Ryan S. answered • 03/05/20
Medical Doctor
Human Immunodeficiency Virus (HIV) is the virus that causes Acquired Immunodeficiency Syndrome (AIDS). Essentially it is a virus that attacks and destroys the White Blood Cells (WBCs) that are responsible for fighting pathogens (e.g. bacteria, viruses, fungi). When enough of your WBCs have been destroyed, the condition officially becomes AIDS. People with AIDS are vulnerable to pathogens that healthy people normally don't get sick from. These are known as opportunistic infections and include things like P. jirovecii, Candida, and Tuberculosis to name a few.
So, HIV is the virus that causes the infection and AIDS is the condition of being vulnerable to other infections.
Symptoms of initial infection with HIV generally resemble the flu – fever/chills, fatigue, nausea, vomiting, diarrhea. Not every infected person will experience this, and if they do, it may be mild. Diagnosis of HIV is done with laboratory testing (ELISA screening and confirmed with Western Blot). Diagnosis of AIDS = HIV positive + evidence of an opportunistic infection. This generally happens when when the CD4+ type of WBCs drops below 200.
Standard treatment typically involves a combination of 3 anti-retroviral medications. They are designed to stop HIV from spreading by a few different mechanisms, which increases the likelihood that they will be effective. Additionally, when there are less than 200 CD4+ type WBCs patients are provided additional antibiotics, such as TMP-SMX, to take as prophylaxis (meaning they take it to prevent illness when they are not actively sick).
