Vaccinating most of a population can provide fringe benefits for all. Why do your neighbor's vaccinations help make you safer from infection? SA's Dina Fine Maron takes a look at the concept of "herd immunity" and how it helps keep outbreaks at bay.
More to explore:
Community Immunity (NIAID)
http://www.niaid.nih.gov/topics/pages/communityimmunity.aspx
Concepts of Herd Protection & Immunity [Pdf] (WHO) http://www.who.int/vaccine_research/documents/WHE_Smith_presentation.pdf
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