Which of the following describes passive immunity?

Passive immunity refers to the protection from infectious diseases that is achieved when antibodies are transferred from one individual to another. This type of immunity is not created within the individual's own immune system but rather obtained from an external source.

In the context of the correct answer, passive immunity is indeed present from birth and inherited from the mother. During pregnancy, a mother passes antibodies to her unborn child through the placenta. These antibodies provide the newborn with immediate protection against certain infectious agents. Additionally, infants continue to receive passive immunity through breast milk, particularly through colostrum, which is rich in antibodies.

This contrasts with other forms of immunity; for instance, active immunity develops when an individual is exposed to a pathogen and their immune system mounting a response by creating its own antibodies, either through an actual infection or vaccination. Since passive immunity does not involve the individual's own immune response, it is temporary, typically lasting only a few weeks to a few months after birth.

Understanding passive immunity is crucial for dental nurses and other healthcare professionals, as it highlights the importance of maternal health and nutrition during pregnancy to ensure that infants receive adequate protection against infections during their earliest days when their own immune systems are still developing.