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

Ocular symptoms in COVID-19 patients with a history of hospitalization in the first pandemic wave in Styria, Austria

Purpose

Our study aimed to investigate the prevalence and timing of ocular surface manifestations in hospitalized COVID-19 patients, providing insights into the occurrence of eye involvement before, during, or after the illness. This study contributes to understanding the extent of ocular involvement in COVID-19, which has been suggested to occur due to potential viral entry through the eyes.

Methods

451 confirmed COVID-19 patients had a history of hospitalization in Styria, Austria. The study included 176 patients aged 18-95 years who tested positive for SARS-CoV-2 in nasopharyngeal swabs by RT-PCR and received treatment at two hospitals. Telephone interviews were conducted after recovery, focusing on ocular symptoms and medical history (openMEDOCS).

Results

Seventeen percent (n=30) reported new-onset ocular symptoms in the context of COVID-19. Patients with ocular symptoms were younger (p<0.001). Sore throat (p=0.013) and high fever (p=0.038) were significantly more prevalent in patients with new-onset ocular symptoms. Persistent ocular symptoms beyond the duration of hospitalization affected more than half (56.7%) of the participants with new-onset ocular symptoms. However, there were no differences in blood parameters, lung imaging, or comorbidities between groups with and without ocular symptoms.

Conclusions

In hospitalized COVID-19 patients, ocular symptoms occur with a significant prevalence of 17%. Younger age (p<0.001) and the presence of sore throat (p=0.013) are associated with an increased risk of developing new-onset ocular symptoms in the context of COVID-19.

Exploring the role of the ocular surface in the lung-eye axis: Insights into respiratory disease pathogenesis

Chronic respiratory diseases (CRDs) represent a significant proportion of global health burden, with a wide spectrum of varying, heterogenic conditions largely affecting the pulmonary system. Recent advances in immunology and respiratory biology have highlighted the systemic impact of these diseases, notably through the elucidation of the lung-eye axis. The current review focusses on understanding the pivotal role of the lung-eye axis in the pathogenesis and progression of chronic respiratory infections and diseases. Existing literature published on the immunological crosstalk between the eye and the lung has been reviewed. The various roles of the ocular microbiome in lung health are also explored, examining the eye as a gateway for respiratory virus transmission, and assessing the impact of environmental irritants on both ocular and respiratory systems. This novel concept emphasizes a bidirectional relationship between respiratory and ocular health, suggesting that respiratory diseases may influence ocular conditions and vice versa, whereby this conception provides a comprehensive framework for understanding the intricate axis connecting both respiratory and ocular health. These aspects underscore the need for an integrative approach in the management of chronic respiratory diseases. Future research should further elucidate the in-depth molecular mechanisms affecting this axis which would pave the path for novel diagnostics and effective therapeutic strategies.

Dyschromatopsia and contrast sensitivity changes in COVID-19 patients

PURPOSE

To evaluate the alterations in the psycho-physical tests, contrast sensitivity (CS) and hue discrimination (total estimation score, TES) in COVID-19 patients.

METHODS

A prospective case-control study was undertaken in 2021-22 to look at CS and TES among COVID-19 patients and RT-PCR negative normal subjects by a mobile app "smart optometry" and X-Rite's free online version of Farnsworth-Munsell 100 hue test. Strict visual acuity (minimum of 6/9 equivalent on Snellen) and other clinical parameters were used as exclusion criteria to filter potentially confounding pre-receptoral co-morbid conditions. The effect of mismatch in recruiting age and sex matched controls during the pandemic were analyzed by multivariate linear regression.

RESULT

One-way ANOVA ruled out any influence of gender on CS and TES; however, there was significant difference in the TES on Mann Whitney U test (TES- 2.95 +/- 3.8 for cases; 0.30 +/- 1.1 for controls; p <0.001) and it persisted after accounting for age. Six controls with breakthrough infections had a significant deterioration in TES (Mean scores -3.0; 95% CI = -5.89 to -0.11; p = 0.04) on paired t test. Qualitative analysis showed that S-cone mediated deficiencies outnumber those affecting M-L cone mediated deficiencies. Among 53 subjects exhibiting three sensory features, anosmia, loss of taste and dyschromatopsia, nine (16.98%) had all features concurrently.

CONCLUSION

The study demonstrates that COVID-19 infection leads to altered TES representing dyschromatopsia -an ocular counterpart of anosmia, with little difference on CS.

Management of COVID-19 in Ophthalmology

From its outbreak in early 2020, the new SARS-CoV-2 infection has deeply affected the entire eye care system for several reasons. Since the beginning of the COVID-19 pandemic, ophthalmologists were among the "high-risk category" for contracting the SARS-CoV-2 infection based on the notion that the eye was suspected to be a site of inoculation, infection, and transmission. Clinical ophthalmologists have been required to learn and promptly recognize the ocular manifestations associated with the COVID-19 disease, with its treatments and vaccinations. Restriction measures, lockdown periods, guidelines to prevent SARS-CoV-2 infection transmission, and the use of telemedicine and artificial intelligence modalities have induced profound modifications. These changes, which are most likely to be irreversible, influence routine clinical practice, education, and research, thus giving rise to a "new ophthalmology in the COVID era". This book chapter aims to provide several notions regarding COVID-19 in ophthalmology, including the SARS-CoV-2 virus infection and transmission modalities; the ocular manifestation associated with the COVID-19 disease; the drugs and vaccines used for COVID-19; the precautions adopted in the ophthalmic practice to limit the spread of the virus; the consequences of the pandemic on the ophthalmic patients, clinicians, and the entire eye care system; and, the future of ophthalmology in the era of "COVID new normal".

Manifestations of coronavirus infection disease-19 in anterior eye segment: An up-to-date review

Coronavirus infection disease-19 (COVID-19) is a worldwide catastrophic emergency that first appeared in late 2019, in Wuhan, China. COVID-19 is a multitropism disease that first affects lung tissue. However, extrapulmonary manifestations have been suspected from the first COVID-19 cases. The ocular signs and symptoms were from the early changes that occur during the course of the disease. Changes in the anterior eye segment have a relatively higher incidence than the posterior eye segment. Of which, conjunctivitis, COVID-19 pharyngioceratoconjuctivitis, iridocyclitis, corneal punctate epitheliopathy, and pathomorphological changes in the physio-anatomy of the anterior eye segment. The potential pathogenesis includes direct penetration of the virus into the eye (conjunctiva, lumbus, and cornea) or due to a systemic pathway through viremia, as well as due to autoimmune antibodies against the ocular structure (immune privilege). The presence of ocular manifestations of the external anterior fibrous layer suggests a mild course of the disease.

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.

Incidence and clinical characteristic of ocular surface manifestation: an evaluation of conjunctival swab results in Corona Virus 2019 (COVID-19) patients in Jakarta, Indonesia

OBJECTIVES

This study aimed to investigate the spectrum of ocular characteristics and viral presence in the conjunctival swab of patients with COVID-19.

METHODS

In this cross-sectional study, fifty-three patients were recruited from two COVID-19 referral hospitals in Jakarta (Cipto Mangunkusumo Hospital and Persahabatan Hospital) from July 2020 to March 2021. The inclusion criteria were patients who were suspected of or confirmed cases of COVID-19 with or without ocular symptoms. Demographic data, history of COVID-19 exposure, underlying medical condition, systemic symptoms, ocular symptoms, supporting laboratory results, reverse-transcriptase polymerase chain reaction (RT-PCR) of naso-oropharyngeal (NOP) swab and conjunctival swab were collected.

RESULTS

Fifty-three patients who were suspected, probable or confirmed cases of Covid-19 were included. Forty-six out of 53 patients (86.79%) tested positive for either Covid-19 antibody rapid test or naso-oropharyngeal (NOP) swab. Forty-two patients tested positive for NOP swab. Fourteen out of 42 patients (33.33%) experienced symptoms of ocular infection including red eye, epiphora, itchy eyes, and eye discharge. None of these patients were tested positive for conjunctival swab. Two out of 42 patients (4.76%), who were tested positive for conjunctival swab, did not experience any ocular symptoms.

CONCLUSIONS

Establishing the relationship between Covid-19 infection, ocular symptoms, and presence of SARS-CoV-2 virus on the ocular surface proves to be challenging. In Covid-19 patients, ocular symptoms did not warrant a positive conjunctival swab result. On the contrary, a patient without ocular symptoms can also have detectable presence of SARS-CoV-2 virus on the ocular surface.

Covid-19 and its relation to the human eye: transmission, infection, and ocular manifestations

BACKGROUND

The world is suffering from a new strain of the coronavirus family-Covid-19. This virus strain affected different organs in the human body with a wide range of mild symptoms and moderate signs to severe and deadly ones. Multiple organs can be infected, and one of these organs is the eye. The eye is a vital organ that consists of vascular tissues and is connected to the respiratory tract through the tears and the nasolacrimal duct.

METHODS

Recent papers and research from PubMed, Researchgate, and Google Scholar were cited and thoroughly discussed. These papers were chosen based on their relevancy, reliability, publication year, published journal, and ease of accessibility to the paper itself.

RESULTS

The theory concluded that the ocular surface might consider a pathway for the virus attack and infection causation through the tears and the angiotensin-converting enzyme 2 located in the eye. This article thoroughly reviewed the history, the existing aspects of Covid-19, the ocular system features, and the claims about the possible involvement of the eye in the virus transmission along with the eye infection. There was no consensus on the eye's involvement theory.

CONCLUSION

The authors highlighted the extra work and research needed to be conducted to prove or deny these claims to provide a better understanding of the immune response of the eye to Covid-19 infection.

Is orbital wall fracture associated with SARS-CoV-2 ocular surface contamination in asymptomatic COVID-19 patients?

Objectives

To assess the relationship between orbital wall fractures connecting to  paranasal sinuses (OWF-PNS) and SARS-CoV-2 ocular surface contamination (SARS-CoV-2-OSC) in asymptomatic COVID-19 patients.

Methods

This was a prospective case–control study enrolling two asymptomatic COVID-19 patient cohorts with vs. without OWF-PNS in the case–control ratio of 1:4. All subjects were treated in a German level 1 trauma center during a one-year interval. The main predictor variable was the presence of OWF-PNS (case/control); cases with preoperative conjunctival positivity of SARS-CoV-2 were excluded to rule out the possibility of viral dissemination via the lacrimal gland and/or the nasolacrimal system. The main outcome variable was laboratory-confirmed SARS-CoV-2-OSC (yes/no). Descriptive and bivariate statistics were computed with a statistically significant P ≤ 0.05.

Results

The samples comprised 11 cases and 44 controls (overall: 27.3% females; mean age, 52.7 ± 20.3 years [range, 19–85]). There was a significant association between OWF-PNS and SARS-CoV-2-OSC (P = 0.0001; odds ratio = 20.8; 95% confidence interval = 4.11–105.2; R-squared = 0.38; accuracy = 85.5%), regardless of orbital fracture location (orbital floor vs. medial wall versus both; P = 1.0).

Conclusions

Asymptomatic COVID-19 patients with OWF-PNS are associated with a considerable and almost 21-fold increase in the risk of SARS-CoV-2-OSC, in comparison with those without facial fracture. This could suggest that OWF-PNS is the viral source, requiring particular attention during manipulation of ocular/orbital tissue to prevent viral transmission.

Ocular adverse effects of COVID-19 vaccines: A systematic review

The COVID-19 pandemic has led to the development and rollout of several vaccines worldwide at unprecedented pace. This systematic review of published literature has been undertaken to spread awareness among general physicians and ophthalmologists about the various reported adverse effects in the eye following COVID-19 vaccination. A systematic search was performed on 25 January 2022 through PuBMed, Medline and Google scholar for publications on ocular adverse effects after COVID-19 vaccination. One brief communication, four retrospective case series, sixteen case reports, and five letters to editors were included. Ocular manifestations most commonly appear in the uvea and retina. Other manifestations are seen on the eyelid, cornea and ocular surface, and in cranial nerves innervating the eye. The incidence rate of these manifestations is quite low after COVID-19 vaccinations. Our systematic review meticulously enumerates various adverse effects of COVID -19 vaccine on the eye. Most of these adverse effects are transient and observed to resolve without any sequelae except for cases of retinal and ophthalmic vascular occlusions and corneal graft rejections. An emphasis on close follow-up and a need to delay vaccination and modified therapy to control flare up of signs and symptoms in certain sub-populations, Graves' disease (autoimmune etiology), pre-existing uveal inflammation and corneal graft cases are warranted. We need long-term, larger, multicentric studies to substantiate our findings and establish the causal relationship with certainty. Mass vaccinations to curb this pandemic after outweighing the ocular risks associated with it is warranted.

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.

Aleatory-aware deep uncertainty quantification for transfer learning

The user does not have any idea about the credibility of outcomes from deep neural networks (DNN) when uncertainty quantification (UQ) is not employed. However, current Deep UQ classification models capture mostly epistemic uncertainty. Therefore, this paper aims to propose an aleatory-aware Deep UQ method for classification problems. First, we train DNNs through transfer learning and collect numeric output posteriors for all training samples instead of logical outputs. Then we determine the probability of happening a certain class from K-nearest output posteriors of the same DNN in training samples. We name this probability as opacity score, as the paper focuses on the detection of opacity on X-ray images. This score reflects the level of aleatory on the sample. When the NN is certain on the classification of the sample, the probability of happening a class becomes much higher than the probabilities of others. Probabilities for different classes become close to each other for a highly uncertain classification outcome. To capture the epistemic uncertainty, we train multiple DNNs with different random initializations, model selection, and augmentations to observe the effect of these training parameters on prediction and uncertainty. To reduce execution time, we first obtain features from the pre-trained NN. Then we apply features to the ensemble of fully connected layers to get the distribution of opacity score during the test. We also train several ResNet and DenseNet DNNs to observe the effect of model selection on prediction and uncertainty. The paper also demonstrates a patient referral framework based on the proposed uncertainty quantification. The scripts of the proposed method are available at the following link: https://github.com/dipuk0506/Aleatory-aware-UQ.

Ocular Manifestations after Receiving COVID-19 Vaccine: A Systematic Review

The coronavirus disease 2019 (COVID-19) pandemic has had profound and lasting consequences since 2019. Although vaccines against COVID-19 have been developed and approved under emergency use authorization, various adverse events have also been reported after COVID-19 vaccination. This review was undertaken to help clinicians recognize the possible manifestations and systemic pathogenesis, especially those related to the eye, after receiving COVID-19 vaccination. A systemic search was performed on 22 August 2021 through Embase, Medline, and Cochrane Library for publications on ocular manifestations after COVID-19 vaccination. Two case-control studies/retrospective cohort studies, one cross-sectional study, three case series, sixteen case reports, two images, and seven letters were included. Ocular manifestations after receiving COVID-19 vaccines may appear on the eyelid, cornea and ocular surface, retina, uvea, nerve, and vessel. The ocular manifestations occurred up to forty-two days after vaccination, and vaccine-induced immunologic responses may be responsible. Although the incidence rate of ocular symptoms is considerably lower in the vaccinated subjects than in COVID-19 patients, physicians should be aware of the possible associations between COVID-19 vaccines and ocular symptoms for the early diagnosis and treatment of vision problems or life-threatening complications.

Viral S protein histochemistry reveals few potential SARS-CoV-2 entry sites in human ocular tissues

Despite the reported low expression of the primary SARS-CoV-2 receptor ACE2 in distinct ocular tissues, some clinical evidence suggests that SARS-CoV-2 can infect the eye. In this study, we explored potential entry sites for SARS-CoV-2 by viral S protein histochemistry on various ocular tissues and compared the staining patterns with RNA and protein expression of TMPRSS2 and ACE2. Potential viral entry sites were investigated by histochemistry using tagged recombinant viral S protein on 52 ocular tissue samples including specimens of the cornea, conjunctiva, lid margin, lacrimal gland tissue, retina, choroid, and RPE. In addition, ACE2 and TMPRSS2 immunohistochemistry were performed on the same ocular tissue, each with distinct antibodies binding to different epitopes. Lung tissue samples were used as positive controls. Finally, bulk RNA sequencing (RNA-Seq) was used to determine the expression of ACE2 and its auxiliary factors in the tissues mentioned above. S protein histochemistry revealed a positive staining in lung tissue but absent staining in the cornea, the conjunctiva, eye lid samples, the lacrimal glands, the retina and the optic nerve which was supported by hardly any immunoreactivity for ACE2 and TMPRSS2 and scarce ACE2 and TMPRSS2 RNA expression. Negligible staining with antibodies targeting ACE2 or TMPRSS2 was seen in the main and accessory lacrimal glands. In contrast, ocular staining (S protein, ACE2, TMPRSS2) was distinctly present in pigmented cells of the RPE and choroid, as well as in the ciliary body and the iris stroma. S protein histochemistry revealed hardly any SARS-CoV-2 entry sites in all ocular tissues examined. Similarly, no significant ACE2 or TMPRSS2 expression was found in extra- and intraocular tissue. While this study suggest a rather low risk of ocular infection with SARS-CoV-2, it should be noted, that potential viral entry sites may increase in response to inflammation or in certain disease states.