PCR can detect pathogens in immunodeficient animals.

• A. True
• B. False
• C. Only when the animals have fully functioning immune systems
• D. Not applicable

Answer: (A)

PCR detects the genetic material of a pathogen, not the animal’s immune response. Because it looks for DNA or RNA from the pathogen itself, immunodeficient animals can still be tested effectively—their immune status doesn’t prevent the assay from finding the pathogen if its nucleic acids are present. In fact, infections in immunocompromised hosts can sometimes yield higher pathogen levels, which can make detection even more straightforward, though highly sensitive assays can detect very small amounts when sample quality and handling are good. Proper sample collection and avoidance of inhibitors or contamination are important to get reliable results. So the statement is true. It isn’t restricted to animals with fully functioning immune systems, and saying it’s not applicable would miss how PCR works.