Conjunctivitis can be the only presenting sign and symptom of COVID-19

The Review of Ophthalmic Symptoms in COVID-19

The COVID-19 pandemic caused by SARS-CoV-2 had a significant impact on the health of the global human population, affecting almost every human organ, including the organ of vision. Research focus on understanding the pathophysiology, identifying symptoms and complications of the disease. Eye-related pathologies are important foci of research due to the potential for direct impact of the virus. Ophthalmologists around the world are reporting various symptoms of eye infections and ocular pathologies associated with SARS-CoV-2. The review of ophthalmic symptoms was conducted to help physicians of various specialties recognize possible ophthalmic manifestations of this viral disease. A literature review was conducted from January 2020 to July 2023 in the PubMed, MEDLINE, Science Direct, Scopus, Scielo and Google Scholar databases. The review of the literature showed that conjunctivitis is the most common ophthalmic symptom observed during the course of COVID-19 and can occur at any stage of the disease. Changes in the eye may result from the direct effect of the virus, immune response, prothrombotic states, comorbidities, and medications used. Symptoms related to the organ of vision can be divided into: changes affecting the protective apparatus of the eye, the anterior eye segment, the posterior eye segment, neuro-ophthalmic, and orbital changes. Ocular symptoms may suggest COVID-19 infection or appear several weeks after recovery. Following COVID-19 vaccinations, a diverse range of ophthalmic symptoms was observed in various locations and at different times, mirroring the ocular symptoms experienced throughout the course of the COVID-19 illness. It is important for physicians of all specialties to be aware of possible potential connections between eye diseases and SARS-CoV-2, in order to effectively diagnose and treat patients.

Ocular manifestations of COVID-19: A systematic review of current evidence

Introduction

COVID-19 caused by SARS-CoV-2, commonly presents with symptoms such as fever and shortness of breath but can also affect other organs. There is growing evidence pointing to potential eye complications. In this article, we aim to systematically review the ocular manifestations of COVID-19.

Methods

We conducted a systematic review to explore the ocular manifestations of COVID-19. We searched online databases including PubMed, Embase, Scopus, and Web of Science up to September 4, 2023. After a two-stage screening process and applying inclusion/exclusion criteria, eligible articles were advanced to the data extraction phase. The PRISMA checklist and Newcastle-Ottawa Scale (NOS) were used for quality and bias risk assessments.

Results

We selected and extracted data from 42 articles. Most of the studies were cross-sectional (n = 33), with the highest number conducted in Turkey (n = 10). The most frequent ocular manifestation was conjunctivitis, reported in 24 articles, followed by photophobia, burning, chemosis, itching, and ocular pain. Most studies reported complete recovery from these manifestations; however, one study mentioned visual loss in two patients.

Conclusion

In general, ocular manifestations of COVID-19 appear to resolve either spontaneously or with supportive treatments. For more severe cases, both medical treatment and surgery have been employed, with the outcomes suggesting that complete recoveries are attainable.

Viral infections and pathogenesis of glaucoma: a comprehensive review

Glaucoma is a leading cause of irreversible blindness worldwide, caused by the gradual degeneration of retinal ganglion cells and their axons. While glaucoma is primarily considered a genetic and age-related disease, some inflammatory conditions, such as uveitis and viral-induced anterior segment inflammation, cause secondary or uveitic glaucoma. Viruses are predominant ocular pathogens and can impose both acute and chronic pathological insults to the human eye. Many viruses, including herpes simplex virus, varicella-zoster virus, cytomegalovirus, rubella virus, dengue virus, chikungunya virus, Ebola virus, and, more recently, Zika virus (ZIKV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), have been associated with sequela of either primary or secondary glaucoma. Epidemiological and clinical studies suggest the association between these viruses and subsequent glaucoma development. Despite this, the ocular manifestation and sequela of viral infections are not well understood. In fact, the association of viruses with glaucoma is considered relatively uncommon in part due to underreporting and/or lack of long-term follow-up studies. In recent years, literature on the pathological spectrum of emerging viral infections, such as ZIKV and SARS-CoV-2, has strengthened this proposition and renewed research activity in this area. Clinical studies from endemic regions as well as laboratory and preclinical investigations demonstrate a strong link between an infectious trigger and development of glaucomatous pathology. In this article, we review the current understanding of the field with a particular focus on viruses and their association with the pathogenesis of glaucoma.

Considerations of COVID-19 in Ophthalmology

Since its emergence in early 2020, the SARS-CoV-2 infection has had a significant impact on the entire eye care system. Ophthalmologists have been categorized as a high-risk group for contracting the virus due to the belief that the eye may be a site of inoculation and transmission of the SARS-CoV-2 infection. As a result, clinical ophthalmologists, optometrists, and eyecare professionals have had to familiarize themselves with the ocular manifestations of COVID-19, as well as its treatments and vaccines. The implementation of measures to prevent the transmission of the virus, such as restrictions, lockdowns, telemedicine, and artificial intelligence (AI), have led to substantial and potentially irreversible changes in routine clinical practice, education, and research. This has resulted in the emergence of a new mode of managing patients in a routine clinical setting. This brief review aims to provide an overview of various aspects of COVID-19 in ophthalmology, including the ocular manifestations related to the disease, the modes of transmission of SARS-CoV-2 infection, precautions taken in ophthalmic practice to prevent the spread of the virus, drugs, and vaccines used in the treatment of COVID-19, the impact of the pandemic on patients, clinicians, and the eye care system as a whole, and the future of ophthalmology conditioned by this global pandemic experience.

Macrophage Activation in Follicular Conjunctivitis during the COVID-19 Pandemic

Among the symptoms of SARS-CoV-2, follicular conjunctivitis has become relevant. The conjunctiva acts as an open lymph node, reacting to the viral antigen that binds the epithelial cells, forming follicles of B cells with activated T cells and NK cells on its surface, which, in turn, talk to monocyte-derived inflammatory infected macrophages. Here, the NLRP3 inflammasome is a major driver in releasing pro-inflammatory factors such as IL-6 and caspase-1, leading to follicular conjunctivitis and bulbar congestion, even as isolated signs in the 'asymptomatic' patient.

From energy storage to pathogen eradication: unveiling the antibacterial and antiviral capacities of flexible solid-state carbon cloth supercapacitors

With the emergence of deadly viral and bacterial infections, preventing the spread of microorganisms on surfaces has gained ever-increasing importance. This study investigates the potential of solid-state supercapacitors as antibacterial and antiviral devices. We developed a low-cost and flexible carbon cloth supercapacitor (CCSC) with highly efficient antibacterial and antiviral surface properties. The CCSC comprised two parallel layers of carbon cloth (CC) electrodes assembled in a symmetric, electrical double-layer supercapacitor structure that can be charged at low potentials between 1 to 2 V. The optimized CCSC exhibited a capacitance of 4.15 ± 0.3 mF cm-2 at a scan rate of 100 mV s-1, high-rate capability (83% retention of capacitance at 100 mV s-1 compared to its value at 5 mV s-1), and excellent electrochemical stability (97% retention of the initial capacitance after 1000 cycles). Moreover, the CCSC demonstrated outstanding flexibility and retained its full capacitance even when bent at high angles, making it suitable for wearable or flexible devices. Using its stored electrical charge, the charged CCSC disinfects bacteria effectively and neutralizes viruses upon surface contact with the positive and negative electrodes. The charged CCSC device yielded a 6-log CFU reduction of Escherichia coli bacterial inocula and a 5-log PFU reduction of HSV-1 herpes virus. Antibacterial and antiviral carbon cloth supercapacitors represent a promising platform technology for various applications, including electronic textiles and electronic skins, health monitoring or motion sensors, wound dressings, personal protective equipment (e.g., masks) and air filtration systems.

Long-term effects of SARS-CoV-2 infection on human brain and memory

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have caused several waves of outbreaks. From the ancestral strain to Omicron variant, SARS-CoV-2 has evolved with the high transmissibility and increased immune escape against vaccines. Because of the multiple basic amino acids in the S1-S2 junction of spike protein, the widespread distribution of angiotensin-converting enzyme 2 (ACE2) receptor in human body and the high transmissibility, SARS-CoV-2 can infect multiple organs and has led to over 0.7 billion infectious cases. Studies showed that SARS-CoV-2 infection can cause more than 10% patients with the Long-COVID syndrome, including pathological changes in brains. This review mainly provides the molecular foundations for understanding the mechanism of SARS-CoV-2 invading human brain and the molecular basis of SARS-CoV-2 infection interfering with human brain and memory, which are associated with the immune dysfunction, syncytia-induced cell death, the persistence of SARS-CoV-2 infection, microclots and biopsychosocial aspects. We also discuss the strategies for reducing the Long-COVID syndrome. Further studies and analysis of shared researches will allow for further clarity regarding the long-term health consequences.

[The problem of long/post-COVID in expert assessments]

Assessing long/post-COVID syndrome (PCS) following an infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a multidisciplinary challenge due to the diverse and complex symptoms. Besides discipline-specific evaluation of infection-related organ damage, the main issue is expert objectivity and causality assessment regarding subjective symptoms. The consequences of long/PCS raise questions of insurance rights in all fields of law. In cases of persistent impairment of performance, determining reduction in earning capacity is crucial for those affected. Recognition as an occupational disease (BK no. 3101) is vital for employees in healthcare and welfare sectors, along with occupational accident recognition and assessing the illness's consequences, including the reduction in earning capacity (MdE) in other sectors or work areas. Therefore, expert assessments of illness consequences and differentiation from previous illnesses or damage disposition are necessary in all areas of law, individually based on corresponding organ manifestations in medical fields and interdisciplinarily for complex late sequelae, for instance, by internists with appropriate qualifications for pulmonary or cardiac manifestations and neurologists, psychiatrists, and neuropsychologists for neurological and psychiatric manifestations, etc.

Mortality patterns among COVID‐19 patients in two Saudi hospitals: Demographics, etiology, and treatment

Background

Saudi Arabia (SA) reported its first case of COVID‐19 on 2 March 2020. Mortality varied nationwide; by April 14, 2020, Medina had 16% of SA's total COVID‐19 cases and 40% of all COVID‐19 deaths. A team of epidemiologists investigated to identify factors impacting survival.

Methods

We reviewed medical records from two hospitals: Hospital A in Medina and Hospital B in Dammam. All patients with a registered COVID‐related death between March and May 1, 2020, were included. We collected data on demographics, chronic health conditions, clinical presentation, and treatment. We analyzed data using SPSS.

Results

We identified 76 cases: 38 cases from each hospital. More fatalities were among non‐Saudis at Hospital A (89%) versus Hospital B (82%, p < 0.001). Hypertension prevalence was higher among cases at Hospital B (42%) versus Hospital A (21%) (p < 0.05). We found statistically significant differences (p < 0.05) in symptoms at initial presentation among cases at Hospital B versus Hospital A, including body temperature (38°C vs. 37°C), heart rate (104 bpm vs. 89 bpm), and regular breathing rhythms (61% vs. 55%). Fewer cases (50%) at Hospital A received heparin versus Hospital B (97%, p‐value < 0.001).

Conclusion

Patients who died typically presented with more severe illnesses and were more likely to have underlying health conditions. Migrant workers may be at increased risk due to poorer baseline health and reluctance to seek care. This highlights the importance of cross‐cultural outreach to prevent deaths. Health education efforts should be multilingual and accommodate all literacy levels.

Ocular symptoms in COVID-19 infection: a survey study

BACKGROUND

Coronavirus disease 2019 (COVID-19) systemic symptoms and sequelae have been studied extensively, but less is known about the characterization, duration, and long-term sequelae of ocular symptoms associated with COVID-19 infection. The purpose of this study was to analyze the frequency, spectrum, and duration of ocular symptoms in participants with COVID-19 infection treated in inpatient and outpatient settings.

METHODS

A retrospective electronic survey was distributed to NIH employees and the public who reported testing positive for SARS-CoV-2. The anonymous survey collected information on demographics, past ocular history, systemic COVID-19 symptoms, and ocular symptoms.

RESULTS

A total of 229 (21.9% male and 78.1% female, mean age 42.5 ± 13.9) survey responses were included. Ocular symptoms were reported by 165 participants with a mean of 2.31 ± 2.42 symptoms. The most commonly reported ocular symptoms were light sensitivity (31.0%), itchy eyes (24.9%), tearing (24.9%), eye redness (24.5%), and eye pain (24.5%). Participants with ocular symptoms had a higher number of systemic symptoms compared to participants without ocular symptoms (mean 9.17 ± 4.19 vs 6.22 ± 3.63; OR: 1.21; 95% CI: 1.11 - 1.32; p < 0.001). Ocular symptoms were more common in those who reported a past ocular history compared to those who did not (81.8% vs 67.1%; OR: 2.17; 95% CI: 1.08 - 4.37; p = 0.03). Additionally, the onset of ocular symptoms occurred most frequently at the same time as systemic symptoms (47.5%), and 21.8% reported symptoms lasting ≥ 14 days.

CONCLUSIONS

Ocular surface-related symptoms are the most frequent ocular manifestations, and systemic disease severity is associated with the presence of ocular symptoms. Additionally, our results show that ocular symptoms can persist post-COVID-19 infection. Further work is needed to better understand ocular symptoms in COVID-19 and long-term sequelae.

Eye damage in COVID-19. Part 1: Involvement of the eye in SARS-CoV-2 virus transmission and anterior segment complications

In COVID-19, eye damage may develop at any stage of the disease. Viral ribonucleic acid has been found in ocular tissues, but the role of the eye as a route of infection is yet to be substantiated. Ophthalmic manifestations may be a typical feature of COVID-19 infection or they may develop several weeks after recovery. Ophthalmologists should be aware of possible relationships of an ophthalmic pathology with SARS-CoV-2 in order to obtain targeted case history, detect the specific signs, prescribe the necessary tests and thereby reduce the spread of the infection. These relationships are also important for early diagnosis and treatment of complications that threaten the patients’ life and vision. The first part of the review focuses on the possible involvement of the eye in SARS-CoV-2 infection and the spread of infection. Clinical manifestations of the anterior segment damage are considered.

[German S1 Guideline Long-/Post-COVID]

The German Society of Pneumology initiated 2021 the AWMF S1 guideline Long COVID/Post-COVID. In a broad interdisciplinary approach, this S1 guideline was designed based on the current state of knowledge.The clinical recommendations describe current Long COVID/Post-COVID symptoms, diagnostic approaches, and therapies.In addition to the general and consensus introduction, a subject-specific approach was taken to summarize the current state of knowledge.The guideline has an explicit practical claim and will be developed and adapted by the author team based on the current increase in knowledge.

Executive summary: Japanese guidelines for allergic conjunctival diseases 2021

Allergic conjunctival disease (ACD) is an inflammatory disease of the conjunctiva that is mainly caused by type I hypersensitivity response to allergens and accompanied by subjective symptoms and other findings induced by antigens. ACD is classified as allergic conjunctivitis, atopic keratoconjunctivitis, vernal keratoconjunctivitis, and giant papillary conjunctivitis. This article summarizes the third edition of the Japanese guidelines for allergic conjunctival diseases published in 2021 and outlines the diagnosis, pathogenesis, and treatment of ACD. Since the introduction of immunosuppressive eye drops, the treatment strategies for severe ACDs have significantly changed. To clarify the recommended standard treatment protocols for ACD, the advantages and disadvantages of these treatments were assessed using clinical questions, with a focus on the use of steroids and immunosuppressive drugs. This knowledge will assist healthcare providers and patients in taking an active role in medical decision making.

Evaluation of Face Shields, Goggles, and Safety Glasses as a Virus Transmission Control Measure to Protect the Wearer Against Cough Droplets

Face shields (also referred to as visors), goggles and safety glasses have been worn during the COVID-19 pandemic as one measure to control transmission of the virus. However, their effectiveness in controlling facial exposure to cough droplets is not well established and standard tests for evaluating eye protection for this application are limited. A method was developed to evaluate face shields, goggles, and safety glasses as a control measure to protect the wearer against cough droplets. The method uses a semi-quantitative assessment of facial droplet deposition. A cough simulator was developed to generate droplets comparable to those from a human cough. The droplets consisted of a UV fluorescent marker (fluorescein) in water. Fourteen face shields, four pairs of goggles and one pair of safety glasses were evaluated by mounting them on two different sizes of breathing manikin head and challenging them with the simulated cough. The manikin head was positioned in seven orientations relative to the cough simulator to represent various potential occupational exposure scenarios, for example, a nurse standing over a patient. Droplet deposition in the eyes, nose and mouth regions were visualised following three 'coughs'. Face shields, goggles, and safety glasses reduced, but did not eliminate exposure to the wearer from droplets such as those produced by a human cough. The level of protection differed based on the design of the personal protective equipment and the relative orientation of the wearer to the cough. For example, face shields, and goggles offered the greatest protection when a cough challenge was face on or from above and the least protection when a cough challenge was from below. Face shields were also evaluated as source control to protect others from the wearer. Results suggested that if a coughing person wears a face shield, it can provide some protection from cough droplets to those standing directly in front of the wearer.

Conjunctival epithelial cells resist productive SARS-CoV-2 infection

Conjunctival epithelial cells, which express viral-entry receptors angiotensin-converting enzyme 2 (ACE2) and transmembrane protease serine type 2 (TMPRSS2), constitute the largest exposed epithelium of the ocular surface tissue and may represent a relevant viral-entry route. To address this question, we generated an organotypic air-liquid-interface model of conjunctival epithelium, composed of basal, suprabasal, and superficial epithelial cells, and fibroblasts, which could be maintained successfully up to day 75 of differentiation. Using single-cell RNA sequencing (RNA-seq), with complementary imaging and virological assays, we observed that while all conjunctival cell types were permissive to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome expression, a productive infection did not ensue. The early innate immune response to SARS-CoV-2 infection in conjunctival cells was characterised by a robust autocrine and paracrine NF-κB activity, without activation of antiviral interferon signalling. Collectively, these data enrich our understanding of SARS-CoV-2 infection at the human ocular surface, with potential implications for the design of preventive strategies and conjunctival transplantation.

How Does SARS-CoV-2 Affect Our Eyes-What Have We Learnt So Far about the Ophthalmic Manifestations of COVID-19?

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection has become a worldwide threat resulting in a pandemic in 2020. SARS-CoV-2 infection manifests itself as coronavirus disease 2019 (COVID-19) that is evidenced in a vast number of either specific or nonspecific symptoms. Except for typical (but nonspecific) symptoms such as fever, dry cough, or muscle weakness, the infected patients might also present atypical symptoms including neurological, dermatological, or ophthalmic manifestations. This paper summarizes the current state of knowledge regarding the onset, progression, and types of ophthalmic symptoms induced by SARS-CoV-2 infection recognized amongst the infected patients.

COVID-19-related Conjunctivitis Review: Clinical Features and Management

PURPOSE

The ongoing coronavirus disease-2019 (COVID-19) pandemic has greatly impacted theworld. In this review article, we discuss the conjunctival and nasolacrimal mucosa as a potential route for the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) transmission, its ocular manifestations, and management.

METHODS

Literature review was conducted in the PubMed, Google Scholar and EMBASE databases using keywords such as "coronavirus", COVID-19", "SARS-CoV-2", "conjunctivitis", "ocular surface", "eye" and "ophthalmology".

RESULTS

The ocular surface may serve as an entry point and reservoir for the virus. Frequency of hand-eye contact was an independent risk factor for COVID-19-related conjunctivitis. Therefore, appropriate protective eyewear or face shields are recommended, especially for health-care workers. Bilateral conjunctival sampling within 9 days of symptom onset provides a higher positive yield rate. Pooled analysis shows an incidence of 11.4% (95%CI = 6.4-17.2%) of ocular manifestations in patients with SARS-CoV-2 infection, including hospitalized and non-hospitalized patients.

CONCLUSION

Conjunctivitis was the most common ocular manifestation, of which ocular redness or congestion, ocular pain, and follicular conjunctivitis were the most common presentation.COVID-19-related conjunctivitis has a self-limiting disease course, and treatment should be mainly supportive.

Tracing the SARS-CoV-2 infection on the ocular surface: Overview and preliminary corneoscleral transcriptome sequencing

COVID-19's impact on the ocular surface has already been recognized, however the molecular mechanisms induced by the infection on the ocular surface are still unclear. The aim of this paper is to provide a first overview of the transcriptional perturbations caused by SARS-CoV-2 on the ocular surface by analyzing gene expression profile of corneoscleral ring samples from post-mortem SARS-CoV-2 positive donors (PD). The presence of SARS-CoV-2 on the ocular surface, in tears and corneal tissues has rarely been detected in infected individuals in both the presence and the absence of ocular manifestations. In this preliminary study, 6 human corneoscleral tissues of 3 PD and two tissues from a negative donor (CTRL) were obtained at the local eye bank. The presence of genomic and sub-genomic SARS-CoV-2 RNAs was assessed by qRT-PCR, while transcriptome analysis (RNA-sequencing) was performed by Illumina. Principal Component Analysis (PCA), search for differentially expressed genes (DEGs) and Gene Ontology (GO)-enrichment analysis were performed. Three samples from PD were found positive for SARS-CoV-2 genomic RNA, although the absence of sub-genomic RNAs indicated an inactive virus. PCA analysis grouped 3 different clusters, one including CTRL, and the other two including, respectively, PD with undetected SARS-CoV-2 (PD-SARS-neg) and PD with detected SARS-CoV-2 (PD-SARS-pos). The DEGs in common with the 2 PD clusters included several genes associable to the interferon pathway, such as ADAMTS4, RSAD2, MMP1, IL6, ISG15 and proinflammatory cytokines. Among the down-regulated genes we found AQP5. GO analysis revealed 77 GO terms over-represented in PD-SARS-neg vs. CTRL, and 17 GO terms in PD-SARS-pos vs. CTRL. The presence of SARS-CoV-2 RNA and RNA-sequencing reads in ocular surface tissues supports the possibility that the eye acts as an entry route. The modulation of early responsive genes, together with several ISGs suggests a potential protective responsiveness of the ocular tissues to SARS-CoV-2.

COVID-19 pandemic: multilevel dental technical guidelines based on new scientific evidence

The COVID-19 pandemic imposed restrictive measures on dentistry in different regions of the world, ranging from stoppage of care to only permission for urgent and emergency dental services. Thus, new biosafety guidelines for resuming activities, whether in single dental offices, large clinics or dental education activities, are urgently required. In this sense, herein, guidelines that incorporate common points of the main protocols found in the literature for the resumption of dental activities at their different levels, whether in the scope of care or education, are presented. Furthermore, we present the incorporation of measures that allow an increase in the level of biosafety, such as the control of the dental team, the inclusion in the history of conjunctivitis as a possible alert for COVID-19, and the use of the pulse oximeter to assess the risk of silent hypoxemia, which may indicate a complication of COVID-19. In addition, new perspectives for directing research and innovation for biosafety in dentistry are discussed.

Coronavirus Disease 2019, Eye Pain, Headache, and Beyond

BACKGROUND

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2), which causes Coronavirus Disease 2019 (COVID-19), emerged in December 2019 and became a devastating pandemic. Although its respiratory effects can be deadly and debilitating, it can lead to other systemic disorders, such as those causing eye pain and headache. This literature review aims to describe presentations of eye pain and headache in relation to COVID-19, with an emphasis on how these disorders help us to understand the pathophysiology of COVID-19.

EVIDENCE ACQUISITION

Literature was mined from the PubMed database using the key terms: "eye pain," "conjunctivitis," "episcleritis," "optic neuritis," "migraine," and "headache" in conjunction with "COVID-19" and "SARS-CoV-2." With the exception of general background pathology, articles that predated 2006 were excluded. Case reports, literature reviews, and meta-analyses were all included. Where SARS-CoV-2 research was deficient, pathology of other known viruses was considered. Reports of ocular manifestations of vision loss in the absence of eye pain were excluded. The primary search was conducted in June 2021.

RESULTS

The literature search led to a focused review of COVID-19 associated with conjunctivitis, episcleritis, scleritis, optic neuritis, and myelin oligodendrocyte glycoprotein-associated optic neuritis. Four distinct COVID-19-related headache phenotypes were identified and discussed.

CONCLUSIONS

Eye pain in the setting of COVID-19 presents as conjunctivitis, episcleritis, scleritis, or optic neuritis. These presentations add to a more complete picture of SARS-CoV-2 viral transmission and mechanism of host infection. Furthermore, eye pain during COVID-19 may provide evidence of hypersensitivity-type reactions, neurovirulence, and incitement of either novel or subclinical autoimmune processes. In addition, investigation of headaches associated with COVID-19 demonstrated 4 distinct phenotypes that follow third edition of the International Classification of Headache Disorders categories: headaches associated with personal protective equipment, migraine, tension-type headaches, and COVID-19-specific headache. Early identification of headache class could assist in predicting the clinical course of disease. Finally, investigation into the COVID-19-associated headache phenotype of those with a history of migraine may have broader implications, adding to a more general understanding of migraine pathology.

Hydrodynamic Interaction Between Tear Film and Air Puff From Noncontact Tonometry

Purpose

The purpose of this study was to investigate the mechanism of potential droplet formation in response to air puff deformation with two noncontact tonometers (NCTs).

Methods

Twenty healthy volunteers were examined using two NCTs, Ocular Response Analyzer and Corvis ST, and two contact tonometers, iCare and Tono-Pen. High-speed videos of the tear film response were captured with at spatial resolution of 20 microns/pixel at 2400 fps. Droplet size, droplet velocity, distance between air puff impact location, and the tear meniscus-lid margin were characterized.

Results

One subject was excluded due to technical issues. Droplets were detected only in tests with instilled eye drop. Videos showed the tear film rolls away from the apex while remaining adherent to the ocular surface due to the tendency of the fluid to remain attached to a solid surface explained by the Coanda effect. Twelve out of 38 videos with an eye drop administration showed droplet formation. Only one resulted in droplets with predominantly forward motion, which had the shortest distance between air puff impact location and lower meniscus. This distance on average was 5.9 ± 1.1 mm. The average droplet size was 500 ± 200 µm.

Conclusions

Results indicate no droplet formation under typical clinical setting. Hence, standard clinical use of NCT tests is not expected to cause droplets. NCT testing with eye drop administration showed droplet formation at the inferior eyelid boundary, which acts as a barrier and interrupts tear flow.

Translational Relevance

Study of tear film interaction with NCT air puff shows that these tonometers are not expected to cause droplet formation in standard use and that if external drops are required, both eyelids should be held if patients need assistance to maintain open eyes to avoid droplets with predominantly forward motion.

The Eye of the Storm: COVID-19 Vaccination and the Eye

The COVID-19 pandemic has galvanized the global response towards the development of new vaccines based on novel technologies at an unprecedented pace. Since the widespread implementation of vaccination campaigns, case reports on vaccines' systemic side effects, including ocular manifestations, have emerged. Since administered vaccines are generally not able to cause the disease in the recipient, or induce an immune response against the pathogen, we hypothesize that the development of ocular phenomena post-COVID-19 vaccination may occur via an immune response elicited by the vaccine. Of many, the most common ocular adverse events include facial nerve palsy, central venous sinus thrombosis and acute anterior uveitis. These COVID-19 vaccine-induced ocular (CVIO) adverse events could resemble the ocular findings in some of the COVID-19 patients. This review will provide a comprehensive overview of published ocular side effects potentially associated with COVID-19 vaccination and serve as a springboard for further research into CVIO adverse events.

Prevalence of SARS-CoV-2 in Conjunctival Swab Samples Among Patients Presenting with Conjunctivitis During the COVID-19 Pandemic

Purpose

To investigate the prevalence of SARS-CoV-2-associated conjunctivitis among patients presenting with conjunctivitis to ophthalmology clinics in the absence of respiratory symptoms suggesting COVID-19 during the first year of the pandemic.

Patients and Methods

This prospective, observational, cross-sectional study enrolled patients aged 18 years and older who presented with acute conjunctivitis between May 2020 and May 2021. After reviewing demographics, ocular and systemic symptoms, a slit lamp examination was performed. Five samples were collected (conjunctival swab from each eye, nasal swab from each nostril, and a nasopharyngeal swab) in separate tubes for a reverse transcription-polymerase chain reaction test for SARS-CoV-2. Patients were called at 1 and 2 weeks to follow up on their ocular and systemic symptoms and collect information about conjunctival adenovirus test results and COVID-19 test results if performed outside of the study.

Results

A total of 36 patients were enrolled. The most common ocular symptom was redness (35/36, 97%), and 14 patients (39%) had symptoms in both eyes at the time of the presentation. SARS-CoV-2 RNA was not detected in any samples collected during the study visit (95% confidence interval [CI] from 0 to 0.08). None of the study participants were diagnosed with COVID-19 following conjunctivitis during the 2-week follow-up period. We found that 25 patients had a conjunctival adenovirus test done on the day of their study visit, 9 of which reported positive results.

Conclusion

Our data suggest that it may not be valuable to obtain routine testing of SARS-CoV-2 in patients presenting with conjunctivitis in the absence of COVID-19.

COVID-19 and the Human Eye: Conjunctivitis, a Lone COVID-19 Finding - A Case-Control Study

OBJECTIVES

COVID-19 has varied clinical manifestations, from asymptomatic to severe cases, and conjunctivitis is one of them, but sometimes a lone initial symptom is found to be present. The aim of this study was to identify the prevalence of conjunctivitis as the first symptom in COVID-19 patients in a primary healthcare unit.

METHODOLOGY

A retrospective study was conducted, analyzing the presenting complains/symptoms and results of COVID-19-confirmatory tests.

RESULTS

Out of the 672 cases that were sent for RT-PCR testing, only 121 (18%) were found to be positive. Among these, 2.67% patients had both conjunctivitis and COVID-19, 77.77% patients had unilateral eye affected, while 22.22% had bilateral conjunctivitis of varying degrees. Fifteen patients diagnosed to have both acute conjunctivitis and COVID-19 presented other symptoms associated with COVID-19 infection. Three patients had only acute conjunctivitis during their entire course of COVID-19.

CONCLUSIONS

Conjunctivitis is a symptom of COVID-19 and may be the first sign of the infection, until the onset of the classical manifestations; such patients may continue to be a viral reservoir. Physicians should not miss unilateral conjunctivitis as it can be the only presenting complaint of COVID-19 during the initial phase, which might worsen if undetected and can aid in the spread of the contagion.

COVID-19: Update on Its Ocular Involvements, and Complications From Its Treatments and Vaccinations

ABSTRACT

The coronavirus disease 2019 (COVID-19) came under the attention of the international medical community when China first notified the World Health Organization of a pneumonia outbreak of then-unknown etiology in Wuhan in December 2019. Since then, COVID-19 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has appalled the world by spreading at a pandemic speed. Although ophthalmologists do not directly engage in the clinical care of COVID-19 patients, the ophthalmology community has become aware of the close ties between its practice and the pandemic. Not only are ophthalmologists at heightened risk of SARS-CoV-2 exposure due to their physical proximity with patients in routine ophthalmic examinations, but SARS-CoV-2 possesses ocular tropism resulting in ocular complications beyond the respiratory tract after viral exposure. Furthermore, patients could potentially suffer from adverse ocular effects in the therapeutic process. This review summarized the latest literature to cover the ophthalmic manifestations, effects of treatments, and vaccinations on the eye to aid the frontline clinicians in providing effective ophthalmic care to COVID-19 patients as the pandemic continues to evolve.

Conjunctivitis as a sign of persistent SARS-COV-2 infection? An observational study and report of late symptoms

PURPOSE

To investigate if symptomatic conjunctivitis during the recovery phase of the disease could be associated to a persistent presence of SARS-CoV-2 in the upper respiratory tract. Secondary end points were to analyze the presence of SARS-CoV-2 in the conjunctiva of ocular symptomatic patients and to record the presence of ocular disturbances at this point of the disease.

METHODS

An observational study including consecutive COVID19 patients treated at Humanitas Clinical and Research Hospital who were attending for nasopharyngeal swab to confirm the resolution of SARS-CoV-2 infection and end of isolation. We examined 129 consecutive patients from May to June 2020. The primary end point was to determine if symptomatic conjunctivitis at this point of the disease could be associated to a persistent presence of SARS-CoV-2 in the upper respiratory tract. Secondary end points were to analyze the presence of SARS-CoV-2 in the conjunctiva of ocular symptomatic patients and to record the presence of ocular disturbances at this point of the disease.

RESULTS

One hundred twenty eight patients were included, 9.38% had conjunctivitis, none resulted positive to conjunctival PCR swab test, while two of them had positive nasopharyngeal result. Mean time elapsed since the first COVID-19 positive swab to the time of examination was 6 weeks (  ± 3). The only significant association was the presence of conjunctivitis with older age (65.3  ±  12.7 vs 56.7  +  13.5. p  =  0.046). Nasopharyngeal swab resulted positive in 22 patients (17.19%). While 88 patients (68.2%) did not have any ocular complain during their COVID19 disease. The 40 patients (31.8%) reporting ocular disturbances complained about: redness (25.43%), tearing (19.53%), burning (18.35%), foreign body sensation (17.18%), itching (15.62%), and discharge (12.5%).

CONCLUSION

This study showed that late conjunctivitis cannot be considered as a marker of persistent infection when patients are sent to confirm the resolution of SARS-CoV-2 infection.

COVID-19 case presented initially with keratoconjunctivitis: A case report

Introduction

Ocular complaints are considered non-classical presentations for COVID-19 infection; the initial diagnosis of keratoconjunctivitis is even rarer. Indeed, this puts treating clinicians in danger of getting infected, especially when patients present without the classic respiratory symptoms.

Case

Here we report a case of COVID-19 that was initially presented with keratoconjunctivitis with the appearance of respiratory symptoms four days later. The case showed improvement within four days of successful treatment for both covid pneumonia and ocular disease.

Discussion

Countable cases reported initial ocular symptoms to co-occur with systemic symptoms or even before. Only two cases reported the diagnosis of keratoconjunctivitis in COVID-19. The two cases differ in the proposed mechanism of developing such disorder. One by direct invasion of the virus, the other one by cytokines-induced epithelial injury. Our case did not show positivity for SARS-CoV 2 in the eye secretion, which aligns with the later proposed mechanism of pathology.

Conclusion

It is crucial to report such cases to increase the awareness of atypical presentation for COVID-19 infection. This is too important for two reasons: first, to diagnose the disease itself, and second, to take infection control precautions when treating such cases, with unexpected initial presentation.

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Atypical presentation for COVID-19 infection.

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COVID-19 may initially present with ocular complains.

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Countable cases reported initial ocular symptoms to co-occur with systemic symptoms.

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Infectivity either by direct invasion or cytokines-induced epithelial injury.

Retinal microvascular and perfusional disruption in paediatric COVID-19: A case-control optical coherence tomography angiography study

Purpose

To investigate the short-term effect of coronavirus 2019 (COVID-19) on the retinal capillary network and choroid in children.

Materials and methods

This prospective, cross-sectional, case-control study included 19 recovered COVID-19 pediatric patients and 20 healthy children. Macular thickness, choroidal thickness, vessel density (VD), perfusion density (PD), and foveal avascular zone (FAZ) values were obtained. Central vessel and perfusion densities were measured at the central 6-mm area, and the values were compared among three subgroups according to location.

Results

The mean ages of patients and controls were 12. 42 ± 3.3 years and 13.35 ± 1.2 years, respectively. Significant differences were observed between the two groups in terms of inner, outer, and full VD, as well as inner and full PD. No significant differences in center VD and PD were observed between groups. Although it was not evident in analysis of choroidal values, inflammatory sites were thickened. FAZ area significantly differed between groups (p < 0.05).

Conclusions

Retinal microvascularity was impaired in the acute phase of disease in recovered COVID-19 patients aged 10–15 years. However, the microvascularity impairment was subclinical. The choroid was thickened because of inflammation during the acute phase of disease. pediatric COVID-19 patients should undergo follow up via optical coherence tomography angiography to detect subclinical and asymptomatic retinal changes. Long-term follow-up studies are needed to validate these findings.

In-Depth Investigation of Conjunctival Swabs and Tear Fluid of Symptomatic COVID-19 Patients, an Observational Cohort Study

Purpose

The putative presence of SARS-CoV-2 in ocular specimen puts healthcare workers at risk. We thoroughly examined conjunctival swabs and tear fluid in a large cohort of COVID-19 patients.

Methods

A total of 243 symptomatic laboratory-confirmed COVID-19 patients were included in this observational multicenter study. Conjunctival swabs were analyzed by reverse transcription polymerase chain reaction for detection of SARS-CoV-2 RNA. Next-generation sequencing and phylogenetic analysis were performed to identify viral strains and to determine tissue tropism. Schirmer tear samples from 43 hospitalized COVID-19 patients and 25 healthy controls were analyzed by multiplex cytokine immunoassays.

Results

Viral SARS-CoV-2 RNA was detected in conjunctival swabs from 17 (7.0%) of 243 COVID-19 patients. Conjunctival samples were positive for viral SARS-CoV-2 RNA as long as 12 days after disease onset. Cycle threshold (Ct) values for conjunctival swabs (mean 34.5 ± 5.1) were significantly higher than nasopharyngeal swabs (mean 16.7 ± 3.6). No correlation between Ct values of conjunctival and nasopharyngeal swabs was observed. The majority of positive conjunctival samples were detected only once and primarily during the first visit. Next-generation sequencing analysis revealed that the virus strain found in the conjunctiva was most often identical to the one found in the nasopharynx. Tear cytokine levels IL-1β and IL-6 were elevated in COVID-19 patients compared to healthy controls.

Conclusions

Conjunctival samples that were positive for SARS-CoV-2 RNA contained the same viral strain as the nasopharynx.

Translational Relevance

The presence of SARS-CoV-2 viral RNA and elevated cytokines in tear fluid confirm the involvement of the ocular surface in COVID-19 disease.

Pattern of ocular manifestations and the prevalence of severe acute respiratory syndrome coronavirus-2 in tears of hospitalized coronavirus disease 2019 patients

PURPOSE:

Severe acute respiratory syndrome coronavirus2 (SARSCoV2) can affect eyes in various forms. Furthermore, ocular surface can act as potential port of entry and ocular secretions as possible route of transmission of SARSCoV2. The aims of the study are to identify ocular manifestation in confirmed coronavirus disease 2019 (COVID19) patients and to evaluate conjunctival secretions as the possible route of transmission of this disease.

MATERIALS AND METHODS:

A prospective, populationbased, observational study was done. Ocular symptoms and signs of every hospitalized patient with SARSCoV2 infection between September 15, 2020, and November 15, 2020, were recorded. Tear samples of the first 60 participants (30 each of patients with severe and moderate illness, can be removed) with ocular manifestations were selected for real-time polymerase chain reaction (RTPCR). Data were analyzed using the Statistical Package for the Social Science Software (SPSS) program, version 23. When comparing mean values, ttest was used otherwise Chisquare test.

RESULTS:

Out of 804 admitted patients during study period, 309 (38.4%) patients were identified with ocular manifestations, out of which 78% (241) had conjunctival hyperemia, 65.6% (203) had follicular reaction in palpebral conjunctiva, 58% (180) had chemosis, and 58% (99) had discharge and 18.4% (57) complained of burning in their eyes. Mean duration from systemic manifestation to onset of ocular symptoms was 4.52 ± 1.47 days while 8 patients (1%) had conjunctivitis as the presenting symptom. SARSCoV2 was detected in 18.3% patients (11 out of 60) using RTPCR.

CONCLUSION:

The presence of SARSCoV2 in ocular secretions of patients with ocular manifestations suggests that COVID19infected patients with ocular manifestations should wear protective glasses to prevent secretions contamination to healthy persons.

Key ingredients and recycling strategy of personal protective equipment (PPE): Towards sustainable solution for the COVID-19 like pandemics

The COVID-19 pandemic has intensified the complications of plastic trash management and disposal. The current situation of living in fear of transmission of the COVID-19 virus has further transformed our behavioural models, such as regularly using personal protective equipment (PPE) kits and single-use applications for day to day needs etc. It has been estimated that with the passage of the coronavirus epidemic every month, there is expected use of 200 billion pieces of single-use facemasks and gloves. PPE are well established now as life-saving items for medicinal specialists to stay safe through the COVID-19 pandemic. Different processes such as glycolysis, hydrogenation, aminolysis, hydrolysis, pyrolysis, and gasification are now working on finding advanced technologies to transfer waste PPE into value-added products. Here, in this article, we have discussed the recycling strategies of PPE, important components (such as medical gloves, gowns, masks & respirators and other face and eye protection) and the raw materials used in PPE kits. Further, the value addition methods to recycling the PPE kits, chemical & apparatus used in recycling and recycling components into value-added products. Finally, the biorenewable materials in PPE for textiles components have been discussed along with concluded remarks.

Symptoms and signs of conjunctivitis as predictors of disease course in COVID-19 syndrome

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can induce conjunctivitis signs and symptoms. However, limited information is available on their impact on COVID-19 disease phenotype. Quantification of ocular signs/symptoms can provide a rapid, non-invasive proxy for predicting clinical phenotype. Moreover, the existence and entity of conjunctival viral shedding is still debated. This has relevant implications to manage disease spread. The purpose of this study was to investigate conjunctivitis signs and symptoms and their correlation with clinical parameters, conjunctival viral shedding in patients with COVID-19.

METHODS

Fifty-three patients hospitalized between February 25th and September 16th, 2020 at the San Raffaele Hospital, in Milan, Lombardy, Italy with a confirmed diagnosis of SARS-CoV-2 were evaluated. Presence of interstitial pneumonia was confirmed with computed tomography scan imaging. Ocular signs and symptoms, anosmia/ageusia, clinical/laboratory parameters, and reverse transcriptase-polymerase chain reaction (RT-PCR) from nasopharyngeal and conjunctival swabs for COVID-19 virus were analyzed.

RESULTS

Forty-six out of 53 patients showed a positive nasopharyngeal swab for SARS-CoV-2 infection at the time of conjunctival evaluation. All the conjunctival swabs were negative. Conjunctivitis symptoms were present in 37% of patients. Physician-assessed ocular signs were detected in 28% of patients. Patients with ocular symptoms or signs tended to be older: 76.8 years (62.4-83.3) vs 57.2 years (48.1-74.0), p = 0.062 and had a longer hospitalization: 38 days (18-49) vs. 14 days (11-21), p = 0.005. Plasma levels of Interleukin-6 were higher in patients with signs or symptoms in comparison with those without them: 43.5 pg/ml (19.7-49.4) vs. 8 pg/ml (3.6-20.7), p = 0.02. Red cell distribution width was also significantly higher: 15 (14.3-16.7) vs 13.2 (12.4-14.4), p = 0.001.

CONCLUSIONS

We found that over a third of the patients had ocular signs or symptoms. These had higher prevalence in patients with a more severe infection. No viral shedding was detected in the conjunctiva. Our results suggest that prompt detection of conjunctivitis signs/symptoms can serve as a helpful proxy to predict COVID-19 clinical phenotype.

Conjunctivitis as the only sign and symptom of COVID-19: A case report and review of literature

Similar to several viruses, coronaviruses can affect the eye and cause conjunctivitis. In addition to ocular involvement, it causes systemic manifestations, mainly respiratory symptoms. However, conjunctivitis as the only sign and symptom of coronavirus disease 2019 (COVID-19) is a rare presentation. We present a case of a 20-year-old male patient who presented with conjunctivitis for 3 days and diagnosed on the same day with COVID-19 without other manifestations. Conjunctivitis affected both eyes and resolved over 2 weeks with artificial tears only and without any ocular complications.

Conjunctivitis can be the only sign and symptom of COVID-19 in some patients. Therefore, healthcare providers, particularly ophthalmologists, should take precautions when dealing with patients presenting with conjunctivitis amid the COVID-19 pandemic.

SARS-CoV-2 and the Eyes: A Review of the Literature on Transmission, Detection, and Ocular Manifestations

During the coronavirus disease 2019 (COVID-19) pandemic, numerous reports of ocular anomalies occurring in patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have emerged. The most frequently reported pathology is conjunctivitis, which may be the first or only clinical manifestation of the disease. Involvement of SARS-CoV-2 in development of alterations in other ocular structures was suggested, including the cornea, the retina, and blood vessels. Possible mechanisms include direct activity of the viral agent, as well as systemic inflammatory response with accompanying thromboembolic complications. Genetic material of SARS-CoV-2 was detected in ocular secretions of infected individuals, including asymptomatic patients. Moreover, angiotensin-converting enzyme 2 (ACE2), a receptor protein used by the virus to enter the cell, has been found on the surface of various structures of the eye, which indicates a risk of transmission through ocular tissues. Therefore, it is crucial to use eye protection by medical professionals having contact with potentially infected patients. This paper is a review of the literature regarding ocular manifestations of SARS-CoV-2 infection and a summary of the current state of knowledge about possibility of transmission from an ophthalmology point of view. For data collection, a thorough PubMed search was performed, using the key words: "COVID ocular", "COVID eye", "SARS-CoV-2 ocular", and "SARS-CoV-2 eye". Conclusions: SARS-CoV-2 infection may manifest itself in various ocular conditions. Eye protection should not be neglected, as recent studies suggest the eye as a potential route of transmission. Further search for adequate safety measures in ophthalmology practice is required.

Ophthalmia neonatorum as the presenting sign of SARS-CoV-2

The most common ocular manifestation of SARS-CoV-2 in adults and children is acute conjunctivitis. We report the case of a 4-day-old infant who presented with acute-onset mucopurulent discharge of the left eye as well as subconjunctival hemorrhage and palpebral injection, without corneal findings. A diagnosis of ophthalmia neonatorum was established, for which ocular cultures and Gram staining were performed. No bacterial growth was noted, and polymerase chain reaction (PCR) testing for Chlamydia trachomatis, Neisseria gonorrhea, and herpes simplex were negative. Nasopharyngeal and conjunctival SARS-CoV-2 PCR were positive. Given the identification of SARS-CoV-2 illness, lack of other underlying bacterial or viral etiology on testing, and the well-documented ability for SARS-CoV-2 to cause conjunctivitis, the clinical picture was supportive of ophthalmia neonatorum secondary to SARS-CoV-2. The infant was treated with ceftriaxone and azithromycin prior to culture results. During admission, no systemic findings of Covid-19 illness were observed.

A Narrative Review of Current Understanding and Classification of Dry Eye Disease with New Insights on the Impact of Dry Eye during the COVID-19 Pandemic

Dry eye disease (DED) is a complex, progressive and multifactorial condition that is commonly seen in clinical practice and can be challenging to accurately diagnose. Untreated or suboptimally managed dry eye can progress to severe, chronic disease which may become resistant to treatment. Symptoms include ocular irritation and visual impairment. Patients frequently report negative consequences regarding quality of life (QoL), productivity and psychological wellbeing. Certain lifestyle factors (e.g. use of screen-based devices, air conditioning) can induce or exacerbate symptoms of DED, leading to progressive and debilitating complications. Exposures to such triggers are likely to have increased significantly during the ongoing COVID-19 pandemic with people across the globe living with heightened levels of stress/anxiety while being forced to adapt most aspects of their daily lives (from work and education through to social activities) to accommodate social distancing, primarily through the use digital technologies. This review aims to provide a concise and practical overview of current understanding regarding DED, highlighting proposals for refined diagnostic categories and therapeutic terminologies that are designed to improve identification and management of dry eye as well as reduce or slow disease progression. Finally, the findings of a European survey are shared to illustrate the impact of the COVID-19 pandemic on the lives of people with DED. The survey was conducted during the first lockdown period (March–September 2020) and explored issues relating to psychological wellbeing, QoL and engagement with healthcare services. The results demonstrate the ways in which the pandemic amplified the impact of dry eye on daily life and may be valuable in enhancing understanding among clinicians of the challenges faced by people with DED, which extend beyond the signs and symptoms of disease.

COVID-19 Ocular Manifestations in the Early Phase of Disease

Purpose: To evaluate and establishe the number of patients with ocular manifestations in the early phase of systemic COVID-19 infection.Methods: A cross-sectional study was performed in a COVID-19 referral center regarding ocular findings in patients with COVID-19 in the first few days of the disease. The patients were submitted to a clinical examination, an ophthalmic exam and a RT-PCR for SARS-COV-2.Results: Out of 1740 patients, we reported 108 patients with ocular manifestations. Forty-nine with markedly conjunctivitis had conjunctival swab positive for SARS-COV-2, four of them developed keratitis. There were mostly no evidence of retinopathy nor decrease in visual acuity. They had no marked clinical symptoms, which can contribute and demonstrate that the virus may cause ocular disease as an only finding or in the very early stage of the infection.Conclusion: Patients were in the first days of COVID-19 infection, presented ocular manifestations suggested to be related to the virus and need to be aware of the pathways of transmissions.

Keep Eyes on COVID-19: Ophthalmic Symptoms and Potential Transmission of SARS-CoV-2 through the Oculus

In December 2019, a new coronavirus disease 2019 (COVID-19) emerged and rapidly spread globally, posing a worldwide health emergency. The pathogen causing this pandemic was identified as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). It is well known that SARS-CoV-2 transmits via respiratory droplets and close contact with infected individuals or contaminated items. In addition to these two major transmission routes, other modes of transmission have not been confirmed. Considering that some COVID-19 patients have presented with ocular discomforts and positive SARS-CoV-2 RNA in ocular surfaces, as well as the discovery of the SARS-CoV-2 receptors, angiotensin-converting enzyme 2, and transmembrane protease, serine 2, in the oculus, the ocular surface is now thought to be a possible alternative route of SARS-CoV-2 transmission and a replication site. This review summarizes the evidence connecting COVID-19 with ocular tissues, ocular symptoms during SARS-CoV-2 infection, the potential role of the conjunctiva in SARS-CoV-2 transmission, and the physiopathological mechanisms. Appropriate precautions in ophthalmology departments, including innovative complete and effective patient management plans, protective personal equipment, hand hygiene, and strict personal distance intervals, are essential to effectively minimize the spread of SARS-CoV-2 and control the pandemic.

Ophthalmology-focused publications and findings on COVID-19: A systematic review

PURPOSE

To summarize COVID-19 research endeavors by ophthalmologists/researchers in terms of publication numbers, journals and author countries, and to detail key findings.

METHODS

The LitCovid database was systematically reviewed for ophthalmology-focused COVID-19 articles. The quality of the evidence was assessed for articles investigating conjunctivitis in COVID-19 patients.

RESULTS

There were 21,364 articles in LitCovid on June 12, 2020, of which 215 (1%) were ophthalmology-focused. Of articles on COVID-19 transmission, 3.3% were ophthalmology-focused. Ophthalmology-focused articles were published in 68 journals and originated from 25 countries. The top five countries publishing ophthalmology-focused articles (China, India, United States of America, Italy, and United Kingdom) produced 145/215 (67%) articles. A total of 16 case reports/series from eight countries reported that conjunctivitis can be the initial or the only symptom of COVID-19 infection. Conjunctivitis may occur in the middle phase of COVID-19 illness. A total of 10 hospital-based cross-sectional studies reported that between 0% and 31.6% of COVID-19 patients have conjunctivitis or other ocular conditions, with a pooled prevalence of 5.5% reported in a meta-analysis. Viral RNA was detected in conjunctival swabs of patients with and without ocular manifestations, after resolution of conjunctivitis, after nasopharyngeal swabs turned negative and in retina of deceased COVID-19 patients.

CONCLUSION

Within 3 months of declaring the COVID-19 pandemic, 215 ophthalmology-focused articles were published in PubMed, concentrating on disease manifestations and transmission. The reported presence of conjunctivitis or other ocular conditions in COVID-19 patients is varied. Clinicians should be alert for ocular involvement in COVID-19 infections and possible ocular transmission even in patients without ocular symptoms.

Predictors of incident viral symptoms ascertained in the era of COVID-19

Background

In the absence of universal testing, effective therapies, or vaccines, identifying risk factors for viral infection, particularly readily modifiable exposures and behaviors, is required to identify effective strategies against viral infection and transmission.

Methods

We conducted a world-wide mobile application-based prospective cohort study available to English speaking adults with a smartphone. We collected self-reported characteristics, exposures, and behaviors, as well as smartphone-based geolocation data. Our main outcome was incident symptoms of viral infection, defined as fevers and chills plus one other symptom previously shown to occur with SARS-CoV-2 infection, determined by daily surveys.

Findings

Among 14, 335 participants residing in all 50 US states and 93 different countries followed for a median 21 days (IQR 10–26 days), 424 (3%) developed incident viral symptoms. In pooled multivariable logistic regression models, female biological sex (odds ratio [OR] 1.75, 95% CI 1.39–2.20, p<0.001), anemia (OR 1.45, 95% CI 1.16–1.81, p = 0.001), hypertension (OR 1.35, 95% CI 1.08–1.68, p = 0.007), cigarette smoking in the last 30 days (OR 1.86, 95% CI 1.35–2.55, p<0.001), any viral symptoms among household members 6–12 days prior (OR 2.06, 95% CI 1.67–2.55, p<0.001), and the maximum number of individuals the participant interacted with within 6 feet in the past 6–12 days (OR 1.15, 95% CI 1.06–1.25, p<0.001) were each associated with a higher risk of developing viral symptoms. Conversely, a higher subjective social status (OR 0.87, 95% CI 0.83–0.93, p<0.001), at least weekly exercise (OR 0.57, 95% CI 0.47–0.70, p<0.001), and sanitizing one’s phone (OR 0.79, 95% CI 0.63–0.99, p = 0.037) were each associated with a lower risk of developing viral symptoms.

Interpretation

While several immutable characteristics were associated with the risk of developing viral symptoms, multiple immediately modifiable exposures and habits that influence risk were also observed, potentially identifying readily accessible strategies to mitigate risk in the COVID-19 era.

A comprehensive review on clinical and mechanistic pathophysiological aspects of COVID-19 Malady: How far have we come?

Since its outbreak in 2019, the coronavirus disease (COVID-19) has become a pandemic, affecting more than 52 million people and causing more than 1 million mortalities globally till date. Current research reveals a wide array of disease manifestations and behaviors encompassing multiple organ systems in body and immense systemic inflammation, which have been summarized in this review. Data from a number of scientific reviews, research articles, case series, observational studies, and case reports were retrieved by utilizing online search engines such as Cochrane, PubMed, and Scopus from December 2019 to November 2020. The data for prevalence of signs and symptoms, underlying disease mechanisms and comorbidities were analyzed using SPSS version 25. This review will discuss a wide range of COVID-19 clinical presentations recorded till date, and the current understanding of both the underlying general as well as system specific pathophysiologic, and pathogenetic pathways. These include direct viral penetration into host cells through ACE2 receptors, induction of inflammosomes and immune response through viral proteins, and the initiation of system-wide inflammation and cytokine production. Moreover, peripheral organ damage and underlying comorbid diseases which can lead to short term and long term, reversible and irreversible damage to the body have also been studied. We concluded that underlying comorbidities and their pathological effects on the body contributed immensely and determine the resultant disease severity and mortality of the patients. Presently there is no drug approved for treatment of COVID-19, however multiple vaccines are now in use and research for more is underway.

Quantitative Evaluation of Aerosol Generation from Non-contact Tonometry and its Correlation with Tear Film Characteristics

INTRODUCTION

Ophthalmologists are inevitably exposed to tears and ocular discharge during ophthalmologic examinations and are at high risk for SARS-CoV-2 infection. To understand the role of aerosols in disease transmission, we adopted a prospective cross-sectional study design and investigated the count and size distribution of aerosols generated by a non-contact tonometer and its correlation with individual tear film characteristics.

METHODS

This study constituted two parts. The study population included outpatients who underwent an intraocular pressure examination in an intraocular pressure examination room (Part I) and 20 participants who underwent an intraocular pressure examination in a laboratory (Part II). The following main outcomes were measured: aerosol counts at 0, 50, 100, 150, and 200 cm from the non-contact tonometer (Part I); aerosol counts after each participant underwent non-contact tonometry, and lipid layer thickness score and tear film break-up time (Part II).

RESULTS

The aerosol count decreased with increasing distance from the tonometer. The aerosol count at 0 cm had the highest value compared to that at other distances. For aerosols of diameters 0.25-0.5 μm and 0.5-1.0 μm, the count decreased at 50 cm and remained stable at further distances. For aerosols of diameters 1.0-2.5 μm and ≥ 2.5 μm, the count dropped progressively at all five distances. The aerosol count from each tonometer correlated positively with the lipid layer thickness score (r = 0.490, P = 0.028), whereas the aerosol count correlated negatively with the tear film break-up time (r =  - 0.675, P = 0.001).

CONCLUSIONS

Aerosols tended to coagulate during diffusion. A 50-cm distance from the tonometer could confer safety from aerosols with < 1.0-μm diameter. Aerosols generated during non-contact tonometry could contain a lipid layer component. Moreover, tear film stability could affect aerosol generation. Protective eyewear is recommended for reducing infection risk from aerosols. Individual tear film characteristics should be considered during non-contact tonometry.

Clinical Manifestations of COVID-19

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the third coronavirus causing an outbreak in the twenty-first century. It is related to a contagious coronavirus disease (COVID-19), which its high pace of spreading allowed it to lie to the whole world and be turned into a pandemic only a few months after the identification of the first case. Currently, the reverse transcription-polymerase chain reaction (RT-PCR) test of throat swap is the gold standard of diagnosis; however, several studies have reported false-negative results with non-ideal sensitivity. Because this pandemic constitutes a significant burden on global healthcare systems and due to the high transmission rate of the virus, an accurate diagnosis algorithm is needed to reduce the missing case number. A comprehensive clinical examination and taking a history of all systems (not just limited to the respiratory system) combined with hematologic laboratory tests and chest imaging can lead to a sensitive diagnosis, severity assessment, and RT-PCT test interpretation. This chapter focuses on clinical characteristics, hematologic laboratory, and chest imaging features in COVID-19.

Comparative Evaluation of Tears and Nasopharyngeal Swab for SARS-CoV-2 in COVID-19 Dedicated Intensive Care Unit Patients

Purpose: To compare the cycle threshold (Ct) values of tears and nasopharyngeal (NP) swab in severe COVID-19 ICU patients with positive NP swabs.Procedure: A cross-sectional study for the detection of SARS-CoV-2 by real-time RT-PCR on simultaneously collected NP swabs and tears was performed. Detailed demographic profile, including comorbidities, ocular, and systemic features were analyzed.Results: In the 78 cases, the mean tear positivity was 26.92% (21/78), 2 tear samples being positive despite a negative NP swab. The mean Ct value of tears and NP were 28.17 ± 4.76 and 23.71 ± 6.19, respectively (p= .003). None of the cases had ocular findings or relationship between tear positivity and comorbidity.Conclusions: The viral load of tears is less than the NP secretions with the possibility of prolonged shedding in tears. Tears act as an additional source of contact transmission in ICU that can possibly be decreased by frequent hand hygiene by the patient.Abbreviations: SARS-CoV-2: Severe acute respiratory syndrome coronavirus; RT-PCR: Real-time Reverse transcriptase-polymerase chain reaction; COVID-19: Corona virus disease 2019; ICU: Intensive care unit; RdRp: RNA-dependent RNA polymerase; ORF 1b: Open reading frame 1b; AIIR: Airborne infection isolation room; HCW: Health care workers; VTM: viral transport media; NP: Nasopharyngeal swab; PPE: Personal protective equipment.

Review of Current COVID-19 Diagnostics and Opportunities for Further Development

Diagnostic testing plays a critical role in addressing the coronavirus disease 2019 (COVID-19) pandemic, caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Rapid and accurate diagnostic tests are imperative for identifying and managing infected individuals, contact tracing, epidemiologic characterization, and public health decision making. Laboratory testing may be performed based on symptomatic presentation or for screening of asymptomatic people. Confirmation of SARS-CoV-2 infection is typically by nucleic acid amplification tests (NAAT), which requires specialized equipment and training and may be particularly challenging in resource-limited settings. NAAT may give false-negative results due to timing of sample collection relative to infection, improper sampling of respiratory specimens, inadequate preservation of samples, and technical limitations; false-positives may occur due to technical errors, particularly contamination during the manual real-time polymerase chain reaction (RT-PCR) process. Thus, clinical presentation, contact history and contemporary phyloepidemiology must be considered when interpreting results. Several sample-to-answer platforms, including high-throughput systems and Point of Care (PoC) assays, have been developed to increase testing capacity and decrease technical errors. Alternatives to RT-PCR assay, such as other RNA detection methods and antigen tests may be appropriate for certain situations, such as resource-limited settings. While sequencing is important to monitor on-going evolution of the SARS-CoV-2 genome, antibody assays are useful for epidemiologic purposes. The ever-expanding assortment of tests, with varying clinical utility, performance requirements, and limitations, merits comparative evaluation. We herein provide a comprehensive review of currently available COVID-19 diagnostics, exploring their pros and cons as well as appropriate indications. Strategies to further optimize safety, speed, and ease of SARS-CoV-2 testing without compromising accuracy are suggested. Access to scalable diagnostic tools and continued technologic advances, including machine learning and smartphone integration, will facilitate control of the current pandemic as well as preparedness for the next one.

An Eye on COVID-19: A Meta-analysis of Positive Conjunctival Reverse Transcriptase-Polymerase Chain Reaction and SARS-CoV-2 Conjunctivitis Prevalence

SIGNIFICANCE

This analysis and review demonstrate that, although emerging data indicate that the prevalence of severe acute respiratory coronavirus 2 (SARS-CoV-2) on the ocular surface and coronavirus disease 2019 (COVID-19) conjunctivitis is rare, the ocular surface remains of interest as a potential inoculation and transmission site for SARS-CoV-2. Continued safety precautions should be taken as more data become available.COVID-19, caused by SARS-CoV-2, is a novel, global pandemic that has infected millions and, up to this point, caused more than two million fatalities worldwide. The ocular surface has become of interest as a possible vector for transmission by acting as a direct inoculation site, being a conduit for the virus into the respiratory system or as a method of transmission from potentially infected conjunctiva or tears. The components necessary for SARS-CoV-2 to theoretically infect ocular tissues are present: binding receptors (angiotensin-converting enzyme 2 and cluster of differentiation 147) and mechanisms for cell entry (transmembrane protease serine 2 and cathepsin L). This meta-analysis of COVID-19 prevalence data indicates that SARS-CoV-2 RNA has been infrequently found in conjunctival samples when tested with reverse transcriptase-polymerase chain reaction. This review estimates the prevalence of SARS-CoV-2 on the ocular surface and prevalence of conjunctivitis in patients with laboratory-confirmed COVID-19. There is much to be learned regarding ocular tropism of SARS-CoV-2.