Which statement about opportunistic pathogen infection in AIDS is true?

• A. Individuals with AIDS are less likely to develop opportunistic infections than healthy individuals.
• B. Opportunistic infections in AIDS patients are always caused by viruses.
• C. Opportunistic pathogens only infect people with fully functional immune systems.
• D. Opportunistic infections are more common in individuals with AIDS due to weakened immune defenses.

Answer: (D)

Verified step by step guidance

1. Understand the concept of an opportunistic pathogen: these are microorganisms that normally do not cause disease in a healthy host but can cause infections when the host's immune system is compromised.
2. Recognize that AIDS (Acquired Immunodeficiency Syndrome) severely weakens the immune system, particularly by reducing the number of CD4+ T cells, which are crucial for immune defense.
3. Analyze each statement in the problem by comparing it to the known effects of AIDS on the immune system and the nature of opportunistic infections.
4. Recall that individuals with AIDS have weakened immune defenses, making them more susceptible to opportunistic infections, which can be caused by bacteria, fungi, viruses, or protozoa—not just viruses.
5. Conclude that the true statement is the one indicating that opportunistic infections are more common in individuals with AIDS due to their weakened immune defenses.