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Objective To study the epidemiology of mold infections in China. Methods Based on the surveillance data of 19 hospitals participating in the China Hospital Invasive Fungal Surveillance Net from Jan 2019 to Jun 2022, the general information of patients and the epidemiological characteristics such as the proportion of different strains and clinical infection were analyzed by WHONET software. Results A total of 16 285 mold infection cases were included in the analysis, of which 49.3% were patients aged 61 and over, with the median age of 60 years old. The proportion of males was significantly higher than that of females (62.1% vs. 37.9%). The patients were mainly from the internal medicine, ICU and surgical wards. Most strains were isolated from lower respiratory tract, accounting for 81.7%, followed by pus and secretions (7.8%). In terms of species distribution, Aspergillus spp. accounted for the highest proportion (84.8%), with Penicillium spp., Fusarium spp., order Mucorales and Sedosporium spp. accounting for 5.1%, 3.0%, 1.3% and 0.4%, respectively. For species distribution among different mold infection, 88.7% of lower respiratory tract mold infections were caused by Aspergillus spp., and Aspergillus fumigatus(47.8%) was the most common species. Otomycosis was mainly caused by Aspergillus spp.(98.7%), of which Aspergillus terreus accounted for 39.7%, and ophthalmomycosis was mainly caused by Fusarium spp.(54.6%). Conclusions By the retrospective analysis of mold isolation from multicenter in China, we found that Aspergillus fumigatus, Aspergillus terreus, and Fusarium spp. were the most common species causing pneumonomycosis, otomycosis, and ophthalmomycosis, respectively. Therefore, it is necessary to pay attention to the differences in species distribution among different mold infections in clinical empirical treatment of fungal infections.

Antimicrobial resistance poses a significant threat to global public health, especially for Enterobacterales. In this study, we investigated the distribution and antimicrobial resistance of Enterobacterales in children in the China Antimicrobial Surveillance Network (CHINET) in 2015–2021. In total, 81,681 strains isolated from children were collected in this period, accounting for 50.1% of Gram-negative organisms. The most frequently isolated Enterobacterales were Escherichia coli, Klebsiella spp., Salmonella spp., and Enterobacter spp. The main sources of the isolates were urine and the respiratory tract, accounting for 29.3% and 27.7% of isolates, respectively. The proportions of E. coli, Klebsiella pneumoniae, and Proteus mirabilis expressing extended-spectrum β-lactamase were 48.8%–57.6%, 49.3%–66.7%, and 23.1%–33.8%, respectively. The prevalence of carbapenem-resistant Enterobacterales was 5.7%–9.5%, which showed a decreasing trend from 2015 to 2021. The detection rates of carbapenem-resistant Klebsiella spp., carbapenem-resistant Enterobacter spp., and carbapenem-resistant E. coli were 14.1%–22.6%, 7.1%–15.7% and 2.0%–3.4%, respectively. In Enterobacterales, the resistance rates to ciprofloxacin were higher than to levofloxacin. However, the Enterobacterales strains were highly susceptible to amikacin, polymyxin B, and tigecycline. The resistance rate of Salmonella spp. to ampicillin was > 70%, whereas their resistance rate to ceftriaxone was < 30%. These findings indicate that the resistant rates of some Enterobacterales isolates in children to common antimicrobial agents show decreasing trends. Continuous monitoring of bacterial resistance should be strengthened to prevent and control the spread of drug-resistant bacteria. [ABSTRACT FROM AUTHOR]

Urinary tract infections (UTIs) are common urological diseases that easily relapse and have led to an increasing economic and health burdens. The China Antimicrobial Surveillance Network (CHINET) system is one of the most influential antimicrobial resistance surveillance networks in China. This study analyzed antimicrobial resistance and distribution trends of uropathogens from 2015 to 2021 using the CHINET system. A total of 261,893 non-duplicate strains were collected; Gram-positive bacteria accounted for 23.8% while Gram-negative bacteria accounted for 76.2%. Escherichia coli, Enterococcus faecium, Klebsiella pneumoniae, and Enterococcus faecalis were the most common species. The resistance to vancomycin, linezolid, and teicoplanin in E. faecalis and E. faecium was less than 3%. The prevalence of carbapenem-resistant strains of E. coli, K. pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii was 1.7%, 18.5%, 16.4%, and 40.3%, respectively. The prevalence of carbapenem-resistant A. baumannii increased from 27.6% in 2015 to 43.4% in 2021. The prevalence of methicillin-resistant Staphylococcus aureus decreased from 40.6% in 2015 to 22.9% in 2021. The resistance rates to most β-lactam antimicrobials, aminoglycosides and fluoroquinolones in E. coli, K. pneumoniae, P. aeruginosa and A. baumannii isolated from ICU inpatients were significantly higher than in those isolated from outpatients and non-ICU inpatients. This study indicates that E. coli, Enterococcus, and K. pneumoniae were the most commonly isolated uropathogens in China. The bacterial species isolated and their antimicrobial resistance patterns differed in different patient populations. More attention must be paid uropathogen resistance surveillance to provide data for the rational use of antimicrobial agents. [ABSTRACT FROM AUTHOR]

Carbapenem-resistant Salmonella has recently aroused increasing attention. In this study, a total of four sequence type 36 Salmonella enterica subsp. enterica serovar Typhimurium (S. Typhimurium) isolates were consecutively isolated from an 11-month-old female patient with a gastrointestinal infection, of which one was sensitive to carbapenems and three were resistant to carbapenems. Via antibiotic susceptibility testing, a carbapenemases screening test, plasmid conjugation experiments, Illumina short-reads, and PacBio HiFi sequencing, we found that all four S. Typhimurium isolates contained a blaCTX-M-14-positive IncI1 plasmid. One carbapenem-sensitive S. Typhimurium isolate then obtained an IncHI2 plasmid carrying blaNDM-1 and an IncP plasmid without any resistance genes during the disease progression. The blaNDM-1 gene was located on a new 30 kb multiple drug resistance region, which is flanked by IS26 and TnAs2, respectively. In addition, the ST_F0903R isolate contained eight tandem copies of the ISCR1 unit (ISCR1-dsbD-trpF-ble-blaNDM-1-ISAba125Δ1), but an increase in MICs to carbapenems was not observed. Our work further provided evidence of the rapid spread and amplification of blaNDM-1 through plasmid. Prompting the recognition of carbapenem-resistant Enterobacterales and the initiation of appropriate infection control measures are essential to avoid the spread of these organisms. [ABSTRACT FROM AUTHOR]

Objectives: To determine the epidemiological cut-off values (ECOFFs) of norvancomycin for Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus and Staphylococcus hominis.Methods: We collected 1199 clinical isolates of Staphylococcus species from five laboratories located in four cities in China. MICs and inhibitory zone diameters of norvancomycin were determined by broth microdilution and the disc diffusion method, separately. ECOFFs of norvancomycin for four species were calculated by ECOFFinder software following EUCAST principles. Methicillin and vancomycin resistance genes (mecA/mecC and vanA/vanB/vanC/vanD/vanE) were screened for by PCR in all isolates. Pearson correlation and χ2 test were used to calculate the correlation of MICs and inhibition zone diameters, and MICs and resistance genes, respectively.Results: MICs of norvancomycin for all strains from five laboratories fell in the range of 0.12-2 mg/L. ECOFFs of norvancomycin were determined to be 2 mg/L for S. epidermidis and S. haemolyticus and 1 mg/L for S. aureus and S. hominis. A weak correlation was observed between MIC values and zone diameters for S. haemolyticus (r = -0.36) and S. hominis (r = -0.26), while no correlation was found for S. epidermidis and S. aureus. The mecA gene was detected in 63.1% of Staphylococcus, whereas no isolate carried mecC, vanA, vanB, vanC, vanD or vanE. ECOFFs of norvancomycin were not correlated with mecA gene carriage in Staphylococcus species.Conclusions: ECOFFs of norvancomycin for four Staphylococcus species were determined, which will be helpful to differentiate WT strains. The correlation of MICs and zone diameters of norvancomycin was weak in Staphylococcus species. [ABSTRACT FROM AUTHOR]