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Why can immunity after measles last for life?

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Health monitoring — human disease The routine monitoring of blood pressure levels is an important part of assessing an individual's health. Blood pressure provides information about the amount of blood in circulation and about heart function and thus is an important indicator of disease.

Immunity to measles can last for life due to the immune system's capacity for immunological memory.12

When the body is first exposed to the measles virus, the immune system undergoes a process called clonal selection, which produces both short-lived effector cells to fight the immediate infection and long-lasting memory cells. These memory cells remain in the body for years, or even a lifetime, "remembering" the specific antigen associated with the virus.12

If the individual is re-exposed to the measles virus later in life, these memory cells recognize the pathogen and trigger a rapid, effective secondary immune response. This swift reaction prevents the virus from causing a reinfection, effectively providing lifelong protection. This principle of immunological memory is also the foundation for vaccination, which safely alerts the immune system to an antigen to establish similar long-term protection.12345