{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,22]],"date-time":"2026-07-22T17:16:53Z","timestamp":1784740613680,"version":"3.55.0"},"reference-count":42,"publisher":"Wiley","issue":"1","license":[{"start":{"date-parts":[[2018,2,19]],"date-time":"2018-02-19T00:00:00Z","timestamp":1518998400000},"content-version":"vor","delay-in-days":49,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004423","name":"World Health Organization","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100004423","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Influenza Resp Viruses"],"published-print":{"date-parts":[[2018,1]]},"abstract":"<jats:sec><jats:title>Background<\/jats:title><jats:p>The aim of this study was to estimate excess pneumonia and influenza (P&amp;I) hospitalizations during influenza epidemics and measure their correlation with influenza vaccine coverage in the 65 and more years old, according to the type\/subtype of influenza virus.<\/jats:p><\/jats:sec><jats:sec><jats:title>Methods<\/jats:title><jats:p>The study period comprised week 40\/1998\u201040\/2015. Age\u2010specific weekly P&amp;I hospitalizations (<jats:styled-content style=\"fixed-case\">ICD<\/jats:styled-content>\u20109: 480\u2010487) as main diagnosis were extracted from the National Hospital Discharge database. Age\u2010specific baseline hospitalization rates were estimated by autoregressive integrated moving average (<jats:styled-content style=\"fixed-case\">ARIMA<\/jats:styled-content>) model without time periods with excess hospitalizations. Excess hospitalizations were calculated by subtracting expected hospitalization rates from the observed during influenza epidemic periods. Correlation between excess P&amp;I hospitalizations and influenza vaccine coverage in the elderly was measured with Pearson correlation coefficient.<\/jats:p><\/jats:sec><jats:sec><jats:title>Results<\/jats:title><jats:p>The average excess P&amp;I hospitalizations\/season was 19.4\/10<jats:sup>5<\/jats:sup> (range 0\u201046.1\/10<jats:sup>5<\/jats:sup>), and higher excess was observed in young children with &lt;2\u00a0years (79.8\/10<jats:sup>5<\/jats:sup>) and \u226565\u00a0years (68.3\/10<jats:sup>5<\/jats:sup>). In epidemics with A(H3) dominant, the highest excess hospitalizations were observed among 65 and over. Seasons which influenza B or A(H1)pdm09 dominance the highest excess was observed in children with &lt;2\u00a0years. High negative correlation was estimated between excess hospitalizations associated with A(H3) circulation and vaccine coverage in the elderly (<jats:italic>r<\/jats:italic>\u00a0=\u00a0\u2212.653; 95% CI: \u22120.950 to \u22120.137).<\/jats:p><\/jats:sec><jats:sec><jats:title>Conclusion<\/jats:title><jats:p>Over 80% of the influenza epidemics were associated with excess hospitalizations. However, excess P&amp;I hospitalizations pattern differed from age group and circulating virus. This ecologic approach also identified a reduction in excess P&amp;I associated with A(H3) circulation with increasing vaccine coverage in the elderly.<\/jats:p><\/jats:sec>","DOI":"10.1111\/irv.12501","type":"journal-article","created":{"date-parts":[[2018,2,22]],"date-time":"2018-02-22T16:06:11Z","timestamp":1519315571000},"page":"153-160","source":"Crossref","is-referenced-by-count":25,"title":["Excess pneumonia and influenza hospitalizations associated with influenza epidemics in Portugal from season 1998\/1999 to 2014\/2015"],"prefix":"10.1111","volume":"12","author":[{"given":"Emanuel","family":"Rodrigues","sequence":"first","affiliation":[{"name":"Departamento de Epidemiologia Instituto Nacional de Sa\u00fade Dr. Ricardo Jorge  Lisboa Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1849-1499","authenticated-orcid":false,"given":"Ausenda","family":"Machado","sequence":"additional","affiliation":[{"name":"Departamento de Epidemiologia Instituto Nacional de Sa\u00fade Dr. Ricardo Jorge  Lisboa Portugal"},{"name":"Escola Nacional de Sa\u00fade P\u00fablica Universidade NOVA de Lisboa  Lisboa Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Susana","family":"Silva","sequence":"additional","affiliation":[{"name":"Departamento de Epidemiologia Instituto Nacional de Sa\u00fade Dr. Ricardo Jorge  Lisboa Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6230-7209","authenticated-orcid":false,"given":"Baltazar","family":"Nunes","sequence":"additional","affiliation":[{"name":"Departamento de Epidemiologia Instituto Nacional de Sa\u00fade Dr. Ricardo Jorge  Lisboa Portugal"},{"name":"Escola Nacional de Sa\u00fade P\u00fablica Universidade NOVA de Lisboa  Lisboa Portugal"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2018,2,19]]},"reference":[{"key":"e_1_2_6_2_1","first-page":"8","article-title":"Trends in pneumonia mortality rates","volume":"22","author":"Wuerth BA","year":"2016","journal-title":"Emerg Infect Dis"},{"key":"e_1_2_6_3_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.amepre.2015.09.028"},{"key":"e_1_2_6_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2015.06.080"},{"key":"e_1_2_6_5_1","doi-asserted-by":"publisher","DOI":"10.2307\/4591848"},{"key":"e_1_2_6_6_1","doi-asserted-by":"publisher","DOI":"10.1001\/jama.292.11.1333"},{"key":"e_1_2_6_7_1","doi-asserted-by":"publisher","DOI":"10.1111\/irv.12292"},{"key":"e_1_2_6_8_1","first-page":"15","article-title":"Pneumonia and influenza hospitalizations among children under 5\u00a0years of age in Suzhou, China, 2005\u20102011","volume":"2016","author":"Zhang X","year":"2016","journal-title":"Influenza Other Respir Viruses"},{"key":"e_1_2_6_9_1","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pone.0020661"},{"key":"e_1_2_6_10_1","doi-asserted-by":"crossref","first-page":"331","DOI":"10.1177\/0962280209340201","article-title":"Time series methods for obtaining excess mortality attributable to influenza epidemics","volume":"20","author":"Nunes B","year":"2011","journal-title":"Stat Methods Med Res"},{"key":"e_1_2_6_11_1","doi-asserted-by":"publisher","DOI":"10.1111\/j.1750-2659.2009.00073.x"},{"key":"e_1_2_6_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2006.09.041"},{"key":"e_1_2_6_13_1","doi-asserted-by":"publisher","DOI":"10.2105\/AJPH.2009.168245"},{"key":"e_1_2_6_14_1","first-page":"18","article-title":"Early estimates of the excess mortality associated with the 2008\u20109 influenza season in Portugal","volume":"14","author":"Nogueira PJJ","year":"2009","journal-title":"Euro Surveill"},{"key":"e_1_2_6_15_1","first-page":"461","article-title":"Vaccines against influenza WHO position paper \u2010 November 2012","volume":"87","author":"World Health Organization","year":"2012","journal-title":"Wkly Epidemiol Rec"},{"key":"e_1_2_6_16_1","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa070844"},{"key":"e_1_2_6_17_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.vaccine.2008.07.048"},{"key":"e_1_2_6_18_1","doi-asserted-by":"publisher","DOI":"10.1016\/S1473-3099(11)70295-X"},{"key":"e_1_2_6_19_1","doi-asserted-by":"crossref","first-page":"486","DOI":"10.1016\/j.vaccine.2015.12.003","article-title":"Trends in U.S. hospitalizations and inpatient deaths from pneumonia and influenza, 1996\u20102011","volume":"34","author":"Chang DH","year":"2016","journal-title":"Vaccine"},{"key":"e_1_2_6_20_1","first-page":"E070517","article-title":"Influenza vaccine coverage and the attack rate of influenza\u2010like illness among the elderly in Portugal: is there a correlation?","volume":"12","author":"Nunes B","year":"2007","journal-title":"Euro Surveill"},{"key":"e_1_2_6_21_1","unstructured":"AguileraJF PagetWJ ManuguerraJC.On behalf of EISS and EuroGROG. 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