If by spit you mean sneeze or cough, then yes. If you're potentially contagious, wearing a mask helps prevent you from spraying liquid droplets in the air and i

If by spit you mean sneeze or cough, then yes. If you're potentially contagious, wearing a mask helps prevent you from spraying liquid droplets in the air and infecting others. It's not perfect, but it's something. And any since any of us could be a carrier currently and there's no sufficient tests to find out, the best things we could do in order are 1) stay home and quarantine, 2) wear masks and sanitize our hands whenever we go out. Both for the sake of not catching it, and for the sake of not spreading it.