HIV can be transmitted sexually, mainly because the amount of HIV in the secretions of the patient’s reproductive tract can be very high. According to relevant data, the amount of HIV in semen can reach more than 1 million or even close to 10 million in 1 ml, so it is very high. In women, the amount of HIV in vaginal secretions is a little smaller, but the amount is still very high. Therefore, if such a high content of genital secretions comes into contact with the mucous membrane of the other party, there is a possibility of transmission, and if it comes into contact with a broken wound of the other party, of course, it is more likely to lead to transmission. Therefore, if the sexual activity only touches the mucous membrane of the genital tract and does not break, the possibility of infection is relatively not so great. However, if transrectal sex occurs and contact is made with a broken wound, the likelihood of transmission increases.