Surgical site infection(SSI)is a significant type of hospital-associated infection,with varying incidence rates across different regions and surgical procedures.SSI not only increases the burden on the healthcare system but also poses serious threats to patient safety and quality of life.China has established a multi-level and multi-di-mensional management framework,including laws,industry standards and guidelines,to regulate prevention and control behaviors through various documents such as the"Measures for the Management of Hospital-associated In-fection"and the"Technical Guidelines for the Prevention and Control of Surgical Site Infection".In recent years,with the development of international and domestic cooperation,the formulation of professional guidelines and consensuses and the implementation of evidence-based research,China has achieved certain results in SSI preven-tion and control.However,problems such as differences in awareness and implementation across regions,inade-quate data sharing and integration and lack of long-term follow-up still exist.In the future,it is necessary to create an AI-assisted personalized prevention and control model,establish an interdisciplinary collaborative prevention and control system and promote the implementation of administrative management and professionalization to con-tinuously optimize the SSI prevention and control system and improve medical quality and patient safety.

OBJECTIVE To investigate the direct economic losses caused by surgical site infection(SSI)in patients undergoing orthopedic surgery and provide references for medical institutions to develop infection prevention and control measures.METHODS Clinical data of 8 207 patients undergoing orthopedic surgery from the People's Hospital of Sanshui District,Foshan City,between 2021 and 2023 were retrospectively collected.Among them,98 patients with SSI were assigned to the SSI group,while non-infected patients were included in the non-infection group.Based on a 1∶1 matched case-control principle,68 well-matched pairs of case-control samples were select-ed for comparative analysis.Key indicators such as hospitalization costs and postoperative hospital stays were de-scribed as medians,and intergroup differences were analyzed with the Wilcoxon signed-rank test.RESULTS The SSI incidence rate was 1.19％(98/8 207).Compared to non-infected patients,those with SSI had an average pro-longed postoperative hospital stay of 13.95 days,with an average direct economic loss of RMB 14 305.50 yuan per case.Direct economic losses due to SSI varied among patients with different surgical sites,age groups and wheth-er medical devices were implanted.There were statistically significant differences in the increased hospitalization costs and postoperative hospital stays between the SSI group and the non-infected group(P＜0.05).CONCLUSIONS SSI in patients undergoing orthopedic surgery leads to increased hospitalization costs,prolonged postoperative hospital stays and greater direct economic losses.Therefore,medical institutions should implement a series of efficient and targeted prevention and control measures to effectively reduce SSI incidence rate,there-by improve medical quality and patient safety.

OBJECTIVE To analyze the characteristics of global surgical site infection(SSI)outbreaks and provide references for targeted prevention and control measures.METHODS SSI outbreak events from Jan.1,1990 to Dec.31,2023 were searched from Wanfang Med,CNKI,VIP and PubMed.Data on department distribution dur-ing the outbreak,duration,investigation methods,main causes,transmission modes,pathogen composition and outbreak outcomes were summarized for analysis.RESULTS A total of 111 SSI outbreaks in 20 countries were identi-fied,involving 1 382 patients and 24 deaths.The source of the outbreak was identified in 78 cases,mainly involving med-ical personnel in 27 cases(34.62％),hospital equipment in 19 cases(24.36％),environmental factors in 11 cases(14.10％),workflow factors in 10 cases(12.82％),hospital water factors in 7 cases(8.97％)and disinfectant fac-tors in 4 cases(5.13％).The duration of SSI outbreaks abroad was 5.00(1.50,12.00)months,longer than that in China[1.00(1.00,2.00)month](P＜0.05).In China,the outbreaks mainly occurred in neurosurgery,cardiac surger-y,orthopedics,obstetrics and general surgery,while at abroad,they mainly occurred in cardiac surgery,orthopedics,and involved multiple surgical departments.Environmental hygiene methods were adopted in up to 90.63％of cases in China.Compared with China,analytical epidemiological methods and molecular epidemiological methods were more com-monly used abroad.Targeted measures and strengthened basic measures were implemented for different outbreak sources to terminate the SSI outbreaks.Pulsed-field gel electrophoresis(34 times)was a widely used molecular typing method in outbreak investigations.CONCLUSIONS Based on the analysis of SSI outbreak characteristics and risk factors,it is neces-sary to strengthen medical personnel training and monitoring of special pathogens.At the same time,the epidemiologi-cal investigation capabilities of infection control professionals should be strengthened.

OBJECTIVE To explore the time windows for postoperative pneumonia in patients undergoing different surgeries,providing evidence-based references for optimizing infection monitoring and prevention and control strategies.METHODS Sociodemographic characteristics,clinical information and surgical details of 263 patients with postoperative pneumonia from four different types of medical institutions between Jan.2019 and Dec.2024 were retrospectively collected.The time windows for postoperative pneumonia in patients undergoing different surgeries were analyzed.RESULTS There were no statistically significant differences in the time windows for post-operative pneumonia among groups in terms of sociodemographic factors and underlying diseases.However,sta-tistically significant differences were observed in the time windows for postoperative pneumonia based on surgery type,incision type,surgical approach and surgery duration(P＜0.05).The average time for the onset of postop-erative pneumonia in 263 patients was 2.00(1.00,7.00)days.The postoperative time windows varied for sur-geries involving different systems.The peak incidence occurred on day 0(16 cases)and day 1(17 cases)af-ter neurological surgery,while the peak incidence for digestive system and orthopedic surgeries was on day 1.The time span for the onset of pneumonia after skin surgeries was wider(0-53 days postoperatively)without a clear peak.In addition,33.33％of cardiovascular system surgery cases developed pneumonia 10 days postoperatively.There were also significant time differences in the diagnostic elements of postoperative pneumonia,with fever and abnormal white blood cell counts appearing earlier(median appearance time length:4.00 days)than lung imaging changes(median appearance time length:7.00 days).CONCLUSIONS This study demonstrates significant time differences in the on-set of postoperative pneumonia and confirms the significant spatiotemporal heterogeneity in the diagnostic elements of postoperative pneumonia.These findings provide a quantitative basis for developing dynamic,surgery-type-spe-cific monitoring protocols and prevention and control measures for postoperative pneumonia.

OBJECTIVE To analyze the biological characteristics and genomic features of highly lytic bacteriopha-ges isolated from sewage in tropical hospitals and provide references for the hospital-associated infection prevention and control of multidrug-resistant Acinetobacter baumannii(MDR-Ab).METHODS With MDR-Ab as the host bacterium,bacteriophages were isolated from sewage.Transmission electron microscopy was employed to observe their morphology,and determine the optimal multiplicity of infection(MOI),one-step growth curve and environ-mental stability.Whole-genome sequencing and bioinformatics analysis were conducted to annotate functional genes and construct a phylogenetic tree.RESULTS A virulent bacteriophage,HN_Aba_01,was isolated.Elec-tron microscopy revealed that it belonged to the Myoviridae family,with a head diameter of 50 nm and a tail length of 90 nm.This bacteriophage exhibited strong lytic activity,with an optimal MOI of 0.000 000 1,a latent period of 5 minutes and a lysis yield of 15 PFU/cell.It remained stable at temperatures ranging from 4 ℃ to 60 ℃and pH values from 3 to 10.Genomic analysis identified 85 ORFs,including lyase,perforin and depolymerase genes.It shared 98.12％identity with the bacteriophage AbP2 genome(reference genome)and was classified into the Obolenskvirus genus.CONCLUSIONS The bacteriophage isolated from tropical hospital sewage,with high lyt-ic activity and good environmental adaptability,can be used for the hospital-associated infection prevention and control of MDR-Ab.

OBJECTIVE To investigate the current status of monitoring indicators related to the"Perioperative In-fection Control"in medical institutions above the secondary level in Guizhou Province,and to delve into the imple-mentation of key measures for infection prevention and control during the perioperative period for patients under-going surgical operations.METHODS Based on the"Implementation Plan for the'Perioperative Infection Control'Initiative in Guizhou Province",a"Case Investigation Form on Key Measures for Infection Prevention and Control During the Perioperative Period for Patients Undergoing Surgical Operation"was developed.A total of 138 medi-cal institutions participated in the case investigation,and a total of 2 128 cases were investigated.RESULTS The overall monitoring indicators for the"Perioperative Infection Control"initiative in the 138 medical institutions a-bove the secondary level in Guizhou Province were at a relatively low level.The skin cleansing compliance rate was 80.32％,the hair removal compliance rate was 16.43％,the prophylactic antibacterial drug administration rate within 0.5-1 hour before surgery was 55.94％and the antibacterial drug discontinuation rate within 24 hours after prophylactic medication for type Ⅰ incision surgeries was 56.48％.The hair removal compliance rate was higher in tertiary medical institutions(19.21％)than in secondary medical institutions(14.34％)(P=0.039).The distri-bution of the four monitoring indicators varied in clinical departments and surgery types,with statistically signifi-cant differences(P＜0.05).The preferred method for surgical site skin cleansing in medical institutions across the province was local wiping,primarily with clean water(57.21％).The primary method for hair removal was razors(68.82％),and hair removal on the day of surgery was most common(61.75％).CONCLUSIONS Conduc-ting a survey on the current status of"Perioperative Infection Control"initiative monitoring indicators in medi-cal institutions in Guizhou Province helps to understand the implementation of key measures for perioperative in-fection prevention and control and set intervention targets,thus providing references for establishing a dynam-ic monitoring indicator change mechanism.

OBJECTIVE To conduct continuous targeted surveillance on patients undergoing pancreatoduodenecto-my in a three-A comprehensive hospital,to understand the current status of postoperative surgical site infection(SSI),identify risk factors and provide references for effective prevention and control measures.METHODS A targeted surveillance of SSI was conducted on 812 patients who underwent open pancreatoduodenectomy in the General Surgery Department of Qilu Hospital of Shandong University from 2020 to 2023.Statistical analysis was performed on various indicators,the incidence rate of SSI.RESULTS There were 42 cases of SSI in patients under-going pancreatoduodenectomy,with an incidence rate of 5.17％.Among them,there were 2 cases of deep surgi-cal incision infection and 40 cases of organ(or lacuna)infection.There was no statistically significant difference in the incidence rate of SSI across different years,but there was a decreasing trend over the years(P=0.227).Mul-tivariate logistic regression analysis showed that incision cleanliness(contamination)and intraoperative blood loss(＞250 ml)were risk factors for SSI,while the tumor location(pancreas)was a protective factor for SSI(P＜0.05).The surgeon-specific infection incidence rate ranged from 0.00％to 20.00％,with the highest infection rate observed in Surgeon No.1(20.00％).After adjustment,the top three surgeons with the highest specific in-fection rates were Surgeon No.1(50.00％),Surgeon No.5(34.49％)and Surgeon No.20(32.05％).Among the samples from 42 patients with SSI,70 pathogenic bacteria were detected,mainly Escherichia coli(18.57％)and Enterococcus faecium(14.29％).The hospital stay for patients with SSI after surgery was 25.00(20.00,34.00)days,while the hospital stay for patients without SSI was 19.00(16.00,24.00)days.Patients had an ex-tended hospital stay of 6 days due to SSI(P＜0.001).CONCLUSIONS SSI in patients undergoing pancreatoduode-nectomy is mainly organ(or lacuna)infection.Incision cleanliness(contamination)and intraoperative blood loss(＞250 ml)can increase the incidence rate of SSI in patients undergoing pancreatoduodenectomy.The specific in-fection rates vary among different surgeons,with the main pathogenic bacteria causing SSI being E.coli and E.faecium.The occurrence of SSI prolongs patients'hospital stay.

OBJECTIVE To analyze the pathogenic characteristics and clinical features of patients with invasive pul-monary aspergillosis(IPA)and summarize the risk factors for poor prognosis.METHODS The clinical data of 89 patients diagnosed with IPA based on microbial identification of Aspergillus from sputum or bronchoalveolar lav-age fluid cultures and diagnostic criteria,who were admitted to Zhongda Hospital Southeast University from Aug.2022 to Jul.2024 and were queried by electronic case system,were analyzed retrospectively.The distribu-tion of Aspergillus pathogens and clinical features of patients with IPA were analyzed,and the risk factors for poor prognosis were summarized.RESULTS A total of 107 Aspergillus strains were isolated from 89 cases,including 55 strains of Aspergillus fumigatus(51.40％),30 strains of Aspergillus flavus(28.04％)and 10 strains of As-pergillus niger(9.34％).There were 63 m ale patients(70.79％),and 34 cases had poor prognosis.Baseline pe-ripheral blood lymphocyte count(＜0.645×109)(OR=6.653,95％CI:2.013-21.990,P=0.002)and ICU admission(OR=8.303,95％CI:1.283-53.741,P=0.026)were identified as risk factors for poor prognosis in patients with IPA.Receiver operating characteristic curve analysis showed that the cut-off point for baseline pe-ripheral blood lymphocyte count in predicting prognosis in patients with IPA was 0.645 ×109/L,with a sensitivity of 85.22％and a specificity of 69.67％.CONCLUSIONS Baseline peripheral blood lymphocyte count and ICU ad-mission are risk factors for poor prognosis in patients with IPA.The alert value for baseline peripheral blood lym-phocyte count is 0.645 × 109/L,which has good predictive value for the occurrence of poor prognosis.

OBJECTIVE To explore the diagnostic value of the guanylate binding protein 5(GBP5)gene in pa-tients infected with Mycobacterium tuberculosis(MTB).METHODS Patients who visited the Fifth People's Hos-pital of Suzhou from Jan.2024 to May 2024,as well as individuals undergoing health examinations during the same period,were selected as the study subjects.Based on the diagnostic criteria,the subjects were divided into active tuberculosis(ATB)group(230 cases),pneumonia group(207 cases),latent tuberculosis infection(LTBI)group(48 cases)and healthy control(HC)group(122 cases).Real-time quantitative reverse transcription poly-merase chain reaction was used to detect the expression level of the GBP 5 gene in the whole blood of the subjects,and receiver operating characteristic(ROC)curves were employed to analyze its diagnostic performance.RESULTS There were statistically significant differences in GBP5 gene expression among the four groups(P＜0.001).The area under the ROC curve(AUC)for GBP5 in distinguishing the ATB group from the HC group,LTBI group and pneumonia group was 0.902,0.813 and 0.745,respectively.In the ATB group,the positive de-tection rate of the GBP5 method was 67.39％,higher than that of Gene Xpert MTB/RIF(62.20％),tuberculosis culture(60.00％)and smear acid-fast staining(35.20％)(P＜0.05).When distinguishing between ATB and LTBI patients,the positive prediction value of GBP5 was 95.09％,higher than that of IGRA testing(79.92％)(P＜0.05).The expression level of GBP5 was negatively correlated with the MTB bacterial load(P＜0.001).CONCLUSIONS The detection of the GBP5 gene has important clinical significance in the auxiliary diagno-sis of tuberculosis and can serve as an effective supplement to existing diagnostic methods for tuberculosis.

OBJECTIVE To evaluate the efficacy of sulbactam-durlobactam combined with meropenem in treating carbapenem-resistant Acinetobacter baumannii(CRAB)pulmonary infection.METHODS A total of 16 patients treated at China-Japan Friendship Hospital from Jan.1,2025 to Jun.1,2025 were included.Retrospective analy-sis was conducted on patients'basic situation,preliminary treatment regimens,infection-related diagnoses,etiolo-gy and clinical outcomes.Therapeutic drug monitoring(TDM)for sulbactam was also performed.RESULTS By the end of the treatment course,13 patients achieved etiological eradication of CRAB and clinical improvement,while 1 patient experienced CRAB recurrence within one month.Three patients showed treatment failure.TDM for sulbactam was performed in 13 patients.Except for one slightly lower,all achieved trough plasma concentra-tions above the minimum inhibitory concentration(MIC)(100％T＞MIC,MIC=4 mg/L based on clinical breakpoints).Dosage adjustments based on plasma concentrations were made for 4 patients,with 3 receiving re-duced doses and 1 receiving an increased dose.CONCLUSIONS Sulbactam-durlobactam combined with meropenem demonstrates superior efficacy in treating CRAB compared to other regimens.Under the recommended dosage,all patients can achieve the PK/PD target for sulbactam.