- HIV (human immunodeficiency virus) was first discovered in 1981 in homosexual men.
- HIV is a virus that leads to acquired immunodeficiency syndrome (AIDS).
- HIV is transmitted through body fluids such as blood, semen/vaginal fluids, rectal fluids, and breast milk.
- In the United States, HIV is most often transmitted through sexual intercourse and needle sharing.
- Though the rate of new HIV infections has declined over the past decade, 1 in 7 individuals do not know they are infected.
- In 2015, HIV was found to be the ninth leading cause of death in the 25 to 34 years and 35 to 44 years age groups.
- Currently, 1.1 million people in the United States are living with HIV/AIDS.
- Worldwide, there are 36.7 million (2.1 million younger than age 15 years) people living with HIV/AIDS.
- Homosexual and bisexual men are the more affected, with young African American gay men being the most affected.
- Since the start of the epidemic, more than 35.0 million individuals have died of AIDS-related illnesses, with 1 million in 2016 alone.
- Zidovudine (AZT) was the first drug approved for the treatment of HIV in 1987; today, 49 single or combination drugs are approved.
- The acute stage may present with flu-like illness: general fatigue, diarrhea, nausea/vomiting, generalized rash, myalgia, fever, dysphagia
- Can be asymptomatic in the initial stage for up to 10 years
- Later symptoms and signs may include muscle wasting/atrophy, weight loss, and signs relating to opportunistic infections
- Diagnosis is made by assessing either the HIV antigens, antibodies, or the actual viral load in the blood.
- A fourth-generation HIV enzyme-linked immunosorbent assay (ELISA) that detects both the HIV antigen and antibody was approved in 2011. The fourth-generation test may allow for faster diagnosis since it assesses HIV antigen and antibody as little as 2 weeks and up to 6 weeks after infection.
- The Centers for Disease Control and Prevention (CDC) and US Food and Drug Administration (FDA) recommends fourth-generation screening; the US Preventive Services Task Force (USPSTF) recommends ELISA and confirmatory Western Blot.
- Viral load is performed to determine the amount of virus in the bloodstream; it is also used to monitor treatment once initiated. An undetectable viral load is considered <20 copies/cells.
- CD4 (T-cell lymphocyte) count indicates how well the immune system is working; those infected with HIV typically have CD4 counts <500 cells/mm3
- Phenotype and genotype testing can be performed to measure drug resistance prior to initiating HIV therapy or if there is suspicion of resistance while taking medications.