{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,19]],"date-time":"2026-08-19T17:44:24Z","timestamp":1787161464568,"version":"build-2736575974"},"reference-count":31,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T00:00:00Z","timestamp":1712620800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100004319","name":"Pfizer","doi-asserted-by":"publisher","award":["ISR 53234577"],"award-info":[{"award-number":["ISR 53234577"]}],"id":[{"id":"10.13039\/100004319","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Vaccines"],"abstract":"<jats:p>We aimed to assess the prevalence of nasopharyngeal pneumococcal carriage and to determine serotype distribution, antibiotic susceptibility patterns, and evolutionary dynamics of Streptococcus pneumoniae isolates in healthy under-five children. Nasopharyngeal swabs were collected from healthy children over three survey periods between 2020 and 2022. All pneumococcal isolates were serotyped and tested for antimicrobial susceptibility. A total of 309 S. pneumoniae isolates were collected, with an overall prevalence of nasopharyngeal pneumococcal carriage of 24.4% (CI95%: [22\u201326.8%]). These isolates were classified into 25 different serotypes. The most common serotypes were 14 (14.9%), 19F (12%), 6B (10.4%), and 23F (7.4%), which are covered by the PCV10 vaccine, as well as 19A (8.4%) and 6A (7.8%), which are covered by the PCV13 vaccine. A significant decrease in the proportion of serotype 19F (p = 0.001) and an increase in serotypes 19A (p = 0.034) and 6A (p = 0.029) were observed between the three survey periods. Multidrug resistance (MDR) was noted for 56.6% of the isolates. A significant association with antimicrobial resistance was observed for the most frequent serotypes, mainly serotype 19A. In conclusion, one-quarter of healthy under-five children in Tunisia carried S. pneumoniae in their nasopharynx. A dominance of vaccine serotypes significantly associated with antimicrobial resistance was recorded.<\/jats:p>","DOI":"10.3390\/vaccines12040393","type":"journal-article","created":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T08:55:12Z","timestamp":1712652912000},"page":"393","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":10,"title":["Nasopharyngeal Carriage of Streptococcus pneumoniae in Tunisian Healthy under-Five Children during a Three-Year Survey Period (2020 to 2022)"],"prefix":"10.3390","volume":"12","author":[{"given":"Nourelhouda","family":"Ben Ayed","sequence":"first","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8090-3140","authenticated-orcid":false,"given":"Sonia","family":"Ktari","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jihen","family":"Jdidi","sequence":"additional","affiliation":[{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"},{"name":"Community Health and Epidemiology Department, Hedi Chaker University Hospital, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Omar","family":"Gargouri","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0007-7002-9262","authenticated-orcid":false,"given":"Fahmi","family":"Smaoui","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Haifa","family":"Hachicha","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Boutheina","family":"Ksibi","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sonda","family":"Mezghani","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Basma","family":"Mnif","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Faouzia","family":"Mahjoubi","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, University of Sfax, Sfax 3029, Tunisia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5140-2216","authenticated-orcid":false,"given":"Adnene","family":"Hammami","sequence":"additional","affiliation":[{"name":"Laboratory of Microbiology, Research Laboratory for Microorganisms and Human Disease LR03SP03, Habib Bourguiba University Hospital, University of Sfax, Sfax 3029, Tunisia"},{"name":"Faculty of Medicine of Sfax, 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