of the 310 patients infected with the Omicron variant, the median age was 35 years. Most patients were clinically classified as mild (57.74%), and the most common symptoms were cough (48.71%), fever (39.35%), and sore throat (38.26%). The results for different vaccination groups in the Omicron group showed that the median of “SARS-CoV-2 specific IgG” after 2 or 3 doses of vaccination was higher than the unvaccinated group (all Ps < 0.05). Older age was associated with a higher proportion of moderate cases and lower asymptomatic and mild cases based on clinical classifications. Compared to the Delta and Beta groups, the median age of the Omicron group was younger. The total number of asymptomatic patients and mild patients in the Omicron virus group was higher than the Delta and Beta groups (60.97% vs. 54.17% vs. 47.55%). This study presented the clinical characteristics of the first group of patients infected with the Omicron variant in Tianjin, China, and compared their clinical features with patients infected by the Delta and Beta variants, which would increase our understanding of the characteristics of SARS-CoV-2 Omicron variant.