AUTHOR=Shi Wei , Du Qianqian , Yuan Lin , Gao Wei , Wang Qing , Yao Kaihu 

TITLE=Antibiotic Resistance and Molecular Biological Characteristics of Non-13-Valent-Pneumococcal Conjugate Vaccine Serogroup 15 Streptococcus pneumoniae Isolated From Children in China

JOURNAL=Frontiers in Microbiology

VOLUME=12

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2021.778985

DOI=10.3389/fmicb.2021.778985

ISSN=1664-302X

ABSTRACT=<p><bold>Background:</bold> The isolation rate of serogroup 15 <italic>Streptococcus pneumoniae</italic> has been increasing since developing countries began administering the 13-valent pneumococcal conjugate vaccine.</p><p><bold>Methods:</bold> We detected the antibiotic resistance and molecular characteristics of 126 serogroup 15 <italic>S. pneumoniae</italic> strains isolated from children in China. Serotypes were determined via the Quellung reaction. Antibiotic resistance was tested using the <italic>E</italic>-test or disc diffusion method. Sequence types were assigned via multilocus sequence typing. Data were analyzed using WHONET 5.6 software.</p><p><bold>Results:</bold> The frequencies of <italic>S. pneumoniae</italic> serotypes 15A, 15B, 15C, and 15F were 29.37, 40.48, 28.57, and 1.59%, respectively. Continuous-monitoring data from Beijing showed that the annual isolation rates of serogroup 15 <italic>S. pneumoniae</italic> were 7.64, 7.17, 2.58, 4.35, 3.85, 7.41, and 10.53%, respectively, from 2013 to 2019. All 126 serogroup 15 strains were susceptible to vancomycin and ceftriaxone. The non-susceptibility rate to penicillin was 78.57%. All strains were resistant to erythromycin with high minimum inhibitory concentrations (MICs). The multidrug resistance rate was 78.57%. The most common clonal complexes were CC3397, CC6011, CC10088, CC9785, and ST8589.</p><p><bold>Conclusion:</bold> Serogroup 15 <italic>S. pneumoniae</italic> is common among children in China, and these strains should be continuously monitored.</p>