HIV Infections.AIDS

Human Immunodeficiency Virus (HIV) and Acquired Immunodeficiency Syndrome (AIDS) constitute one of the most devastating infectious diseases in human history, posing a major global health, social, and economic burden since the early 1980s. HIV is a retrovirus that primarily attacks the human immune system, specifically the CD4+ T lymphocytes, macrophages, and dendritic cells, which play a critical role in coordinating immune responses. The progressive destruction of these immune cells leads to a decline in immune function, rendering the individual vulnerable to opportunistic infections, malignancies, and other complications that define the AIDS stage of the disease. HIV is transmitted primarily through unprotected sexual intercourse, Sharing of contaminated needles, transfusion of infected blood, and from mother to child during pregnancy, childbirth, or breastfeeding. The virus does not spread through casual contact, insect bites, or sharing food and water. Once inside the body, HIV undergoes a complex process of replication involving attachment, fusion, reverse transcription, integration, and viral assembly, ultimately resulting in immune system failure if untreated. The infection moves through three main stages: the "acute phase," which is characterized by symptoms resembling those of the flu; the "chronic (latent) phase," which may last for years with few symptoms; and the "AIDS stage," which is characterized by severe immune suppression and infections that pose a threat to one's life. Clinically, HIV infection presents with a wide spectrum of manifestations depending on the stage and degree of immune compromise. Preventing disease progression necessitates prompt diagnosis and initiation of antiretroviral treatment (ART). ELISA, Western blot, polymerase chain reaction (PCR), complete blood count (CBC), and CD4 count are all important laboratory tests that are used in diagnosis, monitoring, and treatment evaluation. The introduction of combination ART has transformed HIV infection from a fatal disease to a manageable chronic condition, significantly improving life expectancy and quality of life.