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Vaccines can prevent outbreaks of disease and save lives.
When a critical portion of a community is immunized against a contagious disease, most members of the community are protected against that disease because there is little opportunity for an outbreak. Even those who are not eligible for certain vaccines—such as infants, pregnant women, or immunocompromised individuals—get some protection because the spread of contagious disease is contained. This is known as "community immunity."
The principle of community immunity applies to control of a variety of contagious diseases, including influenza, measles, mumps, rotavirus, and pneumococcal disease.
Last reviewed: January 2017
Last syndicated: May 11, 2017
This content is brought to you by: The National Institute of Allergy and Infectious Diseases (NIAID)