Bacteria are something the masks most folks use will readily block. Viruses, being about one-twentieth the size of many bacteria, will pass through those masks. The manufacturers of the masks understand this which is why they include warning labels on their boxes of masks, the warning usually being something along the lines of:
These masks help protect against certain particulate contaminants but do not eliminate exposure to the risk of any disease or infection. (Emphasis mine – ed.)As best I know only N95 facemasks are capable of filtering out viruses. This is the type used by medical personnel. This is not the type used by most people.
The mask mandates are really more of a psychological action to make people feel better, not a means of actually preventing the spread of Covid-19. How long will it take before people realize most masks really don’t work? They aren’t designed to filter out viruses and never were.