AUTHOR=Ma Han-rui , Xu Hui-jiao , Wang Xin , Bu Zhao-yang , Yao Teng , Zheng Zun-rong , Sun Yang , Ji Xue , Liu Jun 

TITLE=Molecular characterization and antimicrobial susceptibility of human Brucella in Northeast China

JOURNAL=Frontiers in Microbiology

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2023.1137932

DOI=10.3389/fmicb.2023.1137932

ISSN=1664-302X

ABSTRACT=<sec><title>Introduction</title><p>Northeast China has always been an area with severe brucellosis prevalence. This study will identify <italic>Brucella</italic> in Northeast China and test its resistance to antibiotics, in order to clarify its resistance mechanism. <italic>Brucella</italic> is a widespread and highly pathogenic bacteria that poses serious threats to public health and animal husbandry.</p></sec><sec><title>Methods</title><p>In this study, 61 <italic>Brucella</italic> isolates were identified by abortus-melitensis-ovis-suis polymerase chain reaction (AMOS-PCR) for biotypes and epidemic potential was clarified by multi-locus sequence analysis. Whole-genome sequencing (WGS) was performed and the antibiotic susceptibility of the <italic>Brucella</italic> strains against 13 antibiotics was detected with the use of E-test strips.</p></sec><sec><title>Results</title><p>The results showed that all of the isolates were <italic>Brucella melitensis</italic> ST8, group CC4 with little genetic variation and obvious geographical characteristics. All 61 <italic>Brucella</italic> isolates were sensitive to doxycycline, tetracycline, minocycline, levofloxacin, ciprofloxacin, gentamicin, and streptomycin, while 24.6%, 86.9%, 65.6%, 27.9%, 3.3%, and 1.6% were resistant to rifampin, azithromycin, cefepime, cefoperazone/sulbactam, cefotaxime, and meperidine/sulfamethoxazole, respectively. This is the first report of cephalosporin-resistant <italic>B. melitensis</italic> in China. The WGS results indicated that about 60% of the antibiotic resistance genes were associated with efflux pumps (mainly the resistance nodulation division family).</p></sec><sec><title>Discussion</title><p>Brucellosis is usually treated with antibiotics for several months, which can easily lead to the emergence of antibiotic resistance. To ensure the effectiveness and safety of antibiotics for treatment of brucellosis, continuous surveillance of antibiotic susceptibility is especially important.</p></sec>