Abstract:Objective To establish a field experimental research method to evaluate air transmission ability of respiratory infectious diseases. Methods The simulated saliva containing Escherichia coli phage was atomized in a typical mechanical ventilation ward, atomized droplets and cough droplets had droplet spectrum of similar droplet size distribution, the number of droplet nuclei with different particle size in air was detected, geometrical dimension of the initial droplet was estimated, the number of phages initially carried by droplet nuclei was calculated, the actual survival of phages in the droplet nuclei was obtained by collecting biological specimen of air, survival function of phage carried by droplet nuclei in ward air between two groups of data was compared. Results The number of viable phages carried by simulated atomized saliva droplets rapidly lost about 83% under surface evaporation, the average survival function of phage in the droplet nuclei was stable at 17% and did not change with the detection point during the detection period of 360 seconds, attenuation rate of the number of droplet nuclei in indoor air was consistent with that of phages in air specimens, biological exposure level of the ward space can be calculated by recording the number of atomized droplet nuclei. Conclusion The artificial simulation technology of virus transmission in the air induced by cough droplet nuclei can be applied to evaluate field experiment of the air transmission ability of respiratory infectious diseases.

Abstract:Objective To construct and evaluate the quality assessment index system of healthcare-associated infection(HAI) in the hospital performance assessment system. Methods HAI quality assessment index system was preliminary designed, HAI quality assessment index in hospital performance assessment system was determined through two rounds of Delphi expert consultation and analytic hierarchy process. Results A set of HAI quality assessment system was constructed, including 2 first-class indexes, 9 second-class indexes and 38 third-class indexes, positive coefficient of two rounds of Delphi expert consultation was 100%, authority coefficient was 0.826 and 0.852 respectively; coordination coefficient of the second round was relatively low, and expert opinions tended to be consistent. The top five indexes of combination weight of second-class indexes were infection-related indicator (0.204), infection safety (0.155), infection assessment (0.110), disinfection and sterilization (0.109), and hand hygiene (0.103). The top five indexes of combination weight of third-class indexes were antimicrobial use in infected patients (0.052), preoperative antimicrobial use (0.048), implementation of hand hygiene indication (0.045), grasp of infection knowledge (0.044), and HAI rate (0.042). The reliability and validity test showed that Cronbach's α coefficient of the index system was 0.788, r values of retest reliability and structural validity were both >5, difference were both significant (both P<0.05). Conclusion HAI quality assessment index system constructed in this study can evaluate HAI management performance fairly and objectively.

Abstract:Objective To explore the application of diagnosis-related groups(DRGs) index system in the management of healthcare-associated infection(HAI). Methods DRGs-related indexes, including HAI information, DRG grouping, and case mixed index(CMI) of discharged patients in the intensive care unit (ICU) of a hospital from April to November 2018 were collected, incidence of HAI was adjusted through CMI, incidence of infection in ICU before and after adjustment was compared, DRGs with more infected patients in each ICU was determined, HAI prevention and control measures were put forward. Results Before CMI adjustment, incidence of HAI was the highest in neurosurgical ICU (38.78%) and lowest in neonatal ICU (5.14%); after CMI adjustment, incidence of HAI was the highest in general ICU (12.37%) and lowest in emergency ICU (2.11%). There were 14 DRGs in the top three of discharged patients with HAI in each ICU, accounting for 7.37% of all DRGs; there were 198 cases of HAI in patients in 14 DRGs, accounting for 57.89% of all HAI patients. Conclusion DRGs index system helps to compare and analyze the incidence of different types of HAI as well as HAI in different hospitals, which provides a new idea for HAI management.

Abstract:Objective To investigate the distribution and antimicrobial resistance of pathogens causing early infection in patients after lung transplantation(within 3 months) in a respiratory intensive care unit (RICU), so as to provide evidence for empirical antimicrobial treatment of early infection after lung transplantation. Methods Clinical and pathogenic data of patients with lung transplantation time<3 months in RICU of a hospital from September 2017 to September 2018 were collected, pathogens and antimicrobial resistance were statistically analyzed. Results A total of 134 patients were included in study, 349 strains of pathogens were isolated, Gram-negative bacteria accounted for 91.12%, 91.04% of which were mixed infection cases with more than 2 species of strains. The top three pathogens were Acinetobacter baumannii, Klebsiella pneumoniae, and Pseudomonas aeruginosa, accounting for 29.51%, 16.05%, and 15.47% respectively. Specimens were mainly from sputum (81.09%) and bronchoalveolar lavage fluid (12.89%). Resistance rate of Acinetobacter baumannii to polymyxin B was 2.91%, and resistance rates to other antimicrobial agents were 56.31%-100.00%. Resistance rates of Klebsiella pneumoniae to polymyxin B and imipenem were 3.57% and 69.64% respectively. Pseudomonas aeruginosa was sensitive to tobramycin,amikacin, gentamicin, piperacillin/tazobactam, ciprofloxacin, and levofloxacin, resistance rates were 1.85%-14.81%, polymyxin B-resistant strains were not found. Resistance rates of Stenotrophomonas maltophilia to levofloxacin, compound sulfamethoxazole and ceftazidime were all low (8.70%-28.26%). Isolation rate of methicillin-resistant Staphylococcus aureus (MRSA) was 95.24%, vancomycin- and linezolid-resistant Staphylococcus aureus strain was not found. Conclusion Gram-negative bacteria are the main pathogens causing early infection in patients after lung transplantation in RICU, the proportion of mixed infection is high. Antimicrobial resistance rates of different strains are varied, isolation rates of carbapenem-resistant Acinetobacter baumannii and carbapenem-resistant Klebsiella pneumoniae are higher, which should be paid more attention in clinic.

Abstract:Objective To analyze the epidemiological characteristics and incidence trend of scarlet fever in Zhangjiagang City from 2005 to 2018, so as to provide basis for prevention of scarlet fever outbreak. Methods Data of scarlet fever cases reported by Zhangjiagang Infectious Disease Reporting Information Management System from 2005 to 2018 were analyzed retrospectively, control chart of epidemic was used to predict the incidence trend of scarlet fever from February to June 2019. Results From 2005 to 2018, 584 cases of scarlet fever were reported in Zhangjiagang City, with an average annual incidence of 2.64/100 000, and there was no death case. From 2005 to 2010, the reported incidence was in a slow and steady stage, with an average annual incidence of 1.04/100 000; from 2011 to 2018, incidence of reported cases was in a rising stage, annual incidence was 3.85/100 000, the reported cases increased obviously. The ratio of incidence of male to female was 1.58:1, 3-12-year-old group had the highest incidence, accounting for 95.21% (556/584). The main reporting units of scarlet fever were tertiary medical institutions, accounting for 85.96% (502/584). Seasonal distribution of scarlet fever was obvious, incidence of scarlet fever was high in April-June each year and November to January of next year, it is predicted that incidence of scarlet fever would be maintained at a high level in February-June of 2019. Conclusion Incidence of scarlet fever in Zhangjiagang City is in an increased trend from 2011 to 2018, 3-12-year-old is the main group. According to the incidence trend from 2011 to 2018, it is predicted that February to June 2019 will be the peak stage of scarlet fever in Zhangjiagang City, prevention and control measures of scarlet fever in kindergartens, schools and crowded places should be strengthened, diagnostic sensitivity of medical institutions needs to be improved, so as to prevent the outbreak of scarlet fever.

Abstract:Objective To evaluate and summarize nursing management strategies for the prevention and control of coronavirus disease 2019 (COVID-19) based on Vincent clinical event analysis model. Methods Evidence in domestic and foreign database was searched comprehensively, including guidelines, evidence summary, best practice, expert consensus and systematic reviews, quality of the included literatures was evaluated by AGREE Ⅱ score, AMSTAR 2 score standard, as well as JBI checklist for text and opinion (2016 Edition). Results A total of 26 literatures were included, all of which were expert consensus. 50 pieces of optimal evidence were summarized from 6 dimensions. Conclusion Conversion and application of evidence related to the nursing management strategies for the prevention and control of COVID-19 should be combined with the current situation of hospital and the number of confirmed and suspected cases,so as to to select optimal evidence for reducing the incidence and mortality of COVID-19.

Abstract:Objective To explore the application value of severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) nucleic acid test in different population, including persons in fever clinic and isolation wards, susceptible persons as well as persons in large-scale screening, provide reference for laboratory nucleic acid test of SARS-CoV-2. Methods Laryngeal swabs from different population in People's Hospital of Zhengzhou between February 1, 2020 and March 22, 2020 were collected, including patients in fever clinic and isolation wards, anti-epidemic front-line health care workers(HCWs), hospitalized patients without symptoms of coronavirus disease 2019 (COVID-19), accompanying family members, and persons returning to work. Real-time reverse transcriptase-polymerase chain reaction(RT-PCR) and two domestic detection kits A and B were used to test SARS-CoV-2 nucleic acid in patients in fever clinic and isolation wards. Results A total of 15 497 laryngeal swabs were detected, 24 of which were positive for SARS-CoV-2 nucleic acid test, nucleic acid test positive cases were all from fever clinic and isolation wards. 24 cases of SARS-CoV-2 nucleic acid test positive laryngeal swabs were all negative for blood specimens tested at the same time. The first laryngeal swab test results of kits A and B were identical, re-test of 2 confirmed cases after treatment were positive in kit A group and negative in kit B group. Nucleic acid test results were all negative in front-line HCWs, hospitalized patients without COVID-19 symptoms, accompanying family members and physical examination persons returning to work. Conclusion No positive results are found in the screening among the returning workers, hospitalized patients, accompanying family members and front-line epidemic prevention and control professionals, positive rate of SARS-CoV-2 nucleic acid of laryngeal swab specimens is higher than that of blood specimens, positive rates of different nucleic acid test reagents are slightly different.

Abstract:Objective To investigate the core emergency response competence(CERC) of health care workers (HCWs) in Chongqing in the face of coronavirus disease 2019(COVID-19), and analyze the influence factors for emergency response competence in the face of COVID-19. Methods Convenient sampling method was adopted, questionnaire was designed according to HCWs' CERC system for infectious diseases, HCWs' CERC for COVID-19 in Chongqing was investigated and analyzed. Results A total of 725 valid questionnaires of HCWs were collected, score of CERC for COVID-19 was (128.14±25.38), multiple linear regression analysis showed the main influencing factors for CERC of HCWs were age,professional qualifications,job categories, hospital level,whether departments ever attended the training related to COVID-19. Conclusion HCWs' CERC for COVID-19 in Chongqing is at intermediate-level, training should be conducted according to different age,professional qualifications, job categories and departments, emergency drilling needs to be strengthened, so as to improve HCWs' CERC in the face of infectious disease emergent event.

Abstract:Objective To observe the application effect of completely covered sputum storage cup in the management of expectoration of patients with coronavirus diseas 2019(COVID-19). Methods 36 patients with COVID-19 were randomly divided into trial group and control group according to convenient sampling method, 18 cases in each group, trial group used completely covered sputum storage cup, control group used conventional sputum storage cup, incidence of sputum exposure and expectoration feeling of patients as well as use impression of nurses between two groups were compared. Results Incidence of sputum exposure in trial group was lower than that in control group (5.56% vs 66.67%), satisfaction rate of expectoration feeling in patients in trial group was higher than that in control group (94.44% vs 61.11%). Satisfaction rate of 22 nurses impression after they used two kinds of cups in trial group and control group were 100.00% and 50.00% respectively. There were significant differences in the incidence of sputum exposure, expectoration feeling of patients and nurses impression after they used two kinds of cups between two groups (all P<0.05). Conclusion Completely covered sputum storage cup can reduce sputum exposure of patients with COVID-19, improve the comfort of patients and impression of nurses, reduce incidence of occupational exposure of health care workers.

Abstract:Objective To explore the relationship between human immunodeficiency virus (HIV) infection and onset risk of heart failure(HF). Methods PubMed, Embase, Chinese Biomedical Literature Database, China National Knowledge Infrastructure(CNKI), Wanfang Database, and VIP Database were searched,the published prospective cohort studies on HIV infection and onset risk of HF were collected, Meta-analysis was conducted with Stata 12.0 software, pooled hazard ratio (HR) and corresponding 95% confidence interval(CI) was calculated. Results Five studies were included, 84 557 were in HIV infection exposed group and 219 177 in non-HIV infection exposed group. Meta-analysis showed that HIV infection may increase the onset risk of HF by 48%(HR=1.48,95%CI:1.31-1.67,P<0.001); subgroup analysis was conducted according to HIV-1 RNA viral load, CD4⁺ cell count and source of population in the study, results showed that the heterogeneity of this study may be due to veterans group in the study population. Conclusion HIV infection may be one of risks of onset of HF, which may increase onset risk of HF.

Abstract:Objective To investigate the distribution of onychomycosis pathogens and susceptibility of pathogens to commonly used antifungal agents in Hainan Province. Methods Nail scrap specimens of patients with onychomycosis in a hospital from May 2016 to November 2018 were collected, isolated fungal strains were analyzed by culture, identification and in vitro antifungal susceptibility testing. Results A total of 348 patients with onychomycosis were collected, 351 strains of pathogens were isolated. The main pathogens were yeast-like fungi (53.28%), dominantly Candida parapsilosis (22.22%) and Candida albicans (11.40%), followed by Dermatophytes (29.63%), dominantly Trichophyton rubrum (25.07%). Fungal strains were mainly isolated from patients in age groups of 21-30 years old (86 strains), 31-40 years old (77 strains) and 41-50 years old (49 strains); the ratio of male to female patients was 1:1.52. The main clinical types of onychomycosis were distal lateral subungual onychomycosis (47.41%), superficial white onychomycosis(18.97%), and total dystrophic onychomycosis(15.80%). Geometric mean of MIC of Trichophyton rubrum and Trichophyton interdigitale to terbinafine was the lowest, geometric mean of MIC of Fusarium solani to vriconazole was the lowest, geometric mean of MIC of Candida (Candida albicans, Candida parapsilosis, Candida tropicalis, and Candida dubliniensis) to ketoconazole, itraconazole, and vriconazole were all low. Conclusion The main pathogen of onychomycosis in Hainan Province from 2016 to 2018 are yeast-like fungi, ketoconazole, itraconazole and voriconazole are preferred for treatment of onychomycosis.

Abstract:Objective To compare the distribution and antimicrobial resistance of pathogens in non-ventilator hospital-acquired pneumonia (NV-HAP), ventilator-associated pneumonia (VAP) and community-acquired pneumonia (CAP). Methods Medical records of patients with pneumonia in a hospital from October 2017 to September 2019 were retrospectively investigated, according to the definition of NV-HAP, VAP and CAP, patients were divided into NV-HAP group, VAP group and CAP group. Sputum, bronchoalveolar lavage fluid and blood specimens were collected from three groups, difference in constituent and antimicrobial resistance of pathogens of three groups were analyzed. Results A total of 4 391 patients with pneumonia were included, including 1 080 cases in NV-HAP group, 126 in VAP group and 3 185 in CAP group, 841, 191 and 1 440 strains of pathogens were isolated from each group, mostly were Gram-negative bacteria, accounted for 72.77%, 84.82% and 61.18% respectively, difference in distribution of pathogens isolated from three groups was statistically significant (χ²=64.037, P<0.001). Antimicrobial resistance rates of Acinetobacter baumannii to cefepime, cefoperazone/sulbactam, imipenem, gentamicin, tobramycin, levofloxacin, ciprofloxacin and compound sulfamethoxazole, resistance rates of Pseudomonas aeruginosa to cefoperazone/sulbactam and imipenem, as well as resistance rates of Klebsiella pneumoniae to commonly used antimicrobial agents among three groups were all statistically significant (all P<0.05); resistance rates of Staphylococcus aureus to erythromycin, clindamycin and ciprofloxacin in CAP group were all higher than in NV-HAP group (P<0.05). Conclusion NV-HAP, VAP and CAP are different in pathogenic distribution and antimicrobial resis-tance, in the formulation of clinical treatment program, different types of pneumonia should be treated differently.

Abstract:Objective To investigate the characteristics and risk factors of healthcare-associated infection(HAI) after open heart surgery, so as to provide theoretical basis for formulating intervention measures. Methods HAI in patients after open heart surgery in a tertiary heart hospital from January 1, 2016 to June 30, 2019 was investigated retrospectively, risk factors were analyzed. Results A total of 13 236 patients were investigated, 923 had post-opera-tive HAI, HAI rate was 6.97%. HAI rate varied with different surgical procedures, from high to low were complex cardiac surgery (13.32%), macrovascular surgery (11.60%), coronary artery transplantation (8.23%), valve surgery (5.49%), and simple cardiac surgery (5.45%). The main infection was lower respiratory tract infection (n=778, including 154 cases of ventilator-associated pneumonia), followed by upper respiratory tract infection (n=42), bloodstream infection (n=34), surgical site infection (n=27) and urinary tract infection (n=26). Multivariate logistic regression analysis showed that secondary surgery, allogeneic blood transfusion, duration of operation>265 minutes, and complex cardiac surgery were independent risk factors for HAI after open heart surgery. Conclusion Shortening operation time, reducing allogeneic blood transfusion and avoiding secondary surgery are beneficial to the prevention of HAI after open heart surgery.

Abstract:Compressed air is widely used in medical institutions and is known as life support system. However, the quality of compressed air, especially the microbial content, has not been attracted extensive attention. In this paper, preparation, current domestic and foreign implementation standards and existing problems, purification measures, as well as literatures relevant to microbial monitoring technology of compressed air were summarized, aiming at clarifying the contamination sources, control strategies and monitoring methods of compressed air, so as to provide reference for performing future monitoring research as well as formulating standards and specifications.