What is natural immunity characterized by?

Natural immunity is characterized by being present from birth and is often related to the genetic makeup of an individual. This type of immunity is inherent and exists without the need for prior exposure to specific pathogens or immunizations. Individuals are born with various defense mechanisms, such as physical barriers and immune system components, that offer some degree of protection against infections.

Although certain later-acquired immune responses can build upon natural immunity through exposure to pathogens, the defining feature of natural immunity is that it is part of an individual's biological makeup from birth. This distinguishes it from other forms of immunity, such as acquired immunity obtained through exposure to pathogens or through vaccination, which require prior interactions with specific agents to develop.