Testing for severe acute respiratory coronavirus 2 (SARS-CoV-2) in human tears can help spot infections that go undetected with current nose-pharyngeal molecular swabs.
Between April and May 2020, the researchers collected tears’ samples from both eyes of 108 patients, 91 of which had been diagnosed with COVID-19 and hospitalized at three Intensive Care Units (ICUs) in Northern Lombardy. Overall, the virus was detected on the ocular surface in 52 out of 91 patients.
The authors believe the most likely explanation for the virus to show up in the eyes is that SARS-CoV-2 could ride on atmospheric particulate matter and remain in the atmosphere for hours or days, especially in a non-windy and polluted area, like the Lombardy’s Po Valley. Once infected by particulates, tears would reach the throat, potentially infecting both the upper and lower respiratory systems.