Why do single partners get syphilis?

To put it bluntly, if the hygiene is not in place, you may encounter germs left by others when you go to the public toilet in the hotel, and then wash your hands when you touch your own parts, which is easy to be infected. Try not to touch public doorknobs, toilets, etc. When you go to the bathroom. Also, the source of infection may be your sexual partner, whose constitution is different from yours, and your antibody is not as good as hers, so it is easy to be infected. I hope so, dispel your doubts and get points!