Get the facts on Human Immunodeficiency Virus (HIV) & Acquired Immunodeficiency Syndrome (AIDS) with this 100%-accurate animated video. Part of Focus Apps' Understanding Disease: Infectious Diseases & Oncology series, the HIV & AIDS app demonstrates the structure of these viruses, pathogenesis, and immune response. HIV causes AIDS, a condition in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive. The virus can be found in circulating blood lymphocytes, plasma, semen, and body fluids and in all the tissues of the body. They destroy the T4 helper cells that are vital for immune responses to pathogens, bringing about a vulnerability to diseases in the patient. Explore clinical features, manifestation, test for monitoring infection, and treatment.