immunological memory

Immunological memory is a key feature of the adaptive immune system, allowing the body to remember and respond more effectively to pathogens it has encountered before. This memory is established after an initial exposure to an antigen, such as from a disease or vaccination.12

During the primary immune response, specialized white blood cells called lymphocytes, specifically B cells and T cells, are activated. This activation leads to the production of effector cells that fight the current infection, and crucially, memory cells. These memory cells, both B and T cells, persist in the body for extended periods.13

Upon subsequent exposure to the same antigen, these memory cells rapidly mount a stronger and faster secondary immune response, often preventing illness altogether. This is why individuals who recover from certain diseases, like measles, are typically immune to reinfection.12