Prevalence in medicine is the number of [[disease]] cases (new and existing) within a population over a given time period.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#p</ref>
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'''Prevalence''' in medicine is the number of [[disease]] cases (new and existing) within a population over a given time period.<ref>http://www.cdc.gov/vaccines/about/terms/glossary.htm#p</ref>