COVID-19 pandemic and impact of universal face mask wear on ocular surface health and risk of infection.

Universal mask wear is an effective public health intervention to reduce SARS-Cov-2 transmission, especially in enclosed public spaces and healthcare environments. Concerns have been raised about possible transmission of the SARS-Cov-2 through ocular secretions, leading to enhanced protective measures during ophthalmic procedures. However, there is some evidence for air jets from the upper edge of the surgical mask to the ocular surface, especially when the mask is not well fit. Prolonged airflow towards the ocular surface during expiration may alter tear-film stability, leading to hyperosmolarity and ocular surface inflammation. This also raises the question of whether the ocular surface is contaminated with oral flora from airflow directed toward the eyes, thus increasing the risk of ocular infection. Herein we review the impact of patient face mask wear on the ocular surface, eyelids and risk of ocular infection, particularly during ocular surgery. There is some evidence for increased incidence of dry eye or eyelid disease during periods of mandatory face mask wear. While high daily exposure is consistent with a direct association, this should be mitigated by various cofounding factors which could also affect the ocular health during the COVID-19 pandemic. An increased risk of post-intravitreal injection endophthalmitis, possibly due to face mask wear by the patient, including culture-positive endophthalmitis, has been reported in one retrospective study. Several measures have been shown to prevent or limit the risk of developing dry eye disease or exacerbation, eyelid cyst, and ocular infection during intravitreal injections.