Conclusion
ADVERSE EFFECTS
PDT treatment was well tolerated, and no serious adverse effects were detected. Nasal PDT enhances SARS-CoV-2 viral clearance in mild COVID-19 patients, even in vaccinated individuals, rapidly decreasing infectivity. Nasal PDT decelerates the decline of SARS-CoV-2 specific T-cell immune responses in vaccinated individuals infected with Omicron variant.