Objective:To understand the awareness of influenza and influenza vaccine, influenza incidence, influenza vaccination status and intention and related factors in primary and secondary school teachers.Methods:Cross-sectional study design and stratified random sampling method were used to select 5 teachers from each of 51 primary schools and 40 middle schools in a district of Beijing from April 17 to 21, 2024. A questionnaire survey was conducted in the selected teachers with an estimated sample size of 1 040. The survey collected the information about their demographic characteristics, awareness of influenza and influenza vaccine, influenza incidence, influenza vaccination status and intention. Multivariate logistic regression model was used to analyze the factors related to influenza vaccination status and intention.Results:In the 975 primary and secondary school teachers, the awareness of susceptibility and severity of influenza and the benefits of influenza vaccination were high. In terms of safety of influenza vaccine, 48.00% (468/975) of the teachers believed that adverse reaction would occur after the vaccination. Influenza like illness occurred in 41.13% (401/975) of the teachers during 2023-2024, and in these teachers, 40.15% (161/401) asked for leave from work due to illness, 40.90% (164/401) sought medical care and 32.93% (54/164) were influenza virus positive. In the 975 teachers, 13.95% (136/975) were vaccinated against influenza during 2023-2024 and 34.46% (336/975) were willing to be vaccinated against influenza during 2024-2025. Multivariate logistic regression analysis showed that being teacher in charge of a class (a OR=1.58, 95% CI: 1.06-2.35), believing that influenza vaccination could effectively prevent influenza (a OR=1.99, 95% CI: 1.05-3.80), believing that teachers' vaccination could improve students' willingness to be vaccinated (a OR=1.98, 95% CI: 1.12-3.50) were the positive factors for teachers' vaccination, and worrying about adverse reactions after the vaccination (a OR=0.52, 95% CI: 0.34-0.80) was the negative factor. Doctors' recommendation (a OR=2.62, 95% CI: 1.41-4.86) and free influenza vaccination (a OR=10.26, 95% CI: 5.17-20.39) were positively correlated with teachers' intention to influenza vaccination. Conclusions:Primary and secondary school teachers in a district of Beijing had high awareness of influenza and influenza vaccine, but their awareness of influenza vaccine safety should be improved. The incidence of influenza-related infection was high in the primary and secondary school teachers. The influenza vaccination rate was low and the willingness to receive influenza vaccination in following year was not strong. For the better prevention and control of influenza in schools, it is necessary to strengthen the health education in primary and secondary school teachers to improve their awareness of influenza vaccine safety and vaccination rate.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.

Objective:To report the nationwide surveillance results of pathogenic profiles and antimicrobial resistance patterns of Gram-positive bloodstream infections in China in 2023.Methods:The clinical isolates of Gram-posttive bacteria from blood cultures were collected in member hospitals of National Bloodstream Infection Bacterial Resistant Investigation Collaborative System（BRICS）during January to December 2023. Antimicrobial susceptibility testing was performed using the dilution method recommended by the Clinical and Laboratory Standards Institute（CLSI）. Statistical analyses were conducted using WHONET 5.6 and SPSS 25.0 software.Results:A total of 4 385 Gram-positive bacterial isolates were obtained from 60 participating center. The top five pathogens were Staphylococcus aureus（ n=1 544，35.2%），coagulase-negative Staphylococci（ n=1 441，32.9%）， Enterococcus faecium（ n=574，13.1%）， Enterococcus faecalis（ n=385，8.8%），and α-hemolytic Streptococci（ n=187，4.3%）. The prevalence of methicillin-resistant Staphylococcus aureus（MRSA）and methicillin-resistant coagulase-negative Staphylococci（MRCNS）was 26.2%（405/1 544）and 69.8%（1 006/1 441），respectively. Notably，all Staphylococci remained susceptible to glycopeptide or daptomycin. Staphylococcus aureus demonstrated excellent susceptibility（>97.0%）to cephalobiol，rifampicin，trimethoprim-sulfamethoxazole，linezolid，minocycline，tigecycline，and eravacycline. No Enterococcus exhibiting resistance to linezolid were detected. Glycopeptide resistance was uncommon but more frequent in Enterococcus faecium（resistance to vancomycin and teicoplanin：both 1.7%）compared to Enterococcus faecalis（both 0.3%）. The detection rates of MRSA and MRCNS exhibited significant regional variations across the country（ χ2=17.674 and 148.650，respectively，both P<0.001）. No vancomycin-resistant Enterococci were detected in central China. Institutional comparison demonstrated higher prevalence of MRSA（ χ2=14.111， P<0.001）and MRCNS（ χ2=4.828， P=0.028）in provincial hospitals than that in municipal hospitals. Socioeconomic analysis identified elevated detection rates of both MRSA（ χ2=18.986， P<0.001）and MRCNS（ χ2=4.477， P=0.034）in less developed regions（per capita GDP

Objective:To report the results of bacterial resistant investigation collaborative system（BRICS）on the distribution and antimicrobial resistance profile of clinical Gram-negative bacteria isolates from bloodstream infections in China in 2023，and provide reference for clinical tretment of bloodstream infections and prevention and control of bacterial resistance.Methods:The clinical isolates of Gram-negative bacteria from blood cultures in member hospitals of BRICS were collected during January 2023 to December 2023. Antibiotic susceptibility tests were conducted by agar dilution or broth dilution methods recommended by Clinical and Laboratory Standards Institute（CLSI）. WHONET 5.6 and SPSS 25.0 were used to analyze the data.Results:During the study period，11 492 strains of Gram-negative bacteria were collected from 60 hospitals，of which 10 098（87.9%）were Enterobacterales and 1 394（12.1%）were non-fermentative bacteria. The top 5 bacterial species were Escherichia coli（50.0%）， Klebsiella pneumoniae（26.1%）， Pseudomonas aeruginosa（5.1%）， Acinetobacter baumannii complex（5.0%）and Enterobacter cloacae complex（4.1%）. The ESBL-producing rates in Escherichia coli， Klebsiella pneumoniae and Proteus mirablilis were 46.8%（2 685/5 741），18.3%（549/2 999）and 44.0%（77/175），respectively. The prevalence of carbapenem-resistant Escherichia coli（CREC）and carbapenem-resistant Klebsiella pneumoniae（CRKP）were 1.3%（76/5 741）and 15.0%（450/2 999）；32.9%（25/76）and 78.0%（351/450）of CREC and CRKP were sensitive to ceftazidime/avibactam combination，respectively. 94.7%（72/76）and 90.2%（406/450）of CREC and CRKP were sensitive to aztreonam/avibactam combination. Furthermore，57.9%（44/76）and 79.1%（356/450）were sensitive to imipenem/relebactam combination. The prevalence of carbapenem-resistant Acinetobacter baumannii（CRAB）complex was 64.6%（370/573），while more than 80.0% of CRAB complex was sensitive to tigecycline，eravacycline and polymyxin B. The prevalence of carbapenem-resistant Pseudomonas aeruginosa（CRPA）was 17.0%（99/581）. There were differences in the composition ratio of Gram-negative bacteria in bloodstream infections and the prevalence of important Gram-negative bacteria resistance among different regions in China，with statistically significant differences in the prevalence of CREC，CRKP，CRPA and CRAB complex（ χ2=10.6，28.6，10.8 and 19.3， P<0.05）. The prevalence of ESBL-producing Escherichia coli， CREC，CRAB complex and CRKP were higher in provincial hospitals than those in municipal hospitals（ χ2=12.5，9.8，12.7 and 57.8，all P<0.01）. Conclusions:Gram-negative bacteria are the main pathogens causing bloodstream infections in China，and Escherichia coli is ranked in the top，while the trend of Klebsiella pneumoniae increases continuously with time. CRKP infection shows a slow upward trend，CREC infecton maintains a low prevalence level，and CRAB complex infection continues to exhibit a high prevalence rate. The composition and resistance patterns of pathogens causing bloodstream infections vary to some extent across different regions and levels of hospitals in China.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective:To explore the factors that tend to lead to a low normal fertilization rate in spindle transfer of mouse oocytes and its strategies.Methods:Oocytes in metaphase Ⅱ (MⅡ) of C57BL/6 and ICR strains mouse were obtained for observations of mitochondrial replacement operations. Spindle karyoplasts of three different sizes (large, medium, small) were isolated by micromanipulation, and their morphology was observed under bright field and polarized light at 0 min, 10 min, 20 min and 30 min after suction. For small spindle karyoplasts, 2% paraformaldehyde fixation was performed after 10 min, 20 min and 30 min respectively, and the morphology of spindle and chromosomes was observed after immunofluorescence staining. Intracytoplasmic sperm injection (ICSI) was performed on oocytes, followed by small spindle karyoplasts isolation, and then fusion was conducted after 30 min (traditional method), 10 min (modified method 1) and 0 min (modified method 2) respectively. ICSI-oocytes without spindle transfer were used as control group, and 14-16 h later, the fertilization of reconstructed oocytes was observed and statistically analyzed.Results:1) When spindle karyoplast was just retrieved (0 min), the karyoplast membrane was smooth and complete, and the spindle showed a normal spindle shape. After 10 min, 20 min and 30 min of suction, the karyoplast membrane was twisted or elongated with an irregular morphology, and the spindle was also twisted, stretched or scattered with a weaker brightness. And the smaller spindle karyoplast, the more serious the deformation was. 2) When the spindle was just taken out (0 min), immunofluorescence staining showed that the spindle was in a standard spindle shape, and the chromosomes were regularly and neatly arranged on the equatorial plate. With the prolongation of placement time, spindles were elongated and tapered or dumbbell-shaped, and chromosomes were scattered and irregularly arranged. 3) For the traditional method of spindle transfer, the normal fertilization rate of C57BL/6 mouse reconstructed oocytes was 63.16% (24/38), which was statistically different from that of control group ( P=0.002). The normal fertilization rate [68.00% (34/50)] in the modified method 1 group was significantly lower than that in control group [90.00% (36/40), P=0.019], but there was no statistical difference with the traditional method ( P=0.260). However, the normal fertilization rate [82.50% (33/40)] in the modified method 2 group was similar to control group ( P=0.422), and was significantly higher than that of the traditional method group ( P=0.010). Conclusion:The longer the spindle karyoplast of mouse oocytes is stayed after retrieval, the more serious the morphological changes, the more unstable the spindles and chromosomes, and the lower normal fertilization rate. Immediate fusion of spindle karyoplast after isolation is the best time for mitochondrial replacement micromanipulation.

Objective:To understand the awareness of influenza and influenza vaccine, influenza incidence, influenza vaccination status and intention and related factors in primary and secondary school teachers.Methods:Cross-sectional study design and stratified random sampling method were used to select 5 teachers from each of 51 primary schools and 40 middle schools in a district of Beijing from April 17 to 21, 2024. A questionnaire survey was conducted in the selected teachers with an estimated sample size of 1 040. The survey collected the information about their demographic characteristics, awareness of influenza and influenza vaccine, influenza incidence, influenza vaccination status and intention. Multivariate logistic regression model was used to analyze the factors related to influenza vaccination status and intention.Results:In the 975 primary and secondary school teachers, the awareness of susceptibility and severity of influenza and the benefits of influenza vaccination were high. In terms of safety of influenza vaccine, 48.00% (468/975) of the teachers believed that adverse reaction would occur after the vaccination. Influenza like illness occurred in 41.13% (401/975) of the teachers during 2023-2024, and in these teachers, 40.15% (161/401) asked for leave from work due to illness, 40.90% (164/401) sought medical care and 32.93% (54/164) were influenza virus positive. In the 975 teachers, 13.95% (136/975) were vaccinated against influenza during 2023-2024 and 34.46% (336/975) were willing to be vaccinated against influenza during 2024-2025. Multivariate logistic regression analysis showed that being teacher in charge of a class (a OR=1.58, 95% CI: 1.06-2.35), believing that influenza vaccination could effectively prevent influenza (a OR=1.99, 95% CI: 1.05-3.80), believing that teachers' vaccination could improve students' willingness to be vaccinated (a OR=1.98, 95% CI: 1.12-3.50) were the positive factors for teachers' vaccination, and worrying about adverse reactions after the vaccination (a OR=0.52, 95% CI: 0.34-0.80) was the negative factor. Doctors' recommendation (a OR=2.62, 95% CI: 1.41-4.86) and free influenza vaccination (a OR=10.26, 95% CI: 5.17-20.39) were positively correlated with teachers' intention to influenza vaccination. Conclusions:Primary and secondary school teachers in a district of Beijing had high awareness of influenza and influenza vaccine, but their awareness of influenza vaccine safety should be improved. The incidence of influenza-related infection was high in the primary and secondary school teachers. The influenza vaccination rate was low and the willingness to receive influenza vaccination in following year was not strong. For the better prevention and control of influenza in schools, it is necessary to strengthen the health education in primary and secondary school teachers to improve their awareness of influenza vaccine safety and vaccination rate.

Objective:To assess the precision of various automated antimicrobial susceptibility testing systems for ciprofloxacin, levofloxacin, piperacillin/tazobactam, amikacin, gentamicin and tobramycin before and after the update of the breakpoints by Clinical and Laboratory Standards Institute.Methods:A total of 65 strains of Enterobacterales (34 Escherichia coli and 31 Klebsiella pneumoniae) and 33 strains of Pseudomonas aeruginosa were collected from Peking University People′s Hospital, Sichuan Provincial People′s Hospital, and the First Affiliated Hospital of Sun Yat-sen University in 2023. Broth microdilution (BMD) was employed as the reference method to assess the accuracy of ten antimicrobial susceptibility panels (NMIC-413, GN09, N335, NMIC45, GN4F, NMIC-150, DL-120E, DL-120NE, ONE-96 and NF-96) in seven automated antimicrobial susceptibility testing systems currently utilized in China. Results:Except for the GN-09, N-335, and NMIC-150, there were breakpoints that were not covered for the minimum inhibitory concentrations reported by the other panels in the validation. There was no very major error (VME) in the verification results except for the cases of not covered. Among the 65 strains of Enterobacterales, the essential agreement rate (EA%) of ciprofloxacin and levofloxacin was higher than 92.3% (60/65), and the categorical agreement rate (CA%) of ciprofloxacin using the new breakpoint decreased from 100% (65/65)-98.5% (64/65) to 95.4% (62/65)-86.2% (56/65). The major error rate (ME%) of N-335 card increased from 1.5% (1/65) to 4.6% (3/65); except for GN-09 and N-335 cards, the CA% of other cards under new breakpoint was ≥96.9% (63/65) with no ME; the EA% of piperacillin/tazobactam was ≥93.8% (61/65), and the CA% under new breakpoint was ≥92.3% (60/65), and the ME% of N-335 card increased from 1.5% (1/65) to 4.6% (3/65). The EA% and CA% under new breakpoint of amikacin, gentamicin and tobramycin were all ≥ 96.9% (63/65) with no ME. Among the 33 tested Pseudomonas aeruginosa isolates, the EA% of ciprofloxacin was ≥93.8% (30/32), and after applying the new breakpoints, the CA% of ciprofloxacin decreased from 90.6% (29/32)-100% (33/33) to 84.4% (27/32)-100% (33/33). On the NMIC-413 card, 2 strains showed ME. For levofloxacin, the EA% was ≥90.9% (30/33), and the CA% of the new breakpoint interpretation decreasing from 90.6% (29/32)-100% to 69.7% (23/33)-93.8% (30/32), with no ME. For amikacin and tobramycin, the EA% was ≥93.8% (30/32), and on most panels, the CA% of new breakpoints for amikacin and tobramycin were ≥96.9% (31/32).Conclusions:At present, the breakpoints cannot be covered by the panels in many automated antimicrobial sensitivity testing systems in China. Ciprofloxacin and levofloxacin did not meet the validation requirements for Enterobacterales and Pseudomonas aeruginosa in most antimicrobial susceptibility testing systems. After the breakpoints updated, it is essential to validate the automated antimicrobial susceptibility system for clinical application.

Objective To investigate the antimicrobial resistance of clinical isolates from elderly patients(≥65 years)in major medical institutions across China.Methods Bacterial strains were isolated from elderly patients in 52 hospitals participating in the CHINET Antimicrobial Resistance Surveillance Program during the period from 2015 to 2021.Antimicrobial susceptibility test was carried out by disk diffusion method and automated systems according to the same CHINET protocol.The data were interpreted in accordance with the breakpoints recommended by the Clinical and Laboratory Standards Institute(CLSI)in 2021.Results A total of 514 715 nonduplicate clinical isolates were collected from elderly patients in 52 hospitals from January 1,2015 to December 31,2021.The number of isolates accounted for 34.3％of the total number of clinical isolates from all patients.Overall,21.8％of the 514 715 strains were gram-positive bacteria,and 78.2％were gram-negative bacteria.Majority(90.9％)of the strains were isolated from inpatients.About 42.9％of the strains were isolated from respiratory specimens,and 22.9％were isolated from urine.More than half(60.7％)of the strains were isolated from male patients,and 39.3％isolated from females.About 51.1％of the strains were isolated from patients aged 65-＜75 years.The prevalence of methicillin-resistant strains(MRSA)was 38.8％in 32 190 strains of Staphylococcus aureus.No vancomycin-or linezolid-resistant strains were found.The resistance rate of E.faecalis to most antibiotics was significantly lower than that of Enterococcus faecium,but a few vancomycin-resistant strains(0.2％,1.5％)and linezolid-resistant strains(3.4％,0.3％)were found in E.faecalis and E.faecium.The prevalence of penicillin-susceptible S.pneumoniae(PSSP),penicillin-intermediate S.pneumoniae(PISP),and penicillin-resistant S.pneumoniae(PRSP)was 94.3％,4.0％,and 1.7％in nonmeningitis S.pneumoniae isolates.The resistance rates of Klebsiella spp.(Klebsiella pneumoniae 93.2％)to imipenem and meropenem were 20.9％and 22.3％,respectively.Other Enterobacterales species were highly sensitive to carbapenem antibiotics.Only 1.7％-7.8％of other Enterobacterales strains were resistant to carbapenems.The resistance rates of Acinetobacter spp.(Acinetobacter baumannii 90.6％)to imipenem and meropenem were 68.4％and 70.6％respectively,while 28.5％and 24.3％of P.aeruginosa strains were resistant to imipenem and meropenem,respectively.Conclusions The number of clinical isolates from elderly patients is increasing year by year,especially in the 65-＜75 age group.Respiratory tract isolates were more prevalent in male elderly patients,and urinary tract isolates were more prevalent in female elderly patients.Klebsiella isolates were increasingly resistant to multiple antimicrobial agents,especially carbapenems.Antimicrobial resistance surveillance is helpful for accurate empirical antimicrobial therapy in elderly patients.

Objective To examine the changing prevalence and antimicrobial resistance profiles of Burkholderia cepacia in 52 hospitals across China from 2015 to 2021.Methods A total of 9 261 strains of B.cepacia were collected from 52 hospitals between January 1,2015 and December 31,2021.Antimicrobial susceptibility of the strains was tested using Kirby-Bauer method or automated antimicrobial susceptibility testing systems according to a unified protocol.The results were interpreted according to the breakpoints released in the Clinical & Laboratory Standards Institute(CLSI)guidelines(2023 edition).Results A total of 9 261 strains of B.cepacia were isolated from all age groups,especially elderly patients.The proportion was 11.1％(1 032 strains)in children,significantly lower than the proportion in adults.About half(46.5％,4 310/9 261)of the strains were isolated from patients at least 60 years old and 42.3％(3 919/9 261)of the strains were isolated from young adults.Most isolates(71.1％)were isolated from sputum and respiratory secretions,followed by urine(10.7％)and blood samples(8.1％).B.cepacia isolates were highly susceptible to the five antimicrobial agents recommended in the CLSI M100 document(33rd edition,2023).B.cepacia isolates showed relatively higher resistance rates to meropenem and levofloxacin.However,the resistance rates to ceftazidime,trimethoprim-sulfamethoxazole,and minocycline remained below 8.1％.The percentage of B.cepacia strains resistant to levofloxacin was the highest compared to other antibiotics in any of the three age groups(from 12.4％in the patients＜18 years old to 20.6％in the patients aged 60 years or older).Conclusions B.cepacia is one of the clinically important non-fermenting gram-negative bacteria.Accurate and timely reporting of antimicrobial susceptibility test results and ongoing antimicrobial resistance surveillance are helpful for rational prescription of antimicrobial agents and proper prevention and control of nosocomial infections.