Molecular characterization of Streptococcus pneumoniae isolated from pediatric patients in Shanghai, China

Abstract

BackgroundStreptococcus pneumoniae is a major cause of bacterial infection among infants and young children with high morbidity and mortality. The serotype distribution of S. pneumoniae varies with geography, time, age, and disease.AimWe aimed to investigate the current status of molecular characteristics of S. pneumoniae strains isolated from pediatric patients in Shanghai, China.MethodsBetween 2016 and 2018, 73 clinical S. pneumoniae isolates were characterized by capsular serotype, multilocus sequence typing, antibiotic susceptibility, and resistant genes.ResultsThe most common serotypes were 19F (39.7%), 19A (16.4%), 6A (11.0%), 14 (9.6%), and 6B (8.2%). The coverage rates of the 7‐, 10‐ and 13‐valent pneumococcal conjugate vaccines were 64.4%, 64.4%, and 91.8%, respectively. The five predominant sequence types were ST271 (37.0%), ST320 (19.2%), ST3173 (11.0%), ST876 (6.8%), and ST81 (4.1%), which were mainly associated with serotypes 19F, 19A, 6A, 14, and 23F, respectively. The rates of resistance to penicillin and ceftriaxone were 21.9% and 39.7%, respectively. All strains displayed resistance to macrolides, 54.8% of which possessed both erm(B) and mef(A/E) genes, and 41.1% carried the erm(B) gene alone. Tn2010 (41.1%) was the most common transposon.ConclusionsClonal complex 271 (Taiwan19F‐14 clone) played a dominant role in the dissemination of pneumococcal isolates. The prevalent serotypes indicated a lack of the 7‐valent pneumococcal conjugate vaccine, which has not been included in national immunization programs in mainland China. The high rate of macrolide resistance made the empirical use of macrolides alone not suitable for treating pediatric pneumococcal disease.

Molecular Characterization Based on Whole-Genome Sequencing of Streptococcus pneumoniae in Children Living in Southwest China During 2017-2019

“…The most prevalent serotypes (19F, 19A, 6B, 6A, and 14) in our regions were similar to those in other regions of China, such as Chongqing (19F, 6A/B, 19A) (Yu et al, 2019), Eastern region of Shanghai (19F, 19A, 6A, 14, 6B) (Wang et al, 2020b), Northern region of Beijing (19F, 19A, 23F, 14, 6A) (Wang et al, 2020a) and Southern region of Liuzhou (19F, 6B, 19A, 23F, 14) (Li et al, 2018), suggesting a general distribution of pneumococcal serotypes in China. However, the prevalence of pneumococcal serotypes in our region was slightly different from those in developing countries and regions e.g.…”

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“…The present study shows that ST271, ST320, ST90 and ST876 were the most prevalent STs in Southwest China, which were similar to those in other regions in China (Li et al, 2018;Wang et al, 2020b). The present study further revealed 8 novel STs which accounted for 6.25% of all isolates (8/128), suggesting a higher variation and mutation rate for S. pneumoniae over other respiratory pathogenic bacteria e.g.…”

“…Although 14 ministries of China jointly issued a 5-year national action plan to control antimicrobial resistance (NAP) in 2016, 51.4% of prescriptions related to antibiotics, including the use of macrolides, remain inappropriate (Zhao et al, 2021). Similar to the results from other reports (Li et al, 2019;Wang et al, 2020b), the isolates were highly resistant to CLI in this work, thus, CLI may be not suitable for the treatment of S. pneumoniae infections. In addition, due to the potential toxic effects on children, the use of CHL (bone marrow suppression), TET (enamel hypoplasia), quinolones (achondroplasia) and sulphonamides (jaundice) is prohibited or restricted at different ages.…”

“…PCVs-covered serotypes decreased slightly in this region (PCV7: 68.7% vs. 50.0%; PCV10: 69.7% vs. 50.8%; PCV13: 93.3% vs. 77.3%), which may attribute to the introduction of PCV13 in 2017. The serotype coverage of PCV13 here is slightly lower than that in other regions in China (Beijing: 83.2%; Shanghai: 91.8%) (Wang et al, 2020a;Wang et al, 2020b) but remains higher than that in other developed countries (Spain: 52%; USA: 41.4%; Japan: 37.5%) (Richter et al, 2013;Nakano et al, 2016;Ciruela et al, 2018). In agreement with the results reported by Wang et al (Wang et al, 2020a), the present study also shows that the serotype coverage for PCVs was higher for IPD strains than non-IPD strains, and serotype 14 strain was several times more frequently isolated in IPD patients than non-IPD patients.…”

Genotypic and phenotypic characteristics of Streptococcus pneumoniae from community-acquired pneumonia patients and healthy asymptomatic participants in Sichuan province, China

“…It is well known that the distribution of S. pneumoniae serotypes changes over age, geographic region, time, and diseases [ 27 , 28 ]. In our study, the most frequent serotypes in CAP carriers group were 3, 19F, 19A, which were similar to other recent studies in China [ 16 , 29 ], however different with serotypes in Italy [ 30 ].…”