What two groups of body liquids, through physical, sexual intimacy, must mix in order to contract STI's?

The two groups of bodily fluids through physical or sexual intimacy that must mix in order to contact sexually transmitted infection (STI) are blood and semen or vaginal fluids. Even though our bodily fluids keep our bodies healthy, it can still cause this infection because it is passed on through unprotected sexual activities, contact with infected skin, and sharing needles for drug use, tattoos and ear piercing.

There are many kinds of STIs that are either treatable and curable or treatable but not curable such as: chlamydia, gonorrhea, genital herpes, genital warts, syphilis, human immunodeficiency virus (HIV), acquired immune deficiency syndrome (AIDS), hepatitis A, hepatitis B and hepatitis C. The cases of people living with STIs are on the rise, this is why it is recommended to practice safe sex, limit the number you have sex with, and get tested as soon as possible.