警惕冠状病毒经眼传播

目前新型冠状病毒肺炎(COVID-19)疫情在中国湖北武汉快速传播,并引起了国际社会的广泛关注。目前有线索认为结膜可能是新型冠状病毒(SARS-CoV-2)感染的入口之一。但目前缺乏SARS-CoV-2眼部感染的临床观察资料,因此了解冠状病毒经眼传播的机制和细胞受体,了解其他同源病毒感染眼部的传播特征,有助于眼科医生在COVID-19防控工作中采取合理防护措施并及时识别与眼部体征并存的COVID-19。     

关注新型冠状病毒肺炎与眼表传播问题

自2019年岁末以来,新型冠状病毒感染的肺炎(COVID-19)疫情在中国武汉快速传播并引起中国和国际社会的广泛关注。目前已有尚未确认的线索认为结膜可能是新型冠状病毒(SARS-CoV-2)感染的通道之一,因此关于COVID-19感染方式以及SARS-CoV-2是否通过眼表组织进行传播的问题也成为新的关注点。由于目前尚缺乏SARS-CoV-2在眼部感染的临床观察资料和实验室研究证据,因此对引起流行性疾病的病毒引起眼部病变的部分文献进行回溯和分析则更有助于我们在COVID-19疫情防控过程中对眼部及相应的工作环境和器械采取合理的防护措施。     

SARS-CoV-2对眼部的影响及其经眼途径传播的可能性

SARS-CoV-2引起的新型冠状病毒肺炎（COVID-19）已对全球构成重大的公共卫生威胁。SARS-CoV-2和SARS-CoV均属于人冠状病毒（HCoVs）β属,两者的基因组相似性高达79.6%,且均通过血管紧张素转换酶2（ACE-2）感染宿主细胞。目前已有研究表明,SARS-CoV-2感染与结膜炎具有一定相关性,SARS-CoV-2是否能经眼感染或传播的问题也备受关注,但目前尚缺乏其通过眼部组织感染的临床确诊病例和实验室证据。本文就SARS-CoV-2的病原学特点、流行病学特征、眼部表现及结膜囊病毒感染率作一综述,并对SARS-CoV-2经眼途径传播的可能性进行探讨。     

新型冠状病毒感染及其疫苗接种相关的眼科疾病

由新型冠状病毒(严重呼吸综合征-冠状病毒-2型,SARS-CoV-2)引起的新型冠状病毒肺炎(COVID-19),因其极高的传染致病性,严重威胁人类的生命健康,同时也给目前的医疗模式带来全新挑战。已有众多文献资料显示SARS-CoV-2感染不仅可以造成肺脏、肾脏、肠道等全身损害,而且也能累及眼组织,从较为常见的眼表疾病如角膜、结膜、巩膜炎症,到相对少见的旁中心急性中层黄斑病变和急性黄斑神经视网膜病变。对以眼部症状为首发或伴随症状的SARS-CoV-2感染患者而言,眼科医生如何甄别眼部表现与SARS-CoV-2感染之间的相关性无疑面临严峻的挑战。本文将结合近年相关文献,探讨由SARS-CoV-2感染和接种新型冠状病毒肺炎疫苗所引起的相关眼部病变,涵盖了眼表、葡萄膜、视网膜和黄斑以及颅神经等病理改变。     

从SARS冠状病毒探讨新型冠状病毒眼途径传播的可能机制

新型冠状病毒(SARS-CoV-2)自2019-12爆发以来,传播速度极快,了解其流行病学特征,尤其是切断传播途径对于控制疾病传播至关重要。在传播途径的研究中,SARS-CoV-2是否通过眼表组织进行传播的问题也引起关注,但目前尚缺乏其通过眼表组织感染的临床确诊病例和实验室证据。最新研究认为SARS-CoV-2与SARS冠状病毒(SARS-CoV)属于同一种属,并且其与SARS-CoV进入细胞的途径是一样的。本文通过回顾SARS-CoV的研究,探讨SARS-CoV-2眼途径传播的可能机制。     

新型冠状病毒肺炎的眼部表现

新型冠状病毒肺炎(coronavirus disease 2019,COVID-19,新冠肺炎)是由新型冠状病毒(novel coronavirus,SARS-CoV-2,新冠病毒)引起的一种具有高度传染性的疾病,目前在世界各地广泛流行,并引起全球性恐慌。研究表明,新冠病毒可以通过眼部黏膜传播,因此眼科医务人员更容易受到感染。新冠肺炎患者眼部表现主要累及结膜、角膜、巩膜、前房、瞳孔、视网膜、视神经和视皮层、眼外肌及其颅神经支配、眼眶和泪器系统等。病毒性结膜炎是新冠肺炎患者最常见的眼部表现。新冠肺炎流行期间,为了眼科医务人员免受感染,安全地开展临床工作,本文依据近年来相关文献报道总结了新冠肺炎的眼部表现,主要包括流行病学、病理生理、临床表现等方面。     

充分认识COVID-19相关眼部损害, 努力提高诊疗水平

由严重急性呼吸综合征冠状病毒2型(SARS-CoV-2)引起的新型冠状病毒感染(COVID-19)在全球持续大流行, 给全球医疗模式带来了深刻影响, 更多积累的、新的医学资料提示SARS-CoV-2感染会侵犯患者多个器官, 但对其引起的眼部相关病变特征及其危害仍缺乏足够认识。已有的临床资料发现, COVID-19相关眼病主要包括眼表炎性病变和眼后节的视网膜、脉络膜病变, 疾病不仅表现为急性炎性反应过程, 还可导致视网膜和脉络膜的微血管栓塞性病理过程, 给患者, 尤其是首诊为眼科的患者视力预后可能带来长期影响, 准确诊断COVID-19相关眼病是眼科医生面临的挑战。眼科医生应深入了解SARS-CoV-2感染者眼病相关疾病的发生机制和发展规律, 利用目前的眼科多模式影像检查以减少患者相关眼部疾病的漏诊和误诊, 及时采取针对性治疗措施, 尽可能降低疾病对视功能损害的风险。建议眼科临床工作者开展相关疾病的发病机制研究及多学科临床研究, 以降低COVID-19相关眼病患者的致盲率, 改善患者的生活质量。     

新型冠状病毒肺炎疫情期间眼科急诊及手术的防控策略

新型冠状病毒(SARS-CoV-2)感染的肺炎,新型冠状病毒肺炎(COVID-19)已被中国列为按照甲类传染病管理的乙类传染病,由医院相关性传播导致的COVID-19并不少见,给临床医护人员和住院患者造成严重威胁。本文介绍眼科医生应掌握COVID-19的流行病学特点和临床表现,眼科医生如何应对眼科急诊患者,围绕眼科急诊及手术的感染防控要点和加强具体防控措施,为战疫在一线的眼科医护感染防控提供参考。     

严重急性呼吸综合征冠状病毒2型（SARS-CoV-2）眼表感染研究进展

严重急性呼吸综合征冠状病毒2型（SARS-CoV-2,又称COVID-19）经眼表传播远较经口鼻传播困难,然而现有证据认为眼表传播仍是一条可能的途径,尤其对于医护人员。本文描述了SARS-CoV-2相关的眼表症状,阐释了眼表SARS-CoV-2入胞的可能机制和与眼表相关的SARS-CoV-2传播机制,并对现有的和未来可能的研究方向进行了剖析,为从眼表考虑临床治疗SARS-CoV-2提供新的思路与方法,帮助人们研发出更多的治疗策略。     

新型冠状病毒防控中眼科医务人员的预防措施

目前新型冠状病毒(SARS-CoV-2)感染的疫情进入了一个关键期。截止2020-02-14,全国已有超过55000例新型冠状病毒感染确诊病例,给社会和经济带来极大影响,也极大地影响了眼科的日常运作。本文针对眼科门诊及病房所需的医务防护措施进行讨论和建议,以期减少在SARS-CoV-2爆发期眼科医护人员的感染。     

Retinal vein occlusion in COVID-19: A novel entity

Coronavirus disease 2019 (COVID-19) is a form of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) that has been declared a pandemic by the World Health Organization (WHO). Ocular manifestations related to COVID-19 are uncommon with conjunctivitis being reported in a few cases. We report a unique case of vasculitic retinal vein occlusion (RVO) secondary to COVID-19 in a 52-year-old patient who presented with the diminution of vision in the left eye 10 days after he tested positive for SARS-CoV-2. All investigations for vasculitis were negative. This case supports the mechanism of thrombo-inflammatory state secondary to the “cytokine-storm” as the pathogenesis for systemic manifestations of COVID-19.     

The evidence of SARS-CoV-2 infection on ocular surface

This is a cross-sectional study of patients who received a COVID-19 diagnosis between December 30, 2019 and February 7, 2020 at Tongji Hospital. A total of 102 patients (48 Male [47%] and 54 Female [53%]) with clinical symptoms, Rt, and chest Computed Tomography (CT) abnormalities were identified with a clinical diagnosis of COVID-19. Patients had a mean [SD] gestational age of 57.63 [14.90] years. Of a total of 102 patients identified, 72 patients (36 men [50%] and 36 women [50%]; mean [SD] age, 58.68 [14.81] years) were confirmed to have COVID-19 by laboratory diagnosis with a SARS-CoV-2 RT-PCR assay. Only two patients (2.78%) with conjunctivitis were identified from 72 patients with a laboratory confirmed COVID-19. Of those two patients, SARS-CoV-2 RNA fragments were found in ocular discharges by SARS-CoV-2 RT-PCR in only one patient. Our findings suspect the incidence of SARS-CoV-2 infection through the ocular surface is extremely low, while the nosocomial infection of SARS-CoV-2 through the eyes after occupational exposure is a potential route. To lower the SARS-CoV-2 nosocomial infection, all health care professionals should wear protective goggles. The inefficient diagnostic method and the sampling time lag may contribute to the lower positive rate of conjunctival swab samples of SARS-CoV-2.     

Detection of SARS-CoV-2 RNA in a conjunctival swab sample in real-time-polymerase chain reaction positive COVID-19 patients and its association with comorbidity and severity at a designated COVID-19 hospital in Central India

Purpose:To evaluate the presence of SARS-CoV-2 RNA in the conjunctival swab sample of positive confirmed COVID-19 patients and to find out its association with comorbidity and severity of COVID-19 disease.Methods:We conducted an observational cross-sectional study at a dedicated tertiary COVID-19 hospital in central India for a period of 8 weeks from February 2021to March 2021. We included patients who tested positive for SARS-CoV-2 RNA through nasopharyngeal swab and were above 18 years of age. Swab samples have been collected within 48 h of admission. Conjunctival swab was taken from the lower fornix of both eyes and sent to microbiology laboratory for real-time- polymerase chain reaction (RT-PCR).Results:Out of 150 patients, conjunctival swab RT-PCR was positive in five patients (3.33%). Two patients had conjunctival manifestations in the form of conjunctivitis but conjunctival swab RT-PCR was negative in those patients. Among the RT-PCR positive patients, two (40%) were from mild, one (20%) was from moderate, and two (40%) were from severe category. No association could be established between conjunctival swab RT-PCR positivity and severity of the disease or associated comorbidity.Conclusion:Our study provides evidence that SARS-CoV-2 RNA could be detected in conjunctival secretions, and though the risk is relatively low, the eye may act as source of transmission. Extra caution should be taken by healthcare workers, and use of proper precautions like face shields and goggles should be encouraged.     

ACE2 and TMPRSS2 are expressed on the human ocular surface,suggesting susceptibility to SARS-CoV-2 infection

PurposeConjunctival signs and symptoms are observed in a subset of patients with COVID-19, and SARS-CoV-2 has been detected in tears, raising concerns regarding the eye both as a portal of entry and carrier of the virus. The purpose of this study was to determine whether ocular surface cells possess the key factors required for cellular susceptibility to SARS-CoV-2 entry/infection.MethodsWe analyzed human post-mortem eyes as well as surgical specimens for the expression of ACE2 (the receptor for SARS-CoV-2) and TMPRSS2, a cell surface-associated protease that facilitates viral entry following binding of the viral spike protein to ACE2.ResultsAcross all eye specimens, immunohistochemical analysis revealed expression of ACE2 in the conjunctiva, limbus, and cornea, with especially prominent staining in the superficial conjunctival and corneal epithelial surface. Surgical conjunctival specimens also showed expression of ACE2 in the conjunctival epithelium, especially prominent in the superficial epithelium, as well as weak or focal expression in the substantia propria. All eye and conjunctival specimens also expressed TMPRSS2. Finally, Western blot analysis of protein lysates from human corneal epithelium obtained during refractive surgery confirmed expression of ACE2 and TMPRSS2.ConclusionsTogether, these results suggest that ocular surface cells including conjunctiva are susceptible to infection by SARS-CoV-2, and could therefore serve as a portal of entry as well as a reservoir for person-to-person transmission of this virus. This highlights the importance of safety practices including face masks and ocular contact precautions in preventing the spread of COVID-19 disease.