I"m pretty sure that being normal works the same way that zombies do. If a normal person bites you, then you instantly become normal too. We cannot test this theory since normal people don’t bite people.
it’s actually not transmitted through bites, but through normal social interaction, also known as “peer pressure.”
it is one of the most terrifying forms of zombiism, because they cannot transform you all the way, only various levels of surface assimilation. You end up acting just as zombified as them, but with your own brain aware and silently screaming on the inside.
it is unknown whether “true” normal people really exist.