宏基因组二代测序在耐碳青霉烯类鲍曼不动杆菌医院感染暴发中的应用

目的 探讨宏基因组二代测序(mNGS)技术在耐碳青霉烯类鲍曼不动杆菌(CRAB)医院感染暴发事件调查中的应用。方法 应用mNGS及传统病原学培养方法对某院重症监护病房(ICU)2023年6月8—22日5例检出CRAB患者进行病原学检测，对可能污染的环境进行微生物采样及细菌培养、鉴定和药物敏感试验，同时采取综合控制措施并评价其效果。结果 mNGS结果回报所需时间短于培养所需时间(3.92±1.05)d VS (6.24±0.25)d,P<0.001]。5例患者的标本培养分离出CRAB,mNGS检测结果显示均检出OXA-23耐药基因，经专家综合判断4例患者为医院感染，1例患者为标本污染。依据《医院感染暴发控制指南》中的医院感染暴发定义，此事件考虑为医院感染暴发。环境卫生学监测结果显示，暴发时环境中CRAB检出率为51.30%(59/115),主要集中在医务人员手与呼吸机表面，实施多学科联合感染控制措施后，医生手卫生依从率及呼吸机消毒落实率分别由40.83%(49/120)、33.33%(16/48)提高至82.61%(95/115)、83.33%(30/36)。患者预后良好，后续监...

Application of metagenomic next-generation sequencing in the outbreak of healthcare-associated infection with carbapenem-resistant Acinetobacter baumannii

Objective To explore the application of metagenomic next-generation sequencing (mNGS) technology in the investigation of healthcare-associated infection (HAI) outbreaks of carbapenem-resistant Acinetobacter baumannii (CRAB). Methods Pathogenic detection by mNGS and conventional pathogen culture were performed on 5 patients in the intensive care unit (ICU) of a hospital from June 8 to 22, 2023 from whom CRAB were detected. Microbial sampling was carried out in potentially contaminated environment. Bacterial culture, identification, and antimicrobial susceptibility testing were conducted. Comprehensive control measures were taken, and the effect was evaluated. Results The time required for reporting results by mNGS was shorter than the culture time (3.92 ± 1.05] days vs6.24 ± 0.25] days, P<0.001). CRAB was isolated from the specimens of 5 patients. mNGS detected OXA-23 resistance genes from all patients. After comprehensive assessment by experts, 4 patients were HAI and 1 patient was due to specimen contamination. According to the definition from Guidelines for HAI outbreak control, this event was considered an outbreak of HAI. The monitoring results of environmental hygiene showed that the detection rate of CRAB in the environment during the outbreak was 51.30% (59/115), mainly from the hands of health care workers and the surface of ventilators. After implementing multidisciplinary infection control measures, clinicians'' hand hygiene compliance rate and implementation rate of ventilator disinfection increased from 40.83% (49/120) and 33.33% (16/48) to 82.61% (95/115) and 83.33% (30/36), respectively. The prognosis of patients was good, and no new case emerged during subsequent monitoring. The outbreak of HAI in this hospital has been effectively controlled. Conclusion mNGS is characterized by high precision, less time consumption, and high accuracy, and can be applied to the prevention and control of HAI outbreak and the study of antimicrobial-resistant genomes. It is of great significance for the anti-infection treatment of patients with multidrug-resistant orga-nism infection as well as the formulation of HAI prevention and control measures. Continuous improving disinfection effectiveness and hand hygiene compliance is important for preventing and controlling CRAB infection.