{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,2]],"date-time":"2026-04-02T23:58:31Z","timestamp":1775174311465,"version":"3.50.1"},"reference-count":39,"publisher":"Oxford University Press (OUP)","issue":"9","license":[{"start":{"date-parts":[[2020,9,2]],"date-time":"2020-09-02T00:00:00Z","timestamp":1599004800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/academic.oup.com\/journals\/pages\/open_access\/funder_policies\/chorus\/standard_publication_model"}],"funder":[{"name":"Pfizer and through Projects","award":["LISBOA-01-0145-FEDER-007660"],"award-info":[{"award-number":["LISBOA-01-0145-FEDER-007660"]}]},{"name":"Pfizer and through Projects","award":["SFRH\/BD\/108380\/2015"],"award-info":[{"award-number":["SFRH\/BD\/108380\/2015"]}]},{"name":"Pfizer and through Projects","award":["SFRH\/PBD\/99638\/2014"],"award-info":[{"award-number":["SFRH\/PBD\/99638\/2014"]}]},{"name":"Fundos Europeus Estruturais e de Investimento"},{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia, Portugal"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2021,5,20]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:sec>\n                  <jats:title>Background<\/jats:title>\n                  <jats:p>Limited information is available on pneumococcal colonization among adults. We studied pneumococcal carriage dynamics in healthy adults using high-sensitivity approaches.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Methods<\/jats:title>\n                  <jats:p>Eighty-seven adults (25\u201350 years old) were followed for 6 months in Portugal. Nasopharyngeal, oropharyngeal, and saliva samples were obtained monthly; pneumococcal carriers were also sampled weekly. Carriage was investigated by quantitative polymerase chain reaction (targeting lytA and piaB) and culture. Positive samples were serotyped.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Results<\/jats:title>\n                  <jats:p>Approximately 20% of the adults were intermittent carriers; 10% were persistent carriers (&amp;gt;4 months). Pneumococcal acquisition and clearance rates were 16.5 (95% confidence interval [CI], 11.2\u201324.2) and 95.9 (95% CI, 62.3\u2013145.0) cases\/1000 person-weeks, respectively. Living with children increased pneumococcal acquisition (hazard ratio, 9.7 [95% CI, 2.6\u201320.5]; P\u2005&amp;lt;\u2005.001). Median duration of carriage was 7 weeks and did not depend on regular contact with children.<\/jats:p>\n               <\/jats:sec>\n               <jats:sec>\n                  <jats:title>Conclusions<\/jats:title>\n                  <jats:p>The pneumococcal carrier state in healthy adults is more dynamic than generally assumed: Acquisition is frequent and duration of carriage is often long. This suggests that some adults may act as reservoirs of pneumococci and hence, depending on the social structure of a community, the magnitude of herd effects potentially attainable through children vaccination may vary. These findings are important when designing strategies to prevent pneumococcal disease in adults.<\/jats:p>\n               <\/jats:sec>","DOI":"10.1093\/infdis\/jiaa558","type":"journal-article","created":{"date-parts":[[2020,9,1]],"date-time":"2020-09-01T11:09:27Z","timestamp":1598958567000},"page":"1590-1600","source":"Crossref","is-referenced-by-count":54,"title":["Dynamics of Pneumococcal Carriage in Adults: A New Look at an Old Paradigm"],"prefix":"10.1093","volume":"223","author":[{"given":"S\u00f3nia T","family":"Almeida","sequence":"first","affiliation":[{"name":"Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Oeiras, Portugal"}]},{"given":"Ana Cristina","family":"Paulo","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Oeiras, Portugal"}]},{"given":"Filipe","family":"Froes","sequence":"additional","affiliation":[{"name":"Unidade de Cuidados Intensivos M\u00e9dico-Cir\u00fargicos, Departamento do T\u00f3rax, Hospital Pulido Valente Centro Hospitalar Universit\u00e1rio Lisboa Norte, Lisboa, Portugal"}]},{"given":"Herm\u00ednia","family":"de Lencastre","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Genetics, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Oeiras, Portugal"},{"name":"Laboratory of Microbiology and Infectious Diseases, The Rockefeller University, New York, USA"}]},{"given":"Raquel","family":"S\u00e1-Le\u00e3o","sequence":"additional","affiliation":[{"name":"Laboratory of Molecular Microbiology of Human Pathogens, Instituto de Tecnologia Qu\u00edmica e Biol\u00f3gica Ant\u00f3nio Xavier, Universidade Nova de Lisboa, Oeiras, 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