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In the case of persistence we show the existence of a stationary distribution and derive expressions for its mean and variance. The results are illustrated by computer simulations, including two examples based on real-life diseases.<\/jats:p>","DOI":"10.1137\/10081856x","type":"journal-article","created":{"date-parts":[[2011,6,3]],"date-time":"2011-06-03T14:32:00Z","timestamp":1307111520000},"page":"876-902","source":"Crossref","is-referenced-by-count":693,"title":["A Stochastic Differential Equation SIS Epidemic Model"],"prefix":"10.1137","volume":"71","author":[{"given":"A.","family":"Gray","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"D.","family":"Greenhalgh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"L.","family":"Hu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"X.","family":"Mao","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J.","family":"Pan","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"351","published-online":{"date-parts":[[2011,6,2]]},"reference":[{"key":"R1","unstructured":"E. 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