Conjunctival Findings in Patients With Coronavirus Disease 2019—Reply

In Reply We thank the readers for their interest in our previous report on the ocular findings of patients with coronavirus disease 2019 (COVID-19).¹ With great respect, we carefully have read those letters and we provide our responses.

Our study¹ was a cross-sectional study in which each patient was at a different stage of COVID-19 when reverse transcription–polymerase chain reaction testing was performed. We only enrolled patients who were hospitalized within the week and had ocular symptoms or signs present after COVID-19. When collecting specimens, we recorded ocular histories with questionnaires and clinicians (nonophthalmologists) examined eyes with bedside flashlights. If possible, eye photographs were taken by cell phone in cases with ocular abnormalities. To minimize the spread of transmission, ophthalmologists were not allowed to enter the isolation ward, and no enrolled patients received any professional ocular therapy.

Our data¹ showed that among 38 patients, 12 had ocular abnormalities (eg, ocular symptoms and/or signs). Similar findings were reported by Hong et al² in Zhejiang, China, and Chen et al³ in Wuhan, China. As the readers have questioned, we do not think those ocular findings were specific to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. In our study, 2 patients had positive findings on reverse transcription–polymerase chain reaction testing that were possibly associated with SARS-CoV-2 infection. Six (including these 2 patients) of 12 patients were treated with ventilators. We agree with Wan and colleagues’ comments⁴ that the constellation of manifestations were also possibly because of the use of ventilators, electrolyte disturbances, and fluid overload. In addition, secondary bacterial infection, long-term short-distance reading, and dry eye may also be the causes of ocular abnormalities.^2,4 Thus, the diagnosis of viral conjunctivitis was not accurate because of the absence of viral nucleotides found.

Recently, studies have shown that angiotensin-converting enzyme 2, a receptor of SARS-CoV-2, is expressed in the cornea and conjunctiva, suggesting that ocular surface tissue is a potential target tissue infected by SARS-CoV-2.⁵ Similarly, some case reports, studies in cells and animals, and epidemiological investigations have shown that the eye is a transmission route of SARS-CoV-2 infection via invasion of the ocular surface tissue or transportation to the respiratory system through the nasolacrimal duct.^5,6 Thus, we believe that the conjunctiva is a preferred portal of entry for SARS-CoV-2 to cause COVID-19. In addition, high levels of angiotensin-converting enzyme 2 in the retina and intraocular fluids have been reported,⁶ which may result in intraocular inflammation, although we have found no literature on this topic. We have stated that 12 patients had ocular surface manifestations, in contrast with the intraocular damage that may lead to blurry vision.

In conclusion, we found that 2 of the 38 patients yielded positive findings in their conjunctiva and the ocular symptoms and/or signs commonly appeared in patients with severe systemic disease. Combined with the up-to-date study results and our report,¹ it appears that the eye plays as a transmission route of SARS-CoV-2 infection, which might, in turn, serve as a source of its spread, especially in those of patients with critical illness. We believe that eye protection is very necessary, especially for medical staff.

Corresponding Author: Liang Liang, MD, Department of Ophthalmology, Yichang Central People’s Hospital, The First College of Clinical Medical Science, Three Gorges University, Yichang 443003, China (liangliang419519@163.com); and Kaili Wu, MD, Zhongshan Ophthalmic Center, State Key Laboratory of Ophthalmology, Sun Yat-Sen University, Guangzhou 510060, China (wukaili@maill.sysu.edu.cn).

Published Online: December 23, 2020. doi:10.1001/jamaophthalmol.2020.5822

Conflict of Interest Disclosures: None reported.