HIV remains one of the world’s most significant public health challenges. Both HIV-1 and HIV-2 viruses can elicit strong immune responses including the production of antiviral antibodies. Presence of specific anti-HIV-1 or HIV-2 virus antibodies circulating in the blood indicates the exposure of an individual to HIV-1 or HIV-2 which is of great value for clinical diagnosis. In addition, tests that detect HIV p24 antigen may be useful for the early diagnosis of HIV as p24 antigen is one of the earliest markers of HIV infection. It has been suggested that HIV infection is detectable with a p24 antigen test 6 days earlier than an antibody test.