Thanks for the question. I must tell you that there are blood tests which usually detect most of the STIs in human beings. You can also go for Pap test. It is done within the period of three years after having the intercourse. These tests can detect the HPV which in turn are 40 in number. It also reveals whether a person has genital warts or not. There are also some STIs which do not show any kind of symptoms for years and hence one does not get to know about them before it is too late. Coming to the second of yours which is about genital warts; as mentioned it is one of the many sexually transmitted disease which is transmitted by one of the many sexually transmitted infections. It is highly dangerous disease as you have seen in the Genital warts pictures. In this the affected person develops many warts which are small in size near his or her genital areas. These warts are the result of sexual intercourse with an already infected person. If one is not using a condom then the risk is higher. If one is not using any protection and considers that since he has no ejaculation he would not be affected by the disease. Then he is certainly wrong. Then also this disease can be transmitted to his body by close contact of the genitals. In case there is some sort of cut near the genitals then also it can b transmitted. Hence, it is advisable tat whenever you have sex with someone you ask that someone to wear protection in order to prevent yourself from genitals warts. Take care of yourself.