Sexual intercourse with sex workers is always dangerous. Effectiveness of a condom against sexually transmitted diseases depends on its quality and usage. Safety can be at high risk due to poor condom usage. However, condoms do not provide complete protection from all sexually transmitted diseases. Chancroid can occur in genital areas those are protected by condom. During sexual intercourse chancroid can easily transmit through skin-to-skin contact. Kissing of lips to lips is easy way to transmit infections of the mouth, throat, respiratory tract and eyes. The reality is that mouth-to-mouth contact is an efficient way to spread diseases. Oral herpes is caused by a viral infection. The virus is called Herpes Simplex and infections may occur once or return again and again. Herpes can be a recurring and upsetting disease. Sucking the vagina of sex worker in also dangerous. That can transfer fatal infection, if her vagina in infected. If the breast belongs to a sex worker who is lactating, STDs can be spread through breast milk.