This is true. Nail polish can be used on multiple clients using the same brush and no other hygiene requirements.
This is because nail polish is packed full of solvents (how it dries), so is not an environment that any pathogen can survive (possibly with the exception of a fungus as fungal spores can survive many environments).
However, even though this is true, it is not in the nail professionals’ remit to work on unhealthy nails.
