I had Covid june/july last year. While I had symptoms id test myself most days with lateral flow tests to see when the viral load was on the decline. Out of curiosity I thought to attempt to test breath condensate. Using clean glass I collected samples from normal and heavy breathing, swabbing and testing the condensate yielded negative results despite me still testing strongly positive using the normal procedure.
Any ideas as how meaningful this result is? Ive read papers that suggest either way that covid is/isn't in tidal breath.
The lateral-flow tests are not sensitive enough to detect COVID in exhaled fog or droplets. But if you breathe enough of those droplets in, you will likely get infected.
My wife contracted Omicron a week or two ago, and I soon developed it as well, even though we are both fully vaccinated and boosted.
I administered the BinaxNow lateral-flow test to my wife, who had a scratchy cough and needed lots more sleep than normal, and she was strongly positive. (I didn't test myself on the assumption that I already know the answer - I had developed the same cough and sleep demand.)
In this test, one scrubs the inside of both nostrils up to 3/4" (19mm) in with a swab, collecting whatever is right on the mucosal skin that lines the nostril, and becomes a home for COVID. This is far more direct than sampling the droplets emitted while speaking. The scrubbing doesn't really hurt, but is maddeningly ticklish.
She probably got it from her immediate family, many of whom came down with Omicron as well. (There was a lot of travel because there was a death in the family.) In the immediate family, all are vaccinated and none of these infections were serious, none requiring medical attention.