We were in NOLA the week before (cooking class, mostly). We'd been tracking C19 as an overseas thing that might come here - and was probably communicated through touch (fomites). We brought sanitizing wipes, sanitized all hard surfaces around us, after apologizing to seat neighbors. We were around for some of the pre-Mardi Gras parades and street parties. I'd never seen a street so crowded with people, mostly avoided that as I'm a bit crowd averse.

From what I found out just afterwards, C19 hit the krewes (parade people) pretty hard. Could easily have been us. We were both over 65 (but fit, no additional risk factors).