API stands for Application Programming Interface, i.e. API is the way for an application to interact with certain system/application/library/etc. For example, there are API's for OS (WinAPI), API's for other applications (like databases) and for specific libraries (for example, image processing), etc.
Acute HIV infection: The first stage of HIV, known as the primary or acute infection, may cause symptoms of fever and skin rash. This is because the virus is multiplying rapidly in the body and infecting immune cells. This phase generally lasts several weeks.
HIV infection is caused by the human immunodeficiency virus. You can get HIV from contact with infected blood, semen, or vaginal fluids. 1  Most people get the virus by having unprotected sex with someone who has HIV.  Another common way of getting it is by sharing drug needles with someone who is infected with HIV.