SARS-CoV-2: Is it present in the conjunctiva?

Abstract

The Orthocoronavirinae family was discovered in the 1960s. These are enveloped viruses with positive single-stranded RNA, and their genome size varies approximately between 26 and 32 kb, being the largest genome for an RNA virus. In Mexico, the first reported case was that of a person from Italy. Taking this first case as day 1, the cases have been increasing and, at the time of writing this article, there were 133,974 infected people and 15,944 deaths. The conjunctiva has been proposed as a route of entry for SARS-CoV-2. However, in a search for coronavirus genetic material in tear and conjunctiva samples, patients who did not show conjunctivitis were negative for the presence of viral genetic material, and only one person was positive, both in tear and conjunctiva samples. Negative results for SARS-CoV-2 RNA in tears and conjunctival secretions could indicate that the virus does not replicate in conjunctival epithelia, but could be present in undetectable amounts, which does not rule out that it can be transmitted through the conjunctiva.