Considering that they are calling the flu a bacteria when its a virus its kind of unlikely and if the flu was found on the onions that because its airborne and will settle on anything so you know had they tested the table cloth it would have been positive too. Are they antimicrobial yeah I'm not going to look it up but if you can store it at room temp its probably got something that inhibits bacterial growth. Regarding potato salad it is totally the worst if you leave it out more than a couple of hours I would personally blame the potatoes for that because they are a great carb source normally protected by their skin----they are in fact so great at growing bacteria that in the olden days people used potato slices instead of agar plates. There is even a type of potato agar used today. In short they took a few things that might be fact and mixed them with a lot of bs leading to a poor conclusion.