How does HIV/AIDS affect the immune system?

HIV/AIDS weakens the immune system by destroying cells that fight disease and infection, particularly CD4 cells or T cells.

HIV, or Human Immunodeficiency Virus, is a type of virus that specifically targets the immune system of the host. It does this by infecting and destroying CD4 cells, also known as T cells, which are a type of white blood cell that plays a crucial role in the immune response. The destruction of these cells leaves the body vulnerable to a wide range of infections and diseases that it would normally be able to fight off.

The virus enters the body and attaches itself to a CD4 cell. It then fuses with the cell, releasing its RNA and enzymes into the host cell. The viral RNA is converted into DNA by an enzyme called reverse transcriptase. This viral DNA is then integrated into the host cell's DNA with the help of another enzyme called integrase. Once integrated, the viral DNA uses the host cell's machinery to produce new viral particles. These new viruses then leave the host cell, destroying it in the process, and go on to infect other CD4 cells.

As the number of CD4 cells decreases, the immune system becomes progressively weaker. This stage of the infection is known as Acquired Immunodeficiency Syndrome (AIDS). At this point, the body becomes susceptible to opportunistic infections and diseases, which are infections and diseases that take advantage of a weakened immune system. These can include certain types of cancer and infections caused by bacteria, viruses, fungi, and parasites.

The destruction of the immune system by HIV is a gradual process that can take many years. During this time, the person infected with the virus may not show any symptoms or feel sick. This is why regular testing for HIV is so important, as early detection and treatment can help to slow down the progression of the disease and improve the quality of life for those living with HIV/AIDS.