A small jab - a big effect: nonspecific immunomodulation by vaccines

Trends Immunol. 2013 Sep;34(9):431-9. doi: 10.1016/j.it.2013.04.004. Epub 2013 May 14.


Recent epidemiological studies have shown that, in addition to disease-specific effects, vaccines against infectious diseases have nonspecific effects on the ability of the immune system to handle other pathogens. For instance, in randomized trials tuberculosis and measles vaccines are associated with a substantial reduction in overall child mortality, which cannot be explained by prevention of the target disease. New research suggests that the nonspecific effects of vaccines are related to cross-reactivity of the adaptive immune system with unrelated pathogens, and to training of the innate immune system through epigenetic reprogramming. Hence, epidemiological findings are backed by immunological data. This generates a new understanding of the immune system and about how it can be modulated by vaccines to impact the general resistance to disease.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Animals
  • Communicable Disease Control / methods*
  • Communicable Diseases / immunology*
  • Humans
  • Immune System / immunology*
  • Vaccines / adverse effects
  • Vaccines / immunology*


  • Vaccines