If someone has HIV positive why are they more likely to get infections?

Individuals with HIV (Human Immunodeficiency Virus) are more susceptible to infections due to the virus's impact on the immune system. HIV primarily targets and destroys CD4+ T cells, which play a crucial role in the body's immune response. Here's how HIV infection increases the risk of infections:

1. Weakened Immune System:

- HIV selectively targets and infects CD4+ T cells, also known as helper T cells. These cells are essential for coordinating the immune system's response to infections. As the number of CD4+ T cells decreases, the body becomes less effective in fighting off pathogens.

2. Reduced T Cell Function:

- Even uninfected CD4+ T cells in individuals with HIV may have impaired functionality. This means that even if some CD4+ T cells are present, their ability to recognize and respond to infections may be compromised.

3. Increased Viral Replication:

- HIV infection leads to ongoing replication of the virus within the body. This process can further damage immune cells and tissues, making it harder for the body to mount an effective immune response.

4. Opportunistic Infections:

- Due to the weakened immune system, individuals with HIV are more vulnerable to a variety of opportunistic infections that rarely cause illness in people with healthy immune systems. These infections can include:

- Bacterial infections like tuberculosis and pneumonia

- Fungal infections like cryptococcal meningitis

- Parasitic infections like toxoplasmosis

- Viral infections like cytomegalovirus (CMV) and Kaposi's sarcoma-associated herpesvirus (KSHV)

- Certain cancers, such as Kaposi's sarcoma and non-Hodgkin lymphoma

5. Reactivation of Latent Infections:

- HIV infection can also reactivate latent infections that may have been dormant in the body. For example, people with HIV are more likely to develop active tuberculosis if they were previously exposed to the tuberculosis bacteria.

6. Mucosal Barrier Damage:

- HIV can damage mucosal barriers, such as those in the gut and respiratory tract. These barriers normally prevent the entry of pathogens into the body. Damage to these barriers can increase the risk of infections.

7. Compromised Antibody Production:

- In addition to affecting T cells, HIV can impair the production of antibodies by B cells. Antibodies are proteins that help the body recognize and neutralize specific pathogens. Reduced antibody production further weakens the immune response.

It is important to note that advancements in HIV treatment, particularly antiretroviral therapy (ART), have significantly reduced the risk of infections and improved the overall health of individuals living with HIV. With effective management of the viral load, many opportunistic infections can be prevented, and the immune system can be strengthened, leading to improved overall health and longevity for people with HIV.