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Background: This multi-center study aimed to identify factors affecting fever and delayed defervescence in bacterial meningitis (BM) patients under 3 years of age because of the variability of fever in this patient population., Methods: Only BM patients under 3 years treated at 49 centers in China from November 2018 to end-April 2021 were included in the study. Univariate and multivariate logistic regression analyses were performed to determine factors associated with afebrile presentation and fever of delayed defervescence., Results: A total of 863 BM patients under 3 years were included in the study. Coagulase negative staphylococcus was associated with afebrile presentation (OR = 1.176), while septicaemia and ear-nose-throat infections were associated with fever (P < 0.05). The patients with fever were assigned into early and delayed defervescence groups based on defervescence time (less than and more than or equal to one week). Furthermore, Streptococcus agalactiae meningitis (OR = 1.124), concomitant gastrointestinal infection (OR = 1.276), encephalomalacia (or = 1.339), and subdural effusion (OR = 1.454) were independently associated with delayed defervescence (all P < 0.05)., Conclusions: The findings can aid in the efficient utilization of fever in auxiliary diagnosis and evaluating the condition of the disease., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Streptococcus suis strain 1112S was isolated from a diseased pig in a feedlot from Henan, China, in 2019. The isolate harbored a linezolid resistance gene optrA . WGS data revealed that the optrA gene was associated with a single copy ETAf IS S1S , in tandem with erm (B) and tet (O), located in a novel 72,587 bp integrative and conjugative element (ICE). Notably, this novel element, designated ICE Ssu 1112S, also carried a novel bacitracin resistance locus. ICE Ssu 1112S could be excised from chromosome and transferred to the recipient strain S. suis P1/7 with a frequency of 5.9 × 10 -6 transconjugants per donor cell. This study provided the first description of the coexistence of optrA and a novel bacitracin locus on a multiple antibiotic resistant ICE and highlighted that ICE were major vehicle and contribute to the potential transfer of clinically relevant antibiotic resistance genes. IMPORTANCE Antimicrobial resistance (AMR) caused by the imprudent use of antimicrobials has become a global problem, which poses a serious threat to treatment of S. suis infection in pigs and humans. Importantly, AMR genes can horizontally spread among commensal organisms and pathogenic microbiota, thereby accelerating the dissemination of AMR determinants. These transfers are mainly mediated by mobile genetic elements, including ICEs. In S. suis, ICEs are the major vehicles that contribute to the natural transfers of AMR genes among different bacterial pathogens. However, ICEs that carry optrA and bacitracin resistance locus are rarely investigated in S. suis isolates. Here, we investigated a S. suis isolate carrying an optrA and a novel bacitracin resistance locus, which were co-located on a novel multiple antibiotic resistant ICE Ssu 1112S. Our study suggests that more research is needed to access the real significance of ICEs that horizontally spread clinical important resistance genes.

Sichuan, located in the upper reaches of the Yangtze River, is the gathering place of many rivers and plays an important role in sturgeon aquaculture and wild sturgeon protection in China, where it suffered the severe influence of Streptococcus iniae infection in sturgeon. However, the annual thousands of tons of antibiotic usage in Sichuan may accumulate in water and cause obstacles to the prevention of S. iniae infection. In contrast, the regional antibiotic resistance characteristics have been rarely unknown. Seventeen S. iniae strains were collected from the major sturgeon culture areas in Sichuan, and the genotyping and the distribution of antibiotic resistance profiles (ARPs) and genes (ARGs) of S. iniae were established in this study. The results showed that the isolates could be divided into four subtypes by pulsed-field gel electrophoresis analysis. Besides, most isolates showed multiple resistance to the antibiotic such as amikacin, neomycin, enrofloxacin, lincomycin, and sulfamethoxazole. Also, sturgeon-derived S. iniae has a relatively low similarity with other fish-derived S. iniae in the world but high similarity with three animal-derived pathogens from Sichuan in previous studies. Moreover, a total of 37 ARGs were detected positively based on 95 ARGs detection, in which aac(6')-Ib(aka aacA4)-01, aac(6')-Ib(aka aacA4)-02, aadA1, floR, blaTEM, sulA/folP-03, and tetA-02 were most prevalent. Our study indicated that the ARGs of sturgeon-derived S. iniae were significantly enhanced compared with the ATCC29178 strains and have a risk of accessing more ARGs from other bacteria in water in Sichuan. This study claimed that sturgeon has a potential risk in the prevention and control of Streptococcosis in Sichuan, the upper reaches of Yangtze River, based on the antibiotic resistance analysis of S. iniae, and it may also increase the risk of highly resistant S. iniae transmission into the middle and lower reaches., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Maternal vaginal/rectal colonization of group B streptococcus (GBS) is a main risk for neonatal invasive infection. Efficient determination of GBS colonization in pregnant women is crucial. This study aimed to investigate the prevalence of GBS carriage and evaluate the diagnostic performance of six methodologies for GBS screening conducted in China, including blood agar plate, liquid chromogenic medium, and loop-mediated isothermal amplification (LAMP) without pre-enrichment, chromogenic agar plate with pre-enrichment, and GBS antigen detection without and with pre-enrichment in comparison with the standard reference method (Lim broth-enriched subculture with plating on 5% sheep blood agar). Vaginal/rectal swabs were collected from 1,281 pregnant women at 35-37 weeks of gestation. Of them, 309 were taken in triplicate, one for Lim broth-enriched subculture, one for blood agar plate, and the third for GBS antigen detection (Reagent W); 177 were acquired in duplicate, one for Lim broth-enriched subculture and the other for GBS antigen detection (Reagent H); 502 were obtained in duplicate, one for Lim broth-enriched subculture and the other for liquid chromogenic medium; 158 were collected in duplicate, one for Lim broth-enriched subculture and the other for LAMP; and 135 were inoculated in Lim broth-enriched for GBS antigen detection (Reagent W) and subculture with chromogenic agar plate and 5% blood agar plate. The overall prevalence of GBS carriage was 10.1% (130/1,281, 95% CI: 8.5-12.1%) according to the standard reference method. Compared with the standard reference method, the LAMP had excellent performance of sensitivity (100%, 95%CI: 83.4-100%), specificity (94%, 95%CI: 88.1-97.1%), and Yoden index (0.940); as well as the blood agar plate with sensitivity (81.5%, 95%CI: 61.3-93.0%), specificity (100%, 95%CI: 98.3-100.0%), and Yoden index (0.815). The other four methods were not sufficient to reach the threshold in terms of sensitivity or specificity compared to the standard reference method. Furthermore, for LAMP, results can be obtained within 0.5-1 h, while for blood agar plate, which needed 24-48 h, and further identification was required. Our data suggested that the performance of LAMP was highly comparable to the standard Lim broth-enriched subculture and LAMP is considered as an alternative for fast and accurate GBS screening., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Gao, Deng, Huang, Chang, Zhong, Xie, Guan and Liu.)

Streptococcus agalactiae is a serious pathogen causing severe anthropozoonosis in a broad range of hosts, from aquatic animals to mammals, including humans. S. agalactiae HZAUSC001 was isolated from a moribund tilapia fish exhibiting classic clinical symptoms of streptococcosis in Zhanjiang, Guangdong, China. And it was identified as the etiological factor resulting in fish disease, but was notable because it exhibited attenuated virulence. Here, the genome of S. agalactiae HZAUSC001 was re-analyzed; we assessed the resistome and virulome and deciphered the attenuated characters of HZAUSC001. The S. agalactiae HZAUSC001 genome was assembled into one chromosome with a GC-content of 35.37% and 1972 predicted open reading frames (ORFs). Phylogenetic analysis indicated that it is evolutionarily similar to piscine GBS strains GD201008-001 and ZQ0910. After re-analyzing the published genomic sequence of HZAUSC001, we identified 38 virulence factor genes and one antibiotic-resistance gene. Note that three previously noted virulence genes, bca (C protein alpha-antigen), cpbA (choline-binding protein A) and esp (enterococcal surface protein), were absent in the virulence-attenuated strain S. agalactiae HZAUSC001 but present in the highly virulent strain S. agalactiae GD201008-001. We speculate that the absence of these three virulence genes may be associated with the attenuated traits of the HZAUSC001 strain. Collectively, our study supports that HZAUSC001 may be an excellent candidate for development of an attenuated vaccine, and our results contribute to further understanding of GBS epidemiology and surveillance targets., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Objective: To analyze the characteristics of super-antigen (SAg) of group A Streptococcus pyogenes (GAS), isolated from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. Methods: Throat swab specimens from patients with scarlet fever or pharyngeal infections were collected and tested for GAS. Eleven currently known SAg genes including Spe A , spe C , spe G , spe H , spe I , spe J, spe K , spe L , spe M , sme Z and ssa were tested by real-time PCR while M protein genes ( emm genes) were amplified and sequenced by PCR. Results: A total of 377 GAS were isolated from 6 801 throat swab specimens, with the positive rate as 5.5%. There were obvious changes noticed among spe C, spe G, spe H and spe K in three years. A total of 45 SAg genes profiles were observed, according to the SAgs inclusion. There were significant differences appeared in the frequencies among two of the highest SAg genes profiles between emm 1 and emm 12 strains ( χ (2)=38.196, P <0.001; χ (2)=72.310, P <0.001). There also appeared significant differences in the frequencies of spe A, spe H, spe I and spe J between emm 1 and emm 12 strains ( χ (2)=146.154, P <0.001; χ (2)=52.31, P <0.001; χ (2)=58.43, P <0.001; χ (2)=144.70, P <0.001). Conclusions: Obvious changes were noticed among SAg genes including spe C, spe G, spe H and spe K from patients with scarlet fever or pharyngeal infections in Beijing between 2015-2017. SAg genes including spe A, spe H, spe I and spe J appeared to be associated with the emm 1 and emm 12 strains. More kinds of SAg genes profiles were isolated form GAS but with no significant differences seen in the main SAg genes profiles, during the epidemic period.

The epidemiologic profile of infective endocarditis has changed substantially over the past few years, especially in industrialized countries. Our study evaluates the clinical and pathologic characteristics of infective endocarditis patients treated by cardiac surgery in China during a 12-year period. We retrospectively evaluated 220 surgically treated infective endocarditis patients and analyzed their changes from the beginning of 1998 through 2009. The mean age of the patients increased from 36.9 to 42.7 years during those 12 years (P=0.036). The chief predisposing disease was congenital heart disease (32.8%), rather than rheumatic heart disease (13.2%); this rate did not change significantly during the 12 years. The prevalent congenital lesion was bicuspid aortic valve, the rate of which (55.6%) increased significantly over the 3 time intervals studied (P=0.016). The frequency of infective endocarditis after non-dental surgical and nonsurgical intervention was significantly greater (23.3%) during 1998 through 2001, compared with the 2 intervals that followed (9%; P=0.019). Streptococcus viridans was the most frequent causative agent overall (25.6%). Forty-seven of the 220 patients (21.4%) carried the clinical diagnosis of some other form of heart disease before surgery, but at surgery they were found to have infective endocarditis as the fundamental disease process. Of 47 patients, 33 (70.2%) had either very small or no vegetations but had focal necrosis and inflammation of valve tissue that supported the diagnosis of infective endocarditis.