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Then, we discovered robust seasonal variation in query behavior, with a striking latitudinal gradient on a global scale. Next, we showed that real-time data-mining of queries could forecast the timing and magnitude of outbreaks. Finally, our analyses revealed that countries with government-mandated vaccination programs have significantly reduced seasonality of queries, indicating vaccination efforts mitigated chicken pox outbreaks.<\/jats:p>","DOI":"10.1073\/pnas.1523941113","type":"journal-article","created":{"date-parts":[[2016,5,31]],"date-time":"2016-05-31T23:18:41Z","timestamp":1464736721000},"page":"6689-6694","update-policy":"https:\/\/doi.org\/10.1073\/pnas.cm10313","source":"Crossref","is-referenced-by-count":85,"title":["Digital epidemiology reveals global childhood disease seasonality and the effects of immunization"],"prefix":"10.1073","volume":"113","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7084-9291","authenticated-orcid":false,"given":"Kevin M.","family":"Bakker","sequence":"first","affiliation":[{"name":"Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109;"},{"name":"Center for the Study of Complex Systems, University of Michigan, Ann Arbor, MI 48109;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9248-9450","authenticated-orcid":false,"given":"Micaela Elvira","family":"Martinez-Bakker","sequence":"additional","affiliation":[{"name":"Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6648-1463","authenticated-orcid":false,"given":"Barbara","family":"Helm","sequence":"additional","affiliation":[{"name":"Institute of Biodiversity, Animal Health, and Comparative Medicine, University of Glasgow, Glasgow G12 8QQ, United Kingdom;"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2644-9685","authenticated-orcid":false,"given":"Tyler J.","family":"Stevenson","sequence":"additional","affiliation":[{"name":"Institute for Biological and Environmental Sciences, University of Aberdeen, Aberdeen AB24 2TZ, United Kingdom"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"341","published-online":{"date-parts":[[2016,5,31]]},"reference":[{"key":"e_1_3_3_1_2","doi-asserted-by":"publisher","DOI":"10.1093\/oxfordjournals.aje.a121575"},{"key":"e_1_3_3_2_2","first-page":"4111","article-title":"Seasonality and comparative dynamics of six childhood infections in pre-vaccination Copenhagen","volume":"276","author":"Metcalf CJE","year":"2009","unstructured":"CJE Metcalf, ON Bjornstad, BT Grenfell, V Andreasen, Seasonality and comparative dynamics of six childhood infections in pre-vaccination Copenhagen. 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