Which virus is the causative agent of AIDS?

Which virus is the causative agent of AIDS?

• A. Cytomegalovirus
• B. Epstein-Barr virus
• C. Hepatitis B virus
• D. Human immunodeficiency virus

Answer: (D)

HIV is the virus that causes AIDS. It specifically infects and destroys CD4+ T helper cells, leading to progressive immune system failure. When CD4 counts drop to very low levels or when AIDS-defining opportunistic infections or cancers appear, the condition is diagnosed as AIDS. The other viruses listed can cause disease in people with weakened immunity, including those with AIDS, but they do not themselves initiate the syndrome. HIV is a retrovirus with an RNA genome that integrates into the host genome, establishing a persistent infection.

HIV is the virus that causes AIDS. It specifically infects and destroys CD4+ T helper cells, leading to progressive immune system failure. When CD4 counts drop to very low levels or when AIDS-defining opportunistic infections or cancers appear, the condition is diagnosed as AIDS. The other viruses listed can cause disease in people with weakened immunity, including those with AIDS, but they do not themselves initiate the syndrome. HIV is a retrovirus with an RNA genome that integrates into the host genome, establishing a persistent infection.