{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,20]],"date-time":"2026-08-20T16:07:49Z","timestamp":1787242069882,"version":"build-2736575974"},"reference-count":38,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2021,6,20]],"date-time":"2021-06-20T00:00:00Z","timestamp":1624147200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100000030","name":"Centers for Disease Control and Prevention","doi-asserted-by":"publisher","award":["1U01GH000028-04"],"award-info":[{"award-number":["1U01GH000028-04"]}],"id":[{"id":"10.13039\/100000030","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000060","name":"National Institute of Allergy and Infectious Diseases","doi-asserted-by":"publisher","award":["HHSN272201400006C"],"award-info":[{"award-number":["HHSN272201400006C"]}],"id":[{"id":"10.13039\/100000060","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>More information about influenza in low- and middle-income countries could guide the establishment of pediatric influenza vaccine programs. This study (1) characterizes the burden of influenza in infants, and (2) compares signs and symptoms by prior influenza vaccination or influenza illness. Newborns from Managua, Nicaragua, were followed for two years. Data came from primary medical appointments, PCR testing, and parents\u2019 daily symptom diaries. Logistic regression models estimated associations between preceding vaccination or illness and influenza incidence. Linear models compared duration of illness by prior vaccination or influenza illness. Among 833 infants, 31% had PCR-positive influenza, and 28% were vaccinated against influenza. Four (&lt;0.5%) were fully vaccinated. Overall, influenza incidence was 21.0 (95% confidence interval (CI): 18.8, 23.2) per 100 person-years. Incidence was lower among those with prior influenza compared with those without preceding illness or vaccination (OR: 0.64, 95% CI: 0.44, 0.94). Partially vaccinated children had 1 day less fever than those without prior illness or vaccination (p = 0.049). A large proportion of children &lt;2 years in Nicaragua contract influenza. Illness was attenuated for those partially vaccinated. Since few children were fully vaccinated, future studies will need to consider the effectiveness of a two-dose vaccination schedule.<\/jats:p>","DOI":"10.3390\/vaccines9060676","type":"journal-article","created":{"date-parts":[[2021,6,20]],"date-time":"2021-06-20T21:50:15Z","timestamp":1624225815000},"page":"676","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Influenza Illness and Partial Vaccination in the First Two Years of Life"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4691-7802","authenticated-orcid":false,"given":"Abram L.","family":"Wagner","sequence":"first","affiliation":[{"name":"Department of Epidemiology, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2333-1748","authenticated-orcid":false,"given":"Lionel","family":"Gresh","sequence":"additional","affiliation":[{"name":"Sustainable Sciences Institute, Managua 14007, Nicaragua"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nery","family":"Sanchez","sequence":"additional","affiliation":[{"name":"Sustainable Sciences Institute, Managua 14007, Nicaragua"},{"name":"Centro de Salud S\u00f3crates Flores Vivas, Ministry of Health, Managua 12014, Nicaragua"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guillermina","family":"Kuan","sequence":"additional","affiliation":[{"name":"Sustainable Sciences Institute, Managua 14007, Nicaragua"},{"name":"Centro de Salud S\u00f3crates Flores Vivas, Ministry of Health, Managua 12014, Nicaragua"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5571-9774","authenticated-orcid":false,"given":"John","family":"Kubale","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Roger","family":"Lopez","sequence":"additional","affiliation":[{"name":"Sustainable Sciences Institute, Managua 14007, Nicaragua"},{"name":"Laboratorio Nacional de Virolog\u00eda, Centro Nacional de Diagn\u00f3stico y Referencia, Ministry of Health, Managua 16064, Nicaragua"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sergio","family":"Ojeda","sequence":"additional","affiliation":[{"name":"Sustainable Sciences Institute, Managua 14007, Nicaragua"},{"name":"Centro de Salud S\u00f3crates Flores Vivas, Ministry of Health, Managua 12014, Nicaragua"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eduardo","family":"Azziz-Baumgartner","sequence":"additional","affiliation":[{"name":"Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Angel","family":"Balmaseda","sequence":"additional","affiliation":[{"name":"Sustainable Sciences Institute, Managua 14007, Nicaragua"},{"name":"Laboratorio Nacional de Virolog\u00eda, Centro Nacional de Diagn\u00f3stico y Referencia, Ministry of Health, Managua 16064, Nicaragua"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9352-7877","authenticated-orcid":false,"given":"Aubree","family":"Gordon","sequence":"additional","affiliation":[{"name":"Department of Epidemiology, School of Public Health, University of Michigan, 1415 Washington Heights, Ann Arbor, MI 48109, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,20]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1285","DOI":"10.1016\/S0140-6736(17)33293-2","article-title":"Estimates of global seasonal influenza-associated respiratory mortality: A modelling study","volume":"391","author":"Iuliano","year":"2018","journal-title":"Lancet"},{"key":"ref_2","unstructured":"World Health Organization (2021, May 06). 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