It would be hard to document such cases, when public nudity has been restricted for thousands of years.

You should not have to stretch your imagination, however, to figure out all the possible transmission vectors.

Clean nudity is inferior to clean clothing, that's OK.

However, we allow fully clothed homeless that haven't bathed in months, or even anybody with poor personal hygiene. We allow dirty street, dirty buses and public transports, kids playing in sewers in bad area of town, hoarders and countless other documented hygiene threats.

So let's be intellectually honest and accept that nakedness is a morality issue first and foremost.