Ocular manifestations of COVID-19

Abstract

SARS-CoV-2 (severe acute respiratory syndrome-coronavirus-2) is a coronavirus that causes COVID-19 (coronavirus disease 2019) with mild to severe respiratory illness. It is a highly contagious disease transmitted via respiratory droplets and other routes still being investigated either through a direct or indirect contact with infected people or contaminated surfaces. It is well known that coronaviruses (CoVs) can cause a variety of ocular pathologies in animals, including conjunctivitis, anterior uveitis, retinitis, and optic neuritis, many of which are severe. However, there is no evidence to support the presence of the SARS-CoV-2 in the eye tissue of asymptomatic patients, even if the symptomatic incidence is low.
COVID-19 has spread throughout the continents and has become a global threat to public health as it posed the risk of rapidly overloading health care systems and causing grave mortality worldwide. As a result of this, the World Health Organization (WHO) on March 11, 2020 declared coronavirus a global pandemic.
While diagnostic and therapeutic efforts have been focused on respiratory complications of the disease, several studies have described a few cases with initial ocular symptoms followed by systemic symptoms of the disease. SARS-CoV-2 RNA has been found in tears of the infected patients, and reports suggest that the ocular surface could serve as a portal of entry and a reservoir for viral transmission. Although, COVID-19 has been clinically associated with mild conjunctivitis, which can be the first and only symptom of the disease, subtle retinal changes like hyperreflective lesions in the inner layers on optical coherence tomography (OCT), cotton-wool spots, and microhaemorrhages have also been reported. It has also been associated with an increased incidence of systemic diseases like diabetes mellitus and Kawasaki disease, which are particularly relevant for ophthalmologists due to their potentially severe ocular manifestations.