Perhaps it’s just good practice to use the peroxide regime after getting tested just in case there is accidentai or intentional contamination of swabs?
I’ve wondered the same about colloidal silver. If I’ve been in contact with a person who’s got a cold, I gargle with it, and also have some in a spray bottle which I’ll occasionally “snort” some of. (I haven’t gotten sick in a good long time - decades, with the exception of a cold that lasted about 12-16 hours.)
I had not thought about it till now. My hubby had a terribly bad respiratory infection for 6-8 weeks last fall. He refused to go to the doc or be tested. I also had what I thought to be a cold the first day he was sick. My one day to his 6-8 weeks. But I rinse my mouth with peroxide and on other days spray mouth with colloidal silver. Perhaps that was our difference.