Which virus damages the immune system?

• A. Hepatitis C virus
• B. Herpes simplex virus
• C. Human immunodeficiency virus (HIV)
• D. Influenza virus

Answer: (C)

HIV damages the immune system by targeting CD4+ T helper cells, which are essential for coordinating immune responses. By infecting and progressively destroying these cells, HIV weakens the body's ability to fight infections and cancers. Over time, this leads to AIDS, where opportunistic infections appear and the immune system is severely compromised. The other viruses don’t cause this sustained immune destruction: Hepatitis C mainly harms the liver, Herpes simplex establishes latent infections in nerves with periodic reactivations, and Influenza causes an acute illness but doesn’t erode immune function long-term. So the virus that damages the immune system is HIV.