Eyes vs COVID-19 infection: the gates of infection or one of the target organs?

The bulk of publications devoted to coronavirus infection (COVID-19) is devoted to lung damage, less often to neurological and gastroabdominal disorders. Significantly less attention is paid to eye damage. Conjunctivitis is usually described. Considering the pathogenesis of COVID-19, the eye is defined as the entrance gate to infection. However, the anatomical and immunological characteristics of the eye allow us to talk about the essential role of the eye in the spread of infection throughout the body and damage to the eye as a target organ. COVID-19 has a tropism for eye tissue. The eye has a large surface in contact with virus-containing microaerosols in the air and contaminated hands. Attachment of the virus occurs on the conjunctiva, cornea, retina due to angiotensin converting enzyme 2 (ACE2) receptors and some other receptors, lipophilic periocular skin and superficial tear film. From there, through the tear-nasal duct, the virus enters the nose under the lower nasal concha, from where it is transferred through the nasopharynx and oropharynx to the lungs and intestines. Simultaneously with the transfer of the virus, a specific inflammatory process in the form of conjunctivitis and lacrimation is also played out. The hematogenous introduction of the virus into the retina is manifested by microthrombosis of its vessels, edema. In children, the density of the receptors that ensure the fixation of the virus is significantly lower than in adults. COVID-19 eye damage may be the debut of systemic manifestation. Therefore, ophthalmologists who are in close contact with patients with conjunctivitis, initially perceived as adenoviral, are most at occupational risk. Given the adhesive, transmissible and pathogenetic significance of the eye in the development of COVID-19, it is necessary to evaluate the importance of aerosols reaching the eyes and drops (ACE2 receptor blockers, zinc, azithromycin, etc.) for the prevention and treatment of COVID-19.

children, eye diseases, coronavirus