一起耐碳青霉烯鲍曼不动杆菌感染暴发事件的调查

An outbreak of carbapenem-resistant Acinetobacter baumannii infection

目的调查某院发生的一起疑似耐碳青霉烯鲍曼不动杆菌(CRAB)感染暴发事件,并评价干预措施的效果。方法对2022年2月9—14日该院急诊重症监护病房(EICU)院感监测软件预警的6例检出CRAB患者进行流行病学调查,对可能污染的环境样本进行微生物采样、培养、鉴定及药敏检测,同时采取综合控制措施,并持续监测干预后患者及环境CRAB检出情况。结果6例检出CRAB的患者,其中医院感染4例,定植2例。病例1、3、4、5来源CRAB,除对替加环素和左氧氟沙星中介外,其他全耐药,耐药谱一致。环境卫生学监测显示,暴发时CRAB检出率为20.00%(40/200),分别从床单元、设备仪器、医务人员及保洁员手中检出CRAB,且药敏结果与患者来源菌株一致。采用提高接触隔离落实率,严格执行手卫生,采取全院多科室联合的感染防控培训及督导等针对性干预措施,持续3个月对该科室进行CRAB目标监测,结果发现3—5月CRAB感染率分别为25.00%(12/48)、18.75%(9/48)、12.50%(6/48),呈下降趋势(χ_(趋势)^(2)=56.00,P<0.05);连续环境卫生学采样,均未分离出CRAB,此事件得到有效控制。结论接触隔离落实不足、抗菌药物使用不规范、手卫生执行不到位,以及环境清洁不彻底可能是导致此次CRAB感染暴发的主要原因,及时识别,调查原因,采取针对性的防控策略是有效控制多重耐药菌感染的关键措施。

Objective To investigate an outbreak of suspected carbapenem-resistant Acinetobacter baumannii(CRAB)infection in the emergency intensive care unit(EICU)of a hospital,and evaluate the effect of intervention measures.Methods Epidemiological investigation was carried out on 6 CRAB patients with detection of CRAB and were warned by healthcare-associated infection(HAI)monitoring software in EICU of a hospital from February 9 to 14,2022,environmental specimens that may be contaminated were performed microbial sampling,culture,identification and antimicrobial susceptibility testing,and comprehensive control measures were taken,detection of CRAB in patients and environment after intervention was continuously monitored.Results Among 6 patients with CRAB,4 had HAI and 2 had colonization.Cases 1,3,4 and 5 originated from CRAB,except intermediately resistant to tegacyclin and levofloxacin,they were all resistant other antimicrobial agents and had the same resistance spectrum.Environmental hygiene monitoring showed that the detection rate of CRAB was 20.00%(40/200)in the outbreak,CRAB was detected from bed units,equipment and instruments,health care workers and cleaners,antimicrobial susceptibility results were consistent with the strains from patients.By improving the implementation rate of contact isolation,strictly implementing hand hygiene,taking targeted intervention measures such as joint prevention and control training on infection and supervision of multiple departments in the hospital,CRAB target monitoring was carried out in this department for three months,results showed that CRAB infection rate from March to May were 25.00%(12/48),18.75%(9/48)and 12.50%(6/48)respectively,showing a downward trend(χ_(trend)^(2)=56.00,P<0.05);continuous environmental hygiene sampling didn’t isolate CRAB,and this event was effectively controlled.Conclusion Inadequate implementation of contact isolation,nonstandard use of antimicrobial agents,inadequate implementation of hand hygiene and incomplete environmental cleaning may be the main causes for the outbreak of CRAB,timely identification,investigation and targeted prevention and control strategies are the key mea-sures to effectively control the infection of multidrug-resistant organism.