One of the wsys to contact Sexually transmitted diseases (STD) is through casual or unprotected sexual intercourse or through the public toilet (especially water closet i.e WC).
One must be careful when using the water closet because when a person with an STD uses a water closet and another person comes in contact with the seat (porcelain bowl), there is a high possibility of the infection spreading. In the case of women, a wide surface area leaves chances for an even higher infection rate. Sexually transmitted diseases (STD) / sexually transmitted infections (STI) or venereal diseases (VD) manifest in the body of infected person in form of worms and other symptoms.
Sexually transmitted diseases are infectious diseases, which means that blood, and other body fluids that are coming from people with STD are highly contagious.