Which of the following is not a characteristic of passive immunity?

• A. Development of long-term memory
• B. Transfer of antibodies
• C. Occurs naturally or as a result of therapy
• D. Provision of immediate protection

Answer: (A)

Passive immunity gives you ready-made antibodies from someone else, so protection is immediate. But because the recipient’s own immune system isn’t being primed or activated, it doesn’t form memory cells. Memory is built when the body’s own immune response is triggered by exposure to an antigen, which happens in active immunity. That’s why the idea of developing long-term memory is not a feature of passive immunity, even though transferring antibodies, occurring naturally or via therapy, and providing immediate protection are all correct aspects of passive immunity.