HIV/AIDS is a variable virus which means it changes often so there are many different strains of HIV/AIDS. These different strains belong to 2 types of HIV; HIV-1 and HIV-2.Type 1 is common in sub-Saharan Africa and the rest of the world. Type 2 is common in West Africa. Because there are so many different strains of HIV you must ALWAYS use a condom even if you are already HIV positive, this will prevent you from getting infected with a different strain, which could make you more sick.
Attribution: Straight Talk Foundation