{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,11]],"date-time":"2026-03-11T03:41:02Z","timestamp":1773200462052,"version":"3.50.1"},"reference-count":37,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,7,1]],"date-time":"2021-07-01T00:00:00Z","timestamp":1625097600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001871","name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia","doi-asserted-by":"publisher","award":["PTDC\/DTP-EPI\/1555\/2014"],"award-info":[{"award-number":["PTDC\/DTP-EPI\/1555\/2014"]}],"id":[{"id":"10.13039\/501100001871","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/100004319","name":"Pfizer","doi-asserted-by":"publisher","award":["Unrestricted Investigator Initiated Project"],"award-info":[{"award-number":["Unrestricted Investigator Initiated Project"]}],"id":[{"id":"10.13039\/100004319","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>The introduction of pneumococcal conjugate vaccines PCV7 and PCV13 led to decreases in incidence of pediatric invasive pneumococcal disease (pIPD) and changes in serotype distribution. We evaluated the consequences of higher vaccine uptake after the introduction of PCV13 in the National Immunization Plan (NIP) in 2015. Besides culture and conventional serotyping, the use of molecular methods to detect and serotype pneumococci in both pleural and cerebrospinal fluid samples contributed to 30% of all pIPD (n = 232) in 2015\u20132018. The most frequently detected serotypes were: 3 (n = 59, 26%), 10A (n = 17, 8%), 8 (n = 16, 7%) and 19A (n = 10, 4%). PCV13 serotypes still accounted for 46% of pIPD cases. Serotypes not included in any currently available conjugate vaccine (NVT) are becoming important causes of pIPD, with the increases in serotypes 8 and 33F being of particular concern given the importance of serotype 8 in adult IPD and the antimicrobial resistance of serotype 33F isolates. This study highlights the importance of using molecular methods in pIPD surveillance since these allowed a better case ascertainment and the identification of serotype 3 as the leading cause of pIPD. Even in a situation of vaccine uptake &gt;95% for 3 years, PCV13 serotypes remain important causes of pIPD.<\/jats:p>","DOI":"10.3390\/microorganisms9071428","type":"journal-article","created":{"date-parts":[[2021,7,1]],"date-time":"2021-07-01T21:55:52Z","timestamp":1625176552000},"page":"1428","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":19,"title":["Pediatric Invasive Pneumococcal Disease Three Years after PCV13 Introduction in the National Immunization Plan\u2014The Continued Importance of Serotype 3"],"prefix":"10.3390","volume":"9","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9681-0574","authenticated-orcid":false,"given":"Catarina","family":"Silva-Costa","sequence":"first","affiliation":[{"name":"Faculdade de Medicina, Instituto de Microbiologia, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3658-1102","authenticated-orcid":false,"given":"Joana","family":"Gomes-Silva","sequence":"additional","affiliation":[{"name":"Faculdade de Medicina, Instituto de Microbiologia, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal"}]},{"given":"L\u00facia","family":"Prados","sequence":"additional","affiliation":[{"name":"Faculdade de Medicina, Instituto de Microbiologia, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4084-6233","authenticated-orcid":false,"given":"M\u00e1rio","family":"Ramirez","sequence":"additional","affiliation":[{"name":"Faculdade de Medicina, Instituto de Microbiologia, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal"}]},{"given":"Jos\u00e9","family":"Melo-Cristino","sequence":"additional","affiliation":[{"name":"Faculdade de Medicina, Instituto de Microbiologia, Instituto de Medicina Molecular, Universidade de Lisboa, 1649-028 Lisboa, Portugal"}]},{"name":"on behalf of the Portuguese Group for the Study of Streptococcal Infections","sequence":"additional","affiliation":[]},{"name":"the Portuguese Study Group of Invasive Pneumococcal Disease of the Pediatric Infectious Disease Society","sequence":"additional","affiliation":[]}],"member":"1968","published-online":{"date-parts":[[2021,7,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"20750","DOI":"10.2807\/1560-7917.ES2014.19.12.20750","article-title":"Decreasing Incidence and Changes in Serotype Distribution of Invasive Pneumococcal Disease in Persons Aged under 18 Years since Introduction of 10-Valent and 13-Valent Conjugate Vaccines in Portugal, July 2008 to June 2012","volume":"19","author":"Aguiar","year":"2014","journal-title":"Euro Surveill."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"835","DOI":"10.1111\/j.1469-0691.2008.02031.x","article-title":"Changes in Streptococcus Pneumoniae Serotypes Causing Invasive Disease with Non-Universal Vaccination Coverage of the Seven-Valent Conjugate Vaccine","volume":"14","author":"Aguiar","year":"2008","journal-title":"Clin. 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