[The measles paradox explained: how measles virus both suppresses and activates the immune system].

Measles virus infection causes immune suppression, resulting in increased susceptibility to opportunistic infectious diseases. At the same time, the infection induces a strong virus-specific immune response, resulting in lifelong protection against measles. Based on studies in tissue cultures, laboratory animals and patients, we have unravelled the mechanism by which measles affects the immune system, thereby explaining the 'measles paradox'. Recent studies based on blood samples of unvaccinated children in the Orthodox Protestant community collected before, during and after measles have provided further evidence of this mechanism. Results show that measles causes 'immune amnesia'. This article summarizes the results of these studies from a clinical perspective.