Verdial C, Carneiro C, Machado I, Tavares L, Almeida V, Oliveira M, Gil S
Faculty of Veterinary Medicine, University of Lisbon, Av. Universidade Técnica, 1300-477, Lisbon, Portugal.
CIISA - Centre for Interdisciplinary Research in Animal Health, Faculty of Veterinary Medicine, University of Lisbon, Av. Universidade Técnica, 1300-477, Lisbon, Portugal.
Ir Vet J. 2021 Jun 28;74(1):18. doi: 10.1186/s13620-021-00197-z.
The Biological Isolation and Containment Unit (BICU) is a subunit of the Teaching Hospital of the Faculty of Veterinary Medicine of the University of Lisbon, Portugal, for the admission of animals with confirmed infectious diseases or under clinical suspicion and waiting for a diagnosis. As a high-risk environment for the transmission of infectious agents, it is extremely important to implement programs for the surveillance of nosocomial microorganisms in these facilities. The purpose of this study was to evaluate the level of bacterial contamination of the BICU environmental surfaces and to implement corrective actions on disinfection protocols. Swab samples were collected from selected environmental surfaces in 3 different areas of the BICU (isolation, work, and preparatory rooms) to evaluate the total aerobic bacterial load and investigate the presence of 4 nosocomial microorganisms: vancomycin-resistant Enterococcus spp., methicillin-resistant Staphylococcus aureus, 3rd-generation cephalosporin-resistant Escherichia coli, and carbapenem-resistant Pseudomonas aeruginosa. Bacterial quantification was performed by using non-selective media, while specific selective media were used for the isolation of the target microorganisms. Isolates were identified based on their macro and microscopic characteristics and their biochemical profile. Subsequently, new disinfection protocols were implemented, and their effectiveness evaluated.
The surfaces with the highest bacterial load in the isolation, preparatory, and worker's rooms were the cages, hand-held sponge, and telephone, respectively. Regarding the 4 pathogens investigated, Enterococcus spp. were the most frequently isolated (11.3%), followed by E. coli (1.5%) and P. aeruginosa (1.5%). One of the P. aeruginosa isolates obtained was resistant to imipenem. In the end, new disinfection protocols were implemented, which proved to be effective in reducing bacterial counts by 99.99% in cages and the sponge, and by 90 to 99% on the telephone.
This study allows to conclude that the cages and the human contact surfaces were the most contaminated in the isolation rooms. Nevertheless, the new disinfection strategies seemed to be effective in reducing environmental contamination, including by some potentially nosocomial agents, although more samples must be analyzed for definitive conclusions. These results may contribute to highlight the importance of infection prevention and control measures, as fundamental tools to reduce the spread of infectious agents in the hospital environment.
生物隔离与控制单元（BICU）是葡萄牙里斯本大学兽医学院教学医院的一个子单元，用于收治确诊患有传染病或临床疑似且等待诊断的动物。作为传染病原体传播的高风险环境，在这些设施中实施医院微生物监测计划极为重要。本研究的目的是评估BICU环境表面的细菌污染水平，并对消毒方案采取纠正措施。从BICU的3个不同区域（隔离室、工作间和准备室）选定的环境表面采集拭子样本，以评估需氧细菌总数，并调查4种医院感染微生物的存在情况：耐万古霉素肠球菌属、耐甲氧西林金黄色葡萄球菌、耐第三代头孢菌素大肠杆菌和耐碳青霉烯铜绿假单胞菌。使用非选择性培养基进行细菌定量，同时使用特定的选择性培养基分离目标微生物。根据分离株的宏观和微观特征及其生化特性进行鉴定。随后，实施了新的消毒方案，并评估其有效性。
隔离室、准备室和工作间中细菌载量最高的表面分别是笼子、手持海绵和电话。在所调查的4种病原体中，肠球菌属分离频率最高（11.3%），其次是大肠杆菌（1.5%）和铜绿假单胞菌（1.5%）。获得的一株铜绿假单胞菌分离株对亚胺培南耐药。最后，实施了新的消毒方案，结果证明该方案在降低笼子和海绵上的细菌数量方面有效，细菌数量减少了99.99%，在电话上减少了90%至99%。
本研究可以得出结论，隔离室中笼子和与人接触的表面污染最为严重。然而，新的消毒策略似乎在减少环境污染方面有效，包括一些潜在的医院感染病原体，尽管必须分析更多样本才能得出明确结论。这些结果可能有助于凸显感染预防和控制措施的重要性，将其作为减少医院环境中传染病原体传播的基本工具。
