{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,15]],"date-time":"2026-08-15T02:41:01Z","timestamp":1786761661820,"version":"build-2736575974"},"reference-count":44,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2022,10,18]],"date-time":"2022-10-18T00:00:00Z","timestamp":1666051200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ghana Scholarship Secretariat","award":["2016\/17 (57251550)"],"award-info":[{"award-number":["2016\/17 (57251550)"]}]},{"name":"Bundesministerium f\u00fcr Bildung und Forschung","award":["2016\/17 (57251550)"],"award-info":[{"award-number":["2016\/17 (57251550)"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Preventive strategies involving the use of pneumococcal conjugate vaccines (PCVs) are known to drastically reduce pneumococcal disease. However, PCV vaccination has been plagued with serotype replacement by non-PCV serotypes. In this study, we describe the prevalence and molecular characteristics of non-PCV13 serotypes (non-vaccine serotypes, NVTs) from pneumococcal carriage isolates obtained from children &lt; 5 years old in Cape Coast, Ghana, after PCV introduction. The isolates were subjected to antibiotic susceptibility testing and multilocus sequence typing (MLST), and molecular techniques were used to detect the presence of virulence genes. Serotypes 11A, 13, 15B, 23B, and 34 formed the top five of the 93 NVT isolates. As such, 20 (21.5%), 49 (48.4%), and 70 (74.3%) isolates were non-susceptible to penicillin, tetracycline, and cotrimoxazole, respectively. Sixteen (17.2%) multidrug-resistant isolates were identified. However, non-susceptibility to ceftriaxone and erythromycin was low and all isolates were fully susceptible to levofloxacin, linezolid, and vancomycin. Whereas pcpA, pavB, lytA, and psrP genes were detected in nearly all serotypes, pilus islet genes were limited to serotypes 11A, 13, and 23B. MLST for predominant serotype 23B isolates revealed three known and seven novel sequence types (STs). ST172 and novel ST15111 were the most dominant and both STs were related to PMEN clone Columbia23F-26 (ST338). In conclusion, non-PCV13 serotype 23B was the most prevalent, with characteristics of rapid clonal expansion of ST172 and ST15111, which are related to international clones of the pneumococcus. Continuous monitoring of NVTs in Ghana is, therefore, essential, as they have the potential to cause invasive disease, show high antibiotic resistance, and attenuate the effects of PCV vaccination.<\/jats:p>","DOI":"10.3390\/microorganisms10102054","type":"journal-article","created":{"date-parts":[[2022,10,19]],"date-time":"2022-10-19T00:58:51Z","timestamp":1666141131000},"page":"2054","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Molecular Characterization and Antibiotic Susceptibility of Non-PCV13 Pneumococcal Serotypes among Vaccinated Children in Cape Coast, Ghana"],"prefix":"10.3390","volume":"10","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1596-8543","authenticated-orcid":false,"given":"Richael O.","family":"Mills","sequence":"first","affiliation":[{"name":"Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, 17489 Greifswald, Germany"},{"name":"Department of Biomedical Sciences, School of Allied Health Science, University of Cape Coast, Cape Coast PMB TF0494, Ghana"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mohammed R.","family":"Abdullah","sequence":"additional","affiliation":[{"name":"Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, 17489 Greifswald, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Samuel A.","family":"Akwetey","sequence":"additional","affiliation":[{"name":"Department of Biomedical Sciences, School of Allied Health Science, University of Cape Coast, Cape Coast PMB TF0494, Ghana"},{"name":"Department of Clinical Microbiology, School of Medicine, University of Development Studies, Tamale PMB TF0494, Ghana"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dorcas C.","family":"Sappor","sequence":"additional","affiliation":[{"name":"Department of Medical Laboratory Sciences, School of Allied Health Sciences, University of Cape Coast, Cape Coast PMB TF0494, Ghana"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2781-7403","authenticated-orcid":false,"given":"Johan A.","family":"Bolivar","sequence":"additional","affiliation":[{"name":"Genetics, Regeneration and Cancer (GRC), University Research Centre (SIU), University of Antioquia (UdeA), Medell\u00edn 050010, Colombia"},{"name":"Basic and Applied Microbiology (MICROBA), School of Microbiology, University of Antioquia Medellin, Antioquia 050010, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5957-9163","authenticated-orcid":false,"given":"Gustavo","family":"G\u00e1mez","sequence":"additional","affiliation":[{"name":"Genetics, Regeneration and Cancer (GRC), University Research Centre (SIU), University of Antioquia (UdeA), Medell\u00edn 050010, Colombia"},{"name":"Basic and Applied Microbiology (MICROBA), School of Microbiology, University of Antioquia Medellin, Antioquia 050010, Colombia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mark P. G.","family":"van der Linden","sequence":"additional","affiliation":[{"name":"German National Reference Center for Streptococci, Department of Medical Microbiology, University Hospital RWTH Aachen, 52074 Aachen, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6382-6681","authenticated-orcid":false,"given":"Sven","family":"Hammerschmidt","sequence":"additional","affiliation":[{"name":"Department of Molecular Genetics and Infection Biology, Interfaculty Institute for Genetics and Functional Genomics, Center for Functional Genomics of Microbes, University of Greifswald, 17489 Greifswald, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,10,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e744","DOI":"10.1016\/S2214-109X(18)30247-X","article-title":"Burden of Streptococcus pneumoniae and Haemophilus influenzae type b disease in children in the era of conjugate vaccines: Global, regional, and national estimates for 2000\u201315","volume":"6","author":"Wahl","year":"2018","journal-title":"Lancet Glob. 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