The virus cant survive if it is just in the air. People can only be infected by the exchange of body fluids. The fluids that are exchanged are fluids such as, semen, vaginal urine, blood, and human milk. (Meyer)
The virus is most common when you have sex, when semen or the vaginal fluids are exchanged. (Meyer)
You can get HIV also by sharing any needles when doing drugs, and if a mother has HIV , and breast feeds her child, then the child is likely to get the virus too.
The first stage of the symptom is flu like feelings.
What I know about STDs is that you can have different symptoms. For example in some diseases you can get the diseases from skin to skin contact, blood, or just from kissing. The STD that I have is HIV and AIDS. What I know about HIV is that you can prevent it from having sex. If you do have sex with your partner, than you should have protection, so you cannot get what your partner has. Before you do any of this, you should also go get checked, just to make sure you don’t have the disease.