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Human immunodeficiency virus (HIV) is a single-stranded RNA retrovirus that attacks and destroys CD4 cells1. CD4 receptors are found on the surface of T-helper lymphocytes, monocytes, macrophages, dendritic cells, and brain microglia. There are two types of HIV, type 1 and type 2. Type 2 is more virulent and primarily found in South Africa. In the United States, HIV-1 is more prevalent and will be the main focus of this section.


HIV is transmitted through three primary modes, sexual, parenteral, and perinatal. Perinatal mode of transmission can occur from a mother to her baby during pregnancy, at birth, or through breastfeeding1. The virus can be found in and transmitted through blood, semen, preseminal fluid, rectal fluid, vaginal fluid, and breast milk. HIV transmission is facilitated with the presence of mucosa break and damaged tissue during sexual intercourse.


Voluntary HIV testing is recommended for patients aged 13-64 years in all healthcare settings where they are at high risk of transmission or exposure1,2. Pregnant women, patients who begin treatment for tuberculosis and/or sexual transmitted diseases, patients who present signs and symptoms of acute or chronic infections, and those who engage in high risk behaviors (i.e. unprotected sex, needle sharing, contaminated fluid exposure) should be tested for HIV annually. An acute or primary HIV infection may occur 4-6 weeks after exposure to HIV. The clinical presentation at this stage includes non-specific flu-like symptoms, such as fever, fatigue, myalgias, lymphadenopathy, gastrointestinal issues, night sweat, and maculopapular rash.


The CDC recommends the screening algorithm for the initial HIV screening using the combination immunoassay test of HIV antigen and HIV antibody1,2,3. Initial HIV tests may use blood or oral fluid. This test detects both HIV antibody and HIV p24 antigen as soon as 3-week and 2- week post exposure, respectively. If the initial test is positive, a confirmatory screening with HIV-1 and HIV-2 antibody differentiation is required to determine if patients have HIV-1 or HIV- 2. HIV diagnosis is confirmed when both the HIV antigen/antibody combination immunoassay and confirmatory screening are positive. The third nucleic acid test (NAT) is only conducted if the first test is positive but the second test is negative or indeterminate.

Patients can get over-the-counter (OTC) HIV test kits and perform at home. Currently, there are two FDA-approved tests available on market, the Home Access HIV-1 Test System and the OraQuick In-Home HIV Test. The OraQuick In-Home HIV Test provides rapid results as quick as 20 minutes. If tested positive in either one of these OTC HIV tests, the individuals must have a confirmatory test done at a healthcare clinic or healthcare provider's office. Both OTC tests detect HIV antibodies, which can take up to 6 months to develop. However, ...

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