Inclusion Criteria:  Patients over 18 years of age Confirmed positive test result for SARS-CoV-2 within 14d Mechanically ventilated (first intubation since positive SARS-CoV-2 test) Endotracheal tube inner diameter at least 7.5 mm  Exclusion Criteria:  Unable to provide informed consent (or surrogate) Enrolled in a therapeutic clinical trial for COVID-19 that does not allow recruitment in other trials. Pregnant women. While not an exclusion criterion, special care should be exercised in treating patients who are receiving concomitant therapy (either topically or systemically) with known photosensitizing agents such as anthralin, coal tar or coal tar derivatives, griseofulvin, phenothiazines, nalidixic acid, fluoroquinolone antibiotics, halogenated salicylanilides (bacteriostatic soaps), sulfonamides, tetracyclines, thiazides and certain organic staining dyes such as methylene blue, toluidine blue, rose bengal, and methyl orange.