"So the disease is spread by spreading feces, not nudity per se, which is what i said. A clean nude person is not spreading feces simply by sitting."
Your anus and most of your crack is never free from fecal bacteria, unless you soak in bleach routinely, so sorry, I don't buy your argument.
"The argument from authority is NOT necessarily false. Or, if it is, then is everything you think about global warming, for example, false, because you only know what some authorities have said? Or are you personally a scholar on the matter? See what I mean?"
This is a mischaracterization of how we accept "credible" information. It is NOT derived from the authority, but from methodology, replicability, consensus of data, etc.