Abstract:Since the outbreak of COVID-19, it has spread to more than 160 countries, causing a pandemic worldwide, bringing a huge impact on the global medical system and causing huge economic losses. The genome of SARS-CoV-2 is constantly mutating, with higher immune escape ability and stronger infectivity, and the infected people tend to have mild symptoms, which brings greater challenge to epidemic prevention and control. The epidemic prevention and control in China has gone through four stages and achieved remarkable results, which proves the advanced and scientific nature of Chinese epidemic prevention and control mode. Rapid and powerful pathogen detection capabilities as well as rapid and precise epidemiological investigation capabilities are the magic weapons for the effective control of COVID-19 in China. In medical institutions, especially in designated hospitals for COVID-19, timely, efficient and standardized epidemiological investigation is the key to the prevention and control of COVID-19 in hospital. Precise epidemiological investigation is the premise and basis for the implementation of hierarchical management and control of epidemic-related populations and epidemic-related areas in the hospital, and is the gua rantee to prevent the spread of epidemic in hospital and prevent the non-combat reduction of medical personnel. Com pared with the epidemiological investigation of the social aspect, epidemiological investigation of COVID-19 epidemic in hospital has its particularity, it is necessary to conduct a more precise epidemiological investigation in a small area, not only prevent the spread of the epidemic, but also meet the medical needs of patients as much as possible. How to carry out epidemiological investigation of the epidemic in the hospital (in key areas) will form a new topic of epidemic prevention and control. In the hospital prevention and control of COVID-19, Xiangya Hospital of Central South University has always insisted on completing the epidemiological investigation of COVID-19 with its own strength under the guidance of the Center for Disease Control and Prevention, forming a Xiangya mode of in-hospital epidemiological investigation. This article introduces the significance, methods and investigators of COVID-19 in-hospital epidemiological investigation, as well as the challenge and prospect of healthcare-associated infection under the new situation based on Xiangya's experience in epidemiological investigations in hospitals.

Abstract:Objective To understand the respiratory system function and health status of patients with coronavirus disease 2019 (COVID-19) after discharge from hospital. Methods COVID-19 patients who admitted to Wuhan Lei Shen Shan Hospital from February to March 2020 were divided into two groups (common group and severe group) according to The diagnosis and treatment protocol for COVID-19 (trial version 7). The general data of patients, baseline clinical characteristics such as smoking history, past history and exercise status, scores of modified Medical Research Council (mMRC), results of 6-minute walking test (6MWT), as well as chest CT findings and scores at discharge were collected. Patients were followed up at 6, 12, 18 and 24 months after discharge, and were inquired whether they still had clinical symptoms of COVID-19. Results 320 patients with COVID-19 were included in the study, 179 (55.9%) in common group and 141 (44.1%) in severe group; 149 (46.6%) were males and 171 (53.4%) were females. Fatigue and sleep disturbance were the most common clinical symptoms at post-discharge follow-up visits, compared with discharge, these symptoms were significantly improved 12 months after discharge(P < 0.05). The 6-minute walking distance (6MWD) of patients in common group was significantly improved at 6 months after discharge, and patients in severe group was significantly improved at 12 months after discharge (both P < 0.05). The most common abnormal manifestations of chest CT were ground glass shadow and fibrosis, by the end of 24 months after discharge, 94.1% (178/185)of the patients had completely absorbed the chest CT lesions. Cox regression analysis showed that independent protective factors for complete absorption of abnormal chest CT findings in COVID-19 patients were as follows: younger age (HR=0.975, 95%CI: 0.963-0.987, P < 0.001), lower disease severity (common/severe group, HR=1.800, 95%CI: 1.255-2.581, P=0.001), higher level exercise (moderate activity/fluctuation, HR=1.432, 95%CI: 1.046-1.961, P=0.025), higher absolute value of baseline lymphocytes (HR=1.126, 95%CI: 1.054-1.202, P < 0.001), and low baseline C-reactive protein level (HR=0.991, 95%CI: 0.982-0.999, P=0.036). Conclusion Most common and severe types of COVID-19 patients recover well at 24-month follow-up, and the recovery of respiratory system function is faster in common group than severe group. Younger age, higher level of physical activity, lower disease severity, higher baseline lymphocyte level and lower baseline C-reactive protein level are all conducive to the complete absorption of lesions shown by chest CT.

Abstract:Objective To evaluate the effect of setting up full-time healthcare-associated infection (HAI) control staff for implementing on-site supervision in the buffer room of isolation ward. Methods The first-line health care workers (HCWs) who participated in anti-coronavirus disease 2019 (COVID-19) in Zhangjiajie People's Hospital from August to September 2021 were selected as the survey objects, questionnaire about general information, the psychological status of the first-line HCWs after full-time HAI control staff implementing supervision, and effect evaluation after the implementation of supervision by full-time HAI control staff were made, Questionnaire Star was used for survey. Results A total of 227 valid questionnaires were collected. 78.9% of HCWs thought that the on-site supervision of full-time HAI control staff made them feel more secure; 94.7% of HCWs thought that their fear and anxiety had been alleviated in varying degrees; 93.0% of HCWs felt at ease in the first undressing room; 99.6% of HCWs were willing to accept the deficiencies pointed out by full-time HAI control staff on the spot and needed the supervision of full-time HAI control staff; 93.8% of HCWs thought that the environment was better than before; 82.8% of HCWs thought that full-time HAI control staff could prevent the occurrence of non-standard manipulation in time; 98.7% of HCWs thought that in case of emergency, HAI full-time control staff could give correct guidance and help; most HCWs thought that full-time HAI control staff could help them to wear and take off protective clothing. Conclusion The implementation of on-site supervision by HAI full-time staff is conducive to relieving the pressure of first-line HCWs, improving the environment and providing timely help and guidance. In the process of supervision, attention should be paid to women and first-line HCWs who participated in the fight against the epidemic for the first time.

Abstract:Objective To understand the occurrence of healthcare-associated infection (HAI) in patients with coronavirus disease 2019 (COVID-19) caused by Delta variant of SARS-CoV-2, and provide reference for the prevention and control of HAI in COVID-19 treatment hospitals. Methods Through the combination of medical record reviewing and bedside checking, HAI of all patients in a COVID-19 designated hospital on January 13, 2022 were investigated and analyzed by adoping the time point prevalence survey method. Results A total of 403 COVID-19 patients were investigated, ranging in age from 10 months to 94 years, with a median age of 36 years, the case preva-lence rate of HAI was 1.99%. There were significant differences in the prevalence rate of HAI among patients with COVID-19 at different ages, disease types as well as diagnosis and treatment location (all P < 0.05). The utilization rate of ventilator was 1.24%, 2 patients had ventilator-associated pneumonia; utilization rate of urinary catheter was 1.99%, 1 patient had catheter-associated urinary tract infection; utilization rate of central venous catheterization was 0.99%, and no patient had central venous catheter-related bloodstream infection. The main infection site was lower respiratory tract, the main pathogen was Staphylococcus aureus. Antimicrobial use rate was 1.74%, all were therapeutic and monotherapy. Conclusion With the continuous evolution and variation of SARS-CoV-2, epidemic situation in many countries and regions has rebounded, the prevalence of HAI in patients with COVID-19 caused by Delta variant is lower than that of patients with COVID-19 caused by the original strain, and there are some differences in the use of antimicrobial agents and invasive operation; the elderly, severe patients and intensive care unit patients are the groups that COVID-19 designated hospitals should focus on to prevent and control HAI.

Abstract:Objective To analyze the characteristics of hand hygiene (HH) compliance of staff in medical institutions (MIs) during the epidemic period of coronavirus disease 2019 (COVID-19), and put forward evidence-based intervention policies for improving HH compliance. Methods Relevant literatures on HH compliance of staff in MIs during the epidemic period of COVID-19 were retrieved from PubMed, Embase, Cochrane Library, Web of Science, China National Knowledge Infrastructure (CNKI), Wanfang Data, VIP and China Biology Medicine disc (CBMdisc) in January 2020-October 2021, two researchers independently screened the literature, extracted data and evaluated the quality, Meta-analysis was conducted with DerSimonian and Laird models. Results A total of 10 literatures on HH compliance involving 2 377 staff in MIs were included in this study. The overall HH compliance during the COVID-19 epidemic period was 74% (95%CI: 68%-79%). Subgroup analysis results showed HH compliance rates of staff of different professions in hospitals from high to low were nurses, doctors and other employees, which were 80% (95%CI: 74%-87%), 76% (95%CI: 71%-81%) and 70% (95%CI: 62%-77%) respectively. Staff in MIs had the highest HH compliance (91%, 95%CI: 88%-94%) after contact with patient body fluid, while the lowest HH compliance (68%, 95%CI: 62%-74%) before contact with patient. Conclusion During the epidemic period of COVID-19, HH compliance of staff in MIs has been greatly improved. Auxiliary personnel are the key personnel to improve HH compliance, before contacting patients is the key moment of HH compliance intervention.

Abstract:Objective To explore the changes and correlation between bone mineral density and migration ability of bone marrow mesenchymal stem cells (BMSCs) in patients with spinal tuberculosis. Methods From June 1, 2020 to December 1, 2021, 72 patients with spinal tuberculosis underwent spinal internal fixation (tuberculosis group) and 76 patients with thoracolumbar fracture or spinal stenosis underwent spinal internal fixation (control group) in a hospital were selected, bone mineral density of patients was determined, BMSCs were extracted from blood in screw path of 6 patients in tuberculosis group and control group respectively, the extracted BMSCs were cultured simply and co-cultured with BCG (BCG was added to BMSCs for co-culture), the migration rates of BMSCs at the 8th, 16th and 24th hours in each group was measured by scratch test, difference of migration ability of BMSCs in each group was compared, correlation between bone mineral density and migration rate of BMSCs was analyzed. Results Bone mineral density ([0.84±0.19] g/cm²) in tuberculosis group was lower than that in control group ([0.95±0.16] g/cm²), difference was significant (P < 0.05); migration rate of BMSCs in tuberculosis group was lower than that in control group (P < 0.05); after co-culture with BCG, the migration ability of BMSCs in tuberculosis group still significantly decreased (P < 0.05). The correlation coefficient (r value) between migration rate of BMSCs and vertebral bone mineral density at the 8th and 16th hours were 0.80 and 0.67 respectively. Conclusion Compared with patients with thoracolumbar fracture or spinal stenosis, bone mineral density of patients with spinal tuberculosis is significantly lower, migration ability of BMSCs of patients with spinal tuberculosis is weakened; BCG has no significant effect on the migration ability of BMSCs, and bone mineral density is positively correlated with migration rate of BMSCs.

Abstract:Objective To explore the value of FilmArray meningitis/encephalitis (FA ME) panel and metageno-mics next-generation sequencing (mNGS) in pathogenic diagnosis of central nervous system (CNS) infection. Methods Cerebrospinal fluid (CSF) specimens from 29 patients with suspected CNS infection in the Third Affiliated Hospital of Sun Yat-sen University between June 2020 and January 2021 were collected for FA ME panel detection and mNGS, combined with bacterial/fungal culture and viral nucleic acid/serological detection results, effects of FA ME and mNGS in the pathogenic diagnosis of CNS infection were compared. Results The positive rates of FA ME and mNGS were 7.1% and 9.1% respectively, which were slightly higher than 3.4% of bacterial culture, there was no significant difference (P=1.000). In terms of fungi, positive rates of FA ME and mNGS were 10.7% and 13.6% respectively, which were both lower than those in fungal culture (17.2%), difference was significant (P=0.003). The positive rates of virus detected by FA ME and mNGS were 3.6% and 18.2% respectively, which were higher than those detected by nucleic acid/serology in hospital (0). Conclusion FA ME and mNGS are not enough to replace the current routine detection in hospital, but may be used as an adjunctive tool to improve the detection level of CNS infection pathogens.

Abstract:Objective To understand the implementation situation of prevention and control of catheter-related bloodstream infection (CRBSI) in second-level and above medical institutions in a province, so as to provide refe-rence for medical institutions to take effective measures to implement the best evidence and reduce CRBSI. Methods Questionnaire was designed base on Guideline for prevention and control of vascular catheter-related infection (2021 version), current situation of prevention and control of CRBSI in second-level and above medical institutions in a province in July 2021 was investigated. Results A total of 87 questionnaires were collected and 79 (90.8%) were available. Monitoring work (89.9%) as well as formulation of prevention and control system (94.9%) for CRBSI in 79 medical institutions were basically implemented, but the system update was lagging behind, only 78.7% of them were updated. 68.4% of the hospitals paid attention to the incidence of CRBSI in the past three years, and few hospitals paid attention to the incidence of central venous catheter (CVC), peripherally-inserted central venous catheter (PICC) and dialysis catheter-related infection, with the lowest rate of 38.9%. Pre-catheterization evaluation (100%) and sterile manipulation technology of operator during catheterization (≥97.5%) were well implemented. There were four weak points in the implementation of CRBSI prevention and control guidelines: only 3.8% of hospitals used disinfectant containing chlorhexidine concentration >0.5% for skin disinfection, 54.4% of hospitals failed to pull out catheter within 2 days when emergency catheterization could not ensure effective aseptic operation technique, 43.0% of hospitals performed catheterization in wards, and 43.0% of hospitals failed to replace additional devices within 4 hours after using catheter blood transfusion; 26.6% of hospitals indicated that intensive care unit was the department with the highest incidence of CRBSI. Conclusion At present, there is a certain gap between the implementation of prevention and control measures for CRBSI in clinical practice and the guidelines, it is recommended that medical personnel strengthen their understanding of the best practice standards, implement infection prevention and control in accordance with the guidelines, and minimize the risk of CRBSI.

Abstract:Objective To investigate the effect of protective stoma on organ space infection (OSI) in patients with rectal cancer after low anterior rectal resection (Dixon operation). Methods Post-operative OSI of rectal cancer patients who underwent Dixon operation in a hospital from 2017 to 2021 was monitored prospectively, risk factors for infection were analyzed, according to the distance from tumor to anal margin, patients were divided into three groups: ≥7 cm, 5-7 cm and < 5 cm groups, proportion of protective stoma and infection of each group, as well as infection rates of patients with and without protective stoma were compared. Results From 2017 to 2021, OSI rate in rectal cancer patients undergoing Dixon operation was 4.79% (51/1 064). Risk factors analysis showed that male, pre-operative anemia, pre-operative intestinal obstruction, drainage time>10 days, distance from tumor to anus < 7 cm, operation duration >3 hours were independent risk factors for OSI, and protective stoma was the independent protective factor for OSI. Patients with the distance from tumor to anus ≥7 cm had the lowest post-operative infection rate (2.76%); patients with the distance of 5-7 cm had the highest post-operative infection rate (9.52%); patients with the distance < 5 cm had the highest proportion of protective stoma (72.05%). For patients with distance from tumor to anus ≥7 cm, protective stoma can not effectively prevent the occurrence of infection, while for patients whose distance was < 5 cm, protective stoma can significantly reduce the infection rate, difference was significant (P=0.02); infection rate of patients with 5-7 cm from tumor to anus after protective stoma also decreased significantly, but difference was not significant (P=0.07). Conclusion Protective stoma has protective effect on OSI in rectal cancer patients after Dixon operation, especially in patients whose distance from tumor to anus is less than 5 cm.

Abstract:Objective To explore the effect of integrated pre-and in-hospital management on reducing the incidence of aspiration and hypostatic pneumonia in patients with acute ischemic stroke(AIS). Methods 108 AIS patients who were diagnosed and treated in a hospital from March 2020 to October 2021 were selected as the research objects, according to the different intervention time and management modes, 55 AIS patients who received routine nursing operation in the hospital from March to December 2020 were as control group, and 53 AIS patients who received integrated pre-and in-hospital management from January to October 2021 were as intervention group, incidence of aspiration and hypostatic pneumonia, average hospitalization time, patient satisfaction of two groups of AIS patients, as well as scores in the examination of infection prevention and control, airway management knowledge, compliance rate of hand hygiene of doctors and nurses in two patients' groups were compared. Results Incidences of aspiration and hypostatic pneumonia in AIS patients in intervention group were 9.43% and 3.77% respectively, which were both lower than those in control group (25.45% and 14.55% respectively); the average hospitalization time of intervention group was shorter than that of control group ([10.79±5.35] days vs ([13.69±6.84] days), patients' satisfaction was higher than that of control group (96.23% vs 81.82%) (all P < 0.05). The scores of knowledge on healthcare-associated infection (HAI) prevention and control, airway management as well as hand hygiene compliance rate of doctors and nurses in patients' intervention group were higher than those in control group (all P < 0.001). Conclusion Early intervention in AIS patients with integrated pre-and in-hospital management mode can reduce the incidence of aspiration and hypostatic pneumonia, effectively shorten hospitalization time of patients, improve the satisfaction of patients, enhance the awareness of infection prevention and control of health care workers, and improve prevention and control level of HAI, which is worthy of clinical promotion and application.

Abstract:Objective To evaluate the clinical characteristics and prognosis of community-acquired carbapenem-resistant Klebsiella pneumoniae (CRKP) bloodstream infection. Methods Klebsiella pneumoniae bloodstream infection cases in a hospital from February 2017 to March 2021 were analyzed retrospectively, according to antimicrobial susceptibility testing results, they were divided into carbapenem resistance group (CRKP group) and carba-penem susceptibility group (CSKP group), clinical characteristics and 30-day prognosis of two groups of patients were compared. Results There were significant differences between two groups of patients in terms of coronary heart disease or heart failure, chronic obstructive pulmonary disease, recent hospitalization history, chronic renal insufficiency, anemia, deep vein catheterization, mechanical ventilation, indwelling gastric tube, and urinary catheterization, CRKP group was higher than CSKP group (all P < 0.05). The 30-day mortality in CRKP group was higher than that in CSKP group (58.82% vs 9.68% P < 0.001). Conclusion Community-acquired CRKP bloodstream infection accounts for a high proportion of patients with cardiopulmonary and renal underlying diseases as well as recent hospitalization history, prognosis of CRKP group is poor, which should be paid clinical attention.

Abstract:Objective To explore risk factors for ventilator-associated pneumonia (VAP) following cardiac surgery in adults. Methods Medical records of adult patients undergoing cardiac surgery through sternotomy in a hospital between January 2017 to May 2021 were collected retrospectively. Patients with VAP after surgery were selected as case group, case-control matching was conducted according to 1 ∶1 matching. Univariate and multivariate logistic regression analysis were performed for the risk factors of VAP. Results A total of 5 919 cardiac surgery adult patients used ventilators after operation, 766 of whom used ventilator for more than 48 hours. 62 patients had VAP, incidence was 1.05%, 8.03 cases/1 000 mechanical ventilation days, and 61 cases were successfully matched. Multivariate analysis showed that pre-operative creatinine≥1.1 mg/dL, duration of operation≥7.33 hours and post-operative disturbance of consciousness were independent risk factors for VAP after cardiac surgery in adults. The pathogen of infection was mainly Gram-negative bacteria (54 strains, 90.0%), Acinetobacter baumannii had the highest isolation rate (24 strains, 40.0%). The risk for gastrointestinal hemorrhage, nasogastric tubing and acute kidney injury in VAP patients significantly increased, and the length of ICU stay, hospitalization cost and mortality significantly increased (all P < 0.01). Conclusion Improving renal function before operation, shortening duration of surgery and reducing post-operative disturbance of consciousness can reduce the incidence of VAP after cardiac surgery in adults.

Abstract:Objective To explore the application value of double culture method in improving the detection rate of smear-negative Mycobacterium. Methods The screened specimens of patients with the initial diagnosis in a hospital from January 2019 to September 2021 were collected and grouped according to solid culture, liquid culture and solid-liquid double culture. In addition, patients with smear-negative Mycobacterium, positive solid, positive liquid or positive solid-liquid double culture were selected, they were divided into pulmonary Mycobacterium (PM) group and extrapulmonary Mycobacterium (EPM) group according to specimen sites, clinical characteristics of two groups of patients were analyzed. Results A total of 6 492 smear-negative patients were surveyed, 3 234 were in solid group, 1 938 in liquid group and 1 320 in double culture group, 253 patients (3.90%) were positive for culture, positive culture detection rates of patients in solid culture, liquid culture and solid-liquid double culture group were 2.35% (n=76), 4.54% (n=88) and 6.74% (n=89) respectively; detection rates of PM were 3.11%, 6.02% and 7.13% respectively, detection rates of EPM were 1.02%, 2.68% and 6.09% respectively. Among 253 smear-negative but culture positive patients, 143 were male and 110 were female; the mean age was (58.34±18.47) years; the median detection time were 34.65, 10.45 and 9.89 days respectively. Among patients in PM group, the proportion of male patients, cough and expectoration, underlying respiratory diseases, inflammatory exudation showed on chest CT, positive results of tuberculosis T cell spot test were all higher than EPM group, differences were all significant (all P < 0.05). Positive detection rate of EPM of solid-liquid double culture group was higher than solid and liquid groups (both P < 0.001), positive detection rate of PM in solid-liquid double culture group was higher than solid culture group (P < 0.001). Conclusion Patients with PM have the characteristics of cough and expectoration, respiratory diseases, inflammatory exudation on chest CT, while patients with EPM have no typical characteristics. Clinical signs of EPM are more concealed than that of PM, and it is easy to miss diagnosis, solid-liquid double culture method can improve the detection rate of Mycobacterium in optimizing the sample pre-treatment and workflow.

Abstract:Tropheryma whipplei (TW) is a kind of Gram-positive bacterium, which belongs to fastidious bacteria and is often difficult to be diagnosed clinically. Whipple's disease is a chronic multi-system infectious disease caused by TW, the common target organs are gastrointestinal tract and joint, pulmonary involvement is rare. This paper reports that the clinical manifestations of the patient are fever, cough and dyspnea, CT finding shows bilateral lungs diffuse ground glass shadow. Metagenomic sequencing of bronchoalveolar lavage fluid shows mixed infection of TW and Candida tropicalis infection. The patient's condition is improved after treated with meropenem, compound sulfamethoxazole, and fluconazole. This paper reports a case of TW pneumonia and reviews the literatures, so as to improve the clinical understanding of TW infection, achieve early diagnosis and treatment.

Abstract:Since the emergence of the SARS-CoV-2 Omicron variant in November 2021, it has rapidly swept the world in a few months. Many countries in the world have witnessed a new round of epidemics with Omicron as the main epidemic strain, and some cities in China, such as Hong Kong, Shenzhen and Shanghai, have not been spared. Omicron spike protein contains a large number of mutations and has strong immune escape ability, which poses a great threat to the existing vaccines and antibody-related therapy. Although disease symptoms caused by Omicron variant are mild, the global health system is under great pressure due to its high transmission rate. In this paper, the pathogenic characteristics, variation sources, transmission characteristics, epidemic status and control measures of Omicron variant are reviewed, so as to provide reference for scientific control.

Abstract:With the normalization of epidemic prevention and control, the use of personal protective equipment (PPE) tends to become more and more common, meanwhile, due to the high incidence of headache associated with PPE (HAPPE), it has gradually become one of the hotspots of many studies. Combined with the recent relevant research, this paper discusses the pathogenesis, related influencing factors and intervention measures of HAPPE, so as to provide reference for the formulation of intervention plan for HAPPE among health care workers.