Glasses Against Transmission of SARS-CoV-2 (COVID-19) in the Community (GLASSY)

A systematic review of observational studies indicated that eye protection may be an effective measure to prevent SARS-CoV-2 infections. Randomized trials are needed to assess whether the observed associations are caused by protection of the eye or confounding factors such as other systematic differences between users and non-users of eye protection, co-interventions, or changes in COVID-19 incidence when comparisons were done over time.

This is a pragmatic, virtual, parallel group, 1:1 randomized, superiority trial. The researchers will recruit and randomize participants via an online portal. The trial will be fully remote and virtual without any personal interaction between investigators and participants. All members of the public are eligible who confirm that they are at least 18 years of age, do not regularly wear glasses, have not contracted COVID-19 since December 15th 2021, and are willing to be randomized to wear, or not wear glasses in public when close to other people, for a 2-week period. Persons who are dependent on visual aids but typically use contact lenses are eligible. The participants will be randomized (1:1) to wear glasses (sunglasses or other types of glasses) in public spaces when close to others (public transport, shopping centers etc.), or to the control group. The control group will be asked not to wear glasses in public spaces when close to others. The primary outcome is positive test for COVID-19.

The researchers aim to include about 25,000 participants to have a statistical power of 80% to detect a relative risk reduction of 25% for the primary outcome.