"The HIV pandemic continues to be a worldwide public-health problem. The virus, which is spread through sexual contact, exposure to infected blood, or through shared syringes, is highly infective, rapidly mutates, and has no cure. Because there is no effective vaccine or other prophylaxis available, the current best practice and standard of care for those infected is an early, accurate diagnosis for the presence of HIV followed by immediate treatment on antiretroviral therapies and counseling. The most commonly used and widely accessible diagnostic tests and assays rely on the presence of HIV antibodies, but the window period before seroconversion takes place to produce these antibodies in the host can take up to six months. Moreover, newborns cannot be tested with these methods due to maternal antibodies masking their true HIV status. Thus, antibody-detecting approaches have major shortcomings in incidence and infant testing, which are critical components to early treatment and reduced transmission rates. Diagnostic tests targeting antibodies or nucleic acids are also susceptible to false or discordant results due to viral variations.Hence, of particular interest as a target then is the conserved viral capsid protein, p24 antigen. Under certain conditions, antigen assays can achieve sensitivities that nearly match those of NATs without the need for amplification steps, and the antigen has a much shorter window period than the antibody, allowing it to be much more effective at incidence and infant testing."