Answer:
There are three major causes of STDs/STIs:
Bacteria, including chlamydia, gonorrhea, and syphilis.
Viruses, including HIV/AIDS, herpes simplex virus, human papillomavirus, hepatitis B virus, cytomegalovirus (CMV), and Zika.
Parasites, such as trichomonas vaginalis, or insects such as crab lice or scabies mites.
Explanation: does that help?