Question

Why do opportunistic diseases develop in an individual with AIDS?

1) They are side effects of drug treatment of AIDS
2) They are sexually transmitted to individuals during exposure to HIV
3) They are characteristics in individuals with stimulated B and T lymphocytes
4) These infections or tumors occur in a person with an incompetent immune system

Answer 1

Opportunistic diseases develop in individuals with AIDS due to a severely compromised immune system, resulting from the destruction of CD4 T-cells by HIV. These diseases exploit the weakened defenses to cause infections and tumors that are fatal for the patient.

Step-by-step explanation:

The opportunistic diseases develop in an individual with AIDS primarily because of an incompetent immune system. AIDS, caused by the Human Immunodeficiency Virus (HIV), leads to a significant reduction in CD4 T-cells, which are crucial for the immune system to function properly. As the T-cell count falls, the body becomes increasingly vulnerable to infections and tumors that a healthy immune system would normally fend off.

These infections, known as opportunistic because they take advantage of the weakened immune system, are generally rare in individuals without immunodeficiency. Common opportunistic diseases associated with AIDS include pneumocystis pneumonia, esophageal candidiasis, Kaposi's sarcoma, and Burkitt's lymphoma. The opportunistic infections and cancers often become the direct cause of death in individuals with AIDS.