{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T11:39:17Z","timestamp":1777376357669,"version":"3.51.4"},"reference-count":39,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T00:00:00Z","timestamp":1767571200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Cell. Infect. Microbiol."],"abstract":"<jats:sec>\n                    <jats:title>Objective<\/jats:title>\n                    <jats:p>\n                      To investigate the clinical characteristics, temporal trends in antimicrobial resistance, and distribution of bacterial serotypes of\n                      <jats:italic>Streptococcus pneumoniae<\/jats:italic>\n                      (\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      )in children in Chongqing region from 2019 to 2024.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      isolates and corresponding epidemiological data were collected from multi-center laboratories. Antimicrobial susceptibility testing was performed in the central research laboratory for each study period from 2019 to 2024\n                      <jats:italic>, and<\/jats:italic>\n                      the results were interpreted according to the breakpoint criteria specified in the Clinical and Laboratory Standards Institute (CLSI) M100-S34 guidelines (2024 edition). Capsular serotyping of\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      was performed using the capsular swelling test, and vaccine coverage rate were calculated.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A total of 17,180\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      isolates were isolated over six years, accounting for 17.2% of all clinically isolated pathogenic bacteria and 45.9% of all Gram-positive bacteria. The isolates were mainly obtained from respiratory tract specimens (97.9%), followed by blood specimens (1.1%).\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      was predominantly isolated from preschool, toddler and Infants, with isolation rates of 32.5%, 30.5% and 25.9%, respectively, together accounting for 88.8% of all\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      isolates. The detection rates of penicillin-susceptible\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      (PSSP), penicillin-intermediate\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      (PISP), and penicillin-resistant\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      (PRSP) were 83.7% (14196\/16964), 14.8% (2513\/16964), and 1.5% (255\/16964), respectively. During the study period, the resistance rate to penicillin, trimethoprim\/sulfamethoxazole, erythromycin, clindamycin, cefotaxime\n                      <jats:italic>, and<\/jats:italic>\n                      cefepime presented a significant downward trend. Except for vancomycin and linezolid. the resistance rates to all tested drugs in the PRSP group were higher than those in the PSSP group. Among different age groups, the resistance rate to trimethoprim\/sulfamethoxazole and clindamycin were highest in toddler stage children, whereas erythromycin resistance was highest in preschool children. The resistance rates to penicillin, chloramphenicol, cefotaxime, and cefepime also differed significantly across age groups. The resistance rates to trimethoprim\/sulfamethoxazole, levofloxacin, and moxifloxacin were higher in non-IPD group than in IPD group, whereas chloramphenicol resistance was lower. The average annual detection of\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      decreased in post-COVID-19, and, except for chloramphenicol, resistance rates to all other antibacterial drugs were lower than those in the pre-COVID-19 period. Thirteen serotypes were identified, except for 8 (1.3%) non-typeable isolates. The top five serotypes, 19F (n = 207, 34.5%),14(n = 65, 10.9%),19A (n = 61, 10.2%), 6B (n = 59, 9.8%) and 1 (n = 52, 8.7%), accounted for 74.1% of all isolates. PCV7, PCV10, and PCV13 covered 388 (64.6%), 440 (73.3%), and 501 (83.5%) strains, respectively.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>\n                      The resistance rates of\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      to penicillin, trimethoprim\/sulfamethoxazole, erythromycin, clindamycin, cefotaxime, and cefepime show significant downward trends over the six-year study period. The pneumococcal conjugate vaccine PCV13 can effectively cover the major drug-resistant serotypes in China, and PCV 13 is therefore recommended for the prevention of\n                      <jats:italic>S. pneumoniae<\/jats:italic>\n                      infection. These findings contribute to informed and clinical policy decisions for prevention and treatment.\n                    <\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fcimb.2025.1700449","type":"journal-article","created":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T06:36:17Z","timestamp":1767594977000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Epidemiology, changing resistance trends and serotypes of Streptococcus pneumoniae in children in Chongqing, China, 2019\u20132024: a multicenter study"],"prefix":"10.3389","volume":"15","author":[{"given":"Jie","family":"Zhao","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chunmei","family":"Jing","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoyan","family":"Yu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhongzheng","family":"Xiong","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yupei","family":"Xiang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fang","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaoqiang","family":"Li","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1965","published-online":{"date-parts":[[2026,1,5]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","first-page":"e65","DOI":"10.1093\/cid\/ciaa1728","article-title":"Impact of the coronavirus disease 2019 (COVID-19) pandemic on invasive pneumococcal disease and risk of pneumococcal coinfection with severe acute respiratory syndrome coronavirus 2 (SARS-coV-2): prospective national cohort study, england","volume":"72","author":"Amin-Chowdhury","year":"2021","journal-title":"Clin. Infect. Dis."},{"key":"B2","doi-asserted-by":"publisher","first-page":"6299","DOI":"10.1016\/j.vaccine.2019.08.073","article-title":"Using pneumococcal carriage studies to monitor vaccine impact in low- and middle-income countries","volume":"37","author":"Chan","year":"2019","journal-title":"Vaccine"},{"key":"B3","volume-title":"Performance standards for antimicrobial susceptibility testing","year":"2024"},{"key":"B4","doi-asserted-by":"publisher","first-page":"1191","DOI":"10.1016\/S1473-3099(18)30310-4","article-title":"Estimates of the global, regional, and national morbidity, mortality, and aetiologies of lower respiratory infections in 195 countries, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016","volume":"18","author":"Collaborators","year":"2018","journal-title":"Lancet Infect. Dis."},{"key":"B5","doi-asserted-by":"publisher","first-page":"2221","DOI":"10.1016\/S0140-6736(22)02185-7","article-title":"Global mortality associated with 33 bacterial pathogens in 2019: a systematic analysis for the Global Burden of Disease Study 2019","volume":"400","author":"Collaborators","year":"2022","journal-title":"Lancet"},{"key":"B6","doi-asserted-by":"publisher","first-page":"430","DOI":"10.1126\/science.1198545","article-title":"Rapid pneumococcal evolution in response to clinical interventions","volume":"331","author":"Croucher","year":"2011","journal-title":"Science"},{"key":"B7","doi-asserted-by":"publisher","first-page":"2203","DOI":"10.21037\/tp-23-547","article-title":"Antimicrobial susceptibility and serotype distribution of Streptococcus pneumoniae isolates among children in Suzhou, China","volume":"12","author":"Dai","year":"2023","journal-title":"Transl. Pediatr."},{"key":"B8","doi-asserted-by":"publisher","first-page":"e00937","DOI":"10.1128\/mBio.00937-20","article-title":"A new pneumococcal capsule type, 10D, is the 100th serotype and has a large cps fragment from an oral streptococcus","volume":"11","author":"Ganaie","year":"2020","journal-title":"mBio"},{"key":"B9","doi-asserted-by":"publisher","first-page":"e93752","DOI":"10.1371\/journal.pone.0093752","article-title":"Molecular characterization and antimicrobial susceptibility of Streptococcus pneumoniae isolated from children hospitalized with respiratory infections in Suzhou, China","volume":"9","author":"Geng","year":"2014","journal-title":"PloS One"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1371\/journal.pmed.1000348","article-title":"Systematic evaluation of serotypes causing invasive pneumococcal disease among children under five: the pneumococcal global serotype project","volume":"7","author":"Johnson","year":"2010","journal-title":"PloS Med."},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1016\/j.nmni.2024.101513","article-title":"Serotype distribution and antimicrobial resistance of Streptococcus pneumoniae isolated from children in Japan, 2023","volume":"62","author":"Kawaguchiya","year":"2024","journal-title":"New Microbes New Infect."},{"key":"B12","doi-asserted-by":"publisher","first-page":"203","DOI":"10.14715\/cmb\/2022.68.2.29","article-title":"Determining the frequency of Streptococcus pneumoniae carriers and its microbial resistance in children","volume":"68","author":"Lei","year":"2022","journal-title":"Cell Mol. Biol. (Noisy-le-grand)."},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1016\/j.micres.2022.127221","article-title":"Epidemiological characteristics and antibiotic resistance mechanisms of Streptococcus pneumoniae: An updated review","volume":"266","author":"Li","year":"2023","journal-title":"Microbiol. Res."},{"key":"B14","doi-asserted-by":"publisher","first-page":"254","DOI":"10.1111\/j.1365-2672.2010.04875.x","article-title":"Molecular characterization of erm(B)- and mef(E)-mediated erythromycin-resistant Streptococcus pneumoniae in China and complete DNA sequence of Tn2010","volume":"110","author":"Li","year":"2011","journal-title":"J. Appl. Microbiol."},{"key":"B15","doi-asserted-by":"publisher","first-page":"e735","DOI":"10.1016\/S2666-5247(22)00158-6","article-title":"Emergence of a multidrug-resistant and virulent Streptococcus pneumoniae lineage mediates serotype replacement after PCV13: an international whole-genome sequencing study","volume":"3","author":"Lo","year":"2022","journal-title":"Lancet Microbe"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.1016\/j.bjid.2024.103734","article-title":"Serotype distribution and antimicrobial resistance of pediatric Streptococcus pneumoniae isolated from inpatients and outpatients at Beijing Children\u2019s Hospital","volume":"28","author":"Lyu","year":"2024","journal-title":"Braz. J. Infect. Dis."},{"key":"B17","doi-asserted-by":"publisher","first-page":"249","DOI":"10.2147\/idr.S397513","article-title":"Bacterial epidemiology and antimicrobial resistance profiles of respiratory specimens of children with pneumonia in hainan, China","volume":"16","author":"Mai","year":"2023","journal-title":"Infect. Drug Resist."},{"key":"B18","doi-asserted-by":"publisher","first-page":"665","DOI":"10.1007\/s42770-019-00198-9","article-title":"Serotype distribution and antimicrobial resistance patterns of invasive pneumococcal disease isolates from children in mainland China-a systematic review","volume":"51","author":"Men","year":"2020","journal-title":"Braz. J. Microbiol."},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1172\/jci157124","article-title":"Streptococcus pneumoniae colonization associates with impaired adaptive immune responses against SARS-CoV-2","volume":"132","author":"Mitsi","year":"2022","journal-title":"J. Clin. Invest."},{"key":"B20","doi-asserted-by":"publisher","first-page":"336","DOI":"10.1080\/21645515.2015.1075678","article-title":"Theory and strategy for Pneumococcal vaccines in the elderly","volume":"12","author":"Namkoong","year":"2016","journal-title":"Hum. Vaccin Immunother."},{"key":"B21","doi-asserted-by":"publisher","first-page":"256","DOI":"10.1038\/s41579-024-01116-z","article-title":"Streptococcus pneumoniae epidemiology, pathogenesis and control","volume":"23","author":"Narciso","year":"2025","journal-title":"Nat. Rev. Microbiol."},{"key":"B22","doi-asserted-by":"publisher","first-page":"3703","DOI":"10.1128\/AAC.00237-11","article-title":"Susceptibility of Streptococcus pneumoniae to fluoroquinolones in Canada","volume":"55","author":"Patel","year":"2011","journal-title":"Antimicrob. Agents Chemother."},{"key":"B23","doi-asserted-by":"publisher","first-page":"e00329","DOI":"10.1128\/JCM.00329-21","article-title":"New pneumococcal serotype 15D","volume":"59","author":"Pimenta","year":"2021","journal-title":"J. Clin. Microbiol."},{"key":"B24","doi-asserted-by":"publisher","first-page":"000703.v4","DOI":"10.1099\/acmi.0.000703.v4","article-title":"Nasopharyngeal carriage rate, serotype distribution, and antimicrobial profiles of Streptococcus pneumoniae among patients with acute respiratory tract infection in Manado, North Sulawesi, Indonesia","volume":"6","author":"Purwanto","year":"2024","journal-title":"Access Microbiol"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2023.1332472","article-title":"Prevalence and resistance characteristics of multidrug-resistant Streptococcus pneumoniae isolated from the respiratory tracts of hospitalized children in Shenzhen, China","volume":"13","author":"Shi","year":"2023","journal-title":"Front. Cell Infect. Microbiol."},{"key":"B26","doi-asserted-by":"publisher","first-page":"557","DOI":"10.1016\/j.jinf.2020.07.035","article-title":"Streptococcus pneumoniae serotype distribution and antimicrobial nonsusceptibility trends among adults with pneumonia in the United States, 2009\u20132017","volume":"81","author":"Suaya","year":"2020","journal-title":"J. Infect."},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.3389\/fpubh.2023.1110903","article-title":"Antibiotic resistance of Streptococcus pneumoniae in Vietnamese children with severe pneumonia: a cross-sectional study","volume":"11","author":"Tran-Quang","year":"2023","journal-title":"Front. Public Health"},{"key":"B28","doi-asserted-by":"publisher","first-page":"943","DOI":"10.3390\/pathogens12070943","article-title":"Molecular epidemiology of streptococcus pneumoniae detected in hospitalized pediatric acute respiratory infection cases in central Vietnam","volume":"12","author":"Wambugu","year":"2023","journal-title":"Pathogens"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1186\/s40249-024-01175-7","article-title":"Prevalence and serotype distribution of nasopharyngeal carriage of Streptococcus pneumoniae among healthy children under 5 years of age in Hainan Province, China","volume":"13","author":"Wang","year":"2024","journal-title":"Infect. Dis. Poverty."},{"key":"B30","doi-asserted-by":"publisher","first-page":"7858","DOI":"10.1016\/j.vaccine.2020.10.005","article-title":"Serotype distribution of Streptococcus pneumoniae isolated from children hospitalized in Beijing children\u2019s hospital (2013-2019)","volume":"38","author":"Wang","year":"2020","journal-title":"Vaccine"},{"key":"B31","doi-asserted-by":"publisher","first-page":"6189","DOI":"10.1016\/j.vaccine.2021.09.011","article-title":"Low vaccination coverage of pneumococcal conjugate vaccines (PCVs) in Shanghai, China: A database analysis based on birth cohorts from 2012 to 2020","volume":"39","author":"Wang","year":"2021","journal-title":"Vaccine"},{"key":"B32","doi-asserted-by":"publisher","DOI":"10.3389\/fcimb.2021.726740","article-title":"Molecular characterization based on whole-genome sequencing of streptococcus pneumoniae in children living in southwest China during 2017-2019","volume":"11","author":"Yan","year":"2021","journal-title":"Front. Cell Infect. Microbiol."},{"key":"B33","doi-asserted-by":"publisher","DOI":"10.3389\/fpubh.2024.1490401","article-title":"Antibiotic susceptibility testing and molecular characterization based on whole-genome sequencing of Streptococcus pneumoniae isolates from pediatric infections at the National Regional Medical Center of Southwest China during the COVID-19 pandemic","volume":"12","author":"Yan","year":"2024","journal-title":"Front. Public Health"},{"key":"B34","doi-asserted-by":"publisher","first-page":"2823","DOI":"10.2147\/IDR.S511161","article-title":"Shandong provincial microbiome research center children B, fungal resistance monitoring research N. Bacterial epidemiology and antimicrobial resistance in children in shandong province, China, 2017-2022: A multicentre retrospective study","volume":"18","author":"Yang","year":"2025","journal-title":"Infect. Drug Resist."},{"key":"B35","doi-asserted-by":"publisher","first-page":"535","DOI":"10.3390\/microorganisms9030535","article-title":"Bacterial meningitis in children: neurological complications, associated risk factors, and prevention","volume":"9","author":"Zainel","year":"2021","journal-title":"Microorganisms"},{"key":"B36","doi-asserted-by":"publisher","first-page":"46","DOI":"10.1186\/s13073-023-01200-8","article-title":"Phylogenomic insights into evolutionary trajectories of multidrug resistant S. pneumoniae CC271 over a period of 14 years in China","volume":"15","author":"Zeng","year":"2023","journal-title":"Genome Med."},{"key":"B37","doi-asserted-by":"publisher","first-page":"2117","DOI":"10.2147\/idr.S256663","article-title":"Investigation of antibiotic resistance, serotype distribution, and genetic characteristics of 164 invasive streptococcus pneumoniae from north China between april 2016 and october 2017","volume":"13","author":"Zhao","year":"2020","journal-title":"Infect. Drug Resist."},{"key":"B38","doi-asserted-by":"publisher","first-page":"5069","DOI":"10.2147\/idr.S374805","article-title":"Antimicrobial resistance trends of the most common causative pathogens associated with community-acquired respiratory infections in China: 2009-2018","volume":"15","author":"Zhao","year":"2022","journal-title":"Infect. Drug Resist."},{"key":"B39","doi-asserted-by":"publisher","first-page":"e0054622","DOI":"10.1128\/spectrum.00546-22","article-title":"Characterization of Streptococcus pneumoniae Macrolide Resistance and Its Mechanism in Northeast China over a 20-Year Period","volume":"10","author":"Zhou","year":"2022","journal-title":"Microbiol. Spectr."}],"container-title":["Frontiers in Cellular and Infection Microbiology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2025.1700449\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,5]],"date-time":"2026-01-05T06:36:17Z","timestamp":1767594977000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fcimb.2025.1700449\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,5]]},"references-count":39,"alternative-id":["10.3389\/fcimb.2025.1700449"],"URL":"https:\/\/doi.org\/10.3389\/fcimb.2025.1700449","relation":{},"ISSN":["2235-2988"],"issn-type":[{"value":"2235-2988","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,5]]},"article-number":"1700449"}}