The human immunodeficiency virus (HIV) is considered the causative agent of AIDS, and it is a virus that belongs to the family of retroviruses (Retrovirus). When the virus enters the body, it targets immune cells known as CD4 (T-cells – a type of white blood cell essential for immune defense). Throughout several stages — which differ depending on whether diagnosis and treatment occur or not — the virus replicates inside these cells and destroys them, leading gradually to a severe weakening of the immune system. The period preceding the appearance of clear symptoms may extend for months or years, as in the first stage of infection the affected person may experience symptoms similar to a mild flu: fever, headache, skin rash, sore throat — or no signs may appear at all. With the progression of the infection and the spread of the virus inside the body without treatment, the immunity of the affected person starts to weaken significantly, the ability to resist infections becomes at risk, and “opportunistic” diseases emerge (infections caused by microbes or fungi that usually do not affect healthy individuals). Types of cancer may also arise (such as Kaposi sarcoma and lymphomas), along with other serious complications. HIV is transmitted through body fluids: blood, semen, vaginal secretions, and breast milk. The most common modes of transmission include unprotected sexual intercourse (vaginal or anal) with an infected person, sharing needles or unsterilized instruments (as in injection drug use), receiving blood or blood products that have not been properly screened, and mother-to-child transmission during pregnancy, childbirth, or breastfeeding if preventive measures are not taken. In contrast, the virus does not spread through handshakes, hugging, sharing food/drinks, or ordinary social contact — thus, the social stigma surrounding infected individuals is often based on incorrect information. Although AIDS has no complete cure so far, antiretroviral therapy (ART) has produced a transformative change in the course of the disease: the infection has become a manageable chronic condition, allowing a long and healthy life for those who receive treatment regularly. When an infected person takes ART consistently, the amount of virus in the blood decreases to undetectable levels, which reduces the chances of transmitting the virus to others and significantly improves quality of life. In terms of prevention, the use of protective measures such as condoms during sexual activity is advised, along with avoiding the sharing of needles or tools that can transmit blood. Early testing and verification of health status are also very important, because many people may carry the virus without knowing it, which may lead to unmonitored spread. On the global scale, by the end of 2024, there were about 40.8 million people living with HIV. In the same year, approximately 1.3 million new infections were recorded, and 630,000 deaths occurred due to AIDS-related diseases. However, expanded access to treatment contributed greatly to improving the situation: among individuals living with HIV, about 77% were receiving antiretroviral therapy in 2024. But despite the progress, the challenge remains great because the virus does not completely disappear from the body, and unless efforts in prevention, diagnosis, treatment, education, and awareness continue, the risk of spreading the infection and the ongoing suffering of affected individuals will persist. The battle against AIDS today is not only with a virus — but also with ignorance, social stigma, poverty, and limited access to healthcare services. Therefore, accurate knowledge, early testing, adherence to treatment, and providing a supportive environment for patients are the essential tools to fight this epidemic.