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Since 2011, invasive infections due to Mycobacterium chimaera have been diagnosed in patients with previous cardiac surgery. The use of heating/cooling devices (heater-cooler units), necessary to regulate the blood temperature in extra-corporeal circulation, has been identified as a source of contaminated aerosol. Adhering to a strict maintenance program according to the manufacturer's instructions for use including sanitizing is essential to reduce the risk. Current manufacturer guidelines and national recommendations for detection and decontamination of Mycobacterium chimaera and other non-tuberculosis mycobacteria should organically update units' policies and protocols as they are published.
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Ponte Cardiopulmonar/efeitos adversos , Contaminação de Equipamentos/estatística & dados numéricos , Mycobacterium/patogenicidade , Guias como Assunto , HumanosRESUMO
The role of microplastics (MPs) in the spread of antibiotic resistance genes (ARGs) is increasingly attracting global research attention due to their unique ecological and environmental effects. The ubiquitous use of plastics and their release into the environment by anthropic/industrial activities are the main sources for MP contamination, especially of water bodies. Because of their physical and chemical characteristics, MPs represent an ideal substrate for microbial colonization and formation of biofilm, where horizontal gene transfer is facilitated. In addition, the widespread and often injudicious use of antibiotics in various human activities leads to their release into the environment, mainly through wastewater. For these reasons, wastewater treatment plants, in particular hospital plants, are considered hotspots for the selection of ARGs and their diffusion in the environment. As a result, the interaction of MPs with drug-resistant bacteria and ARGs make them vectors for the transport and spread of ARGs and harmful microorganisms. Microplastic-associated antimicrobial resistance is an emerging threat to the environment and consequently for human health. More studies are required to better understand the interaction of these pollutants with the environment as well as to identify effective management systems to reduce the related risk.
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Microplásticos , Águas Residuárias , Humanos , Plásticos , Genes Bacterianos , Resistência Microbiana a Medicamentos/genética , Antibacterianos/farmacologia , HospitaisRESUMO
Improving the cleaning and disinfection of high-touch surfaces is one of the core components of reducing healthcare-associated infections. The effectiveness of an enhanced protocol applying UV-C irradiation for terminal room disinfection between two successive patients was evaluated. Twenty high-touch surfaces in different critical areas were sampled according to ISO 14698-1, both immediately pre- and post-cleaning and disinfection standard operating protocol (SOP) and after UV-C disinfection (160 sampling sites in each condition, 480 in total). Dosimeters were applied at the sites to assess the dose emitted. A total of 64.3% (103/160) of the sampling sites tested after SOP were positive, whereas only 17.5% (28/160) were positive after UV-C. According to the national hygienic standards for health-care setting, 9.3% (15/160) resulted in being non-compliant after SOP and only 1.2% (2/160) were non-compliant after UV-C disinfection. Operation theaters was the setting that resulted in being less compliant with the standard limit (≤15 colony-forming unit/24 cm2) after SOP (12%, 14/120 sampling sites) and where the UV-C treatment showed the highest effectiveness (1.6%, 2/120). The addition of UV-C disinfection to the standard cleaning and disinfection procedure had effective results in reducing hygiene failures.
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Infecção Hospitalar , Robótica , Humanos , Desinfecção/métodos , Xenônio , Hospitais , Raios UltravioletaRESUMO
Background: Correct reprocessing and microbiological surveillance on endoscopes are fundamental for preventing the transmission of multi-drug resistant strains and device-related infections. Methods: A questionnaire with three domains was created: (1) centre characteristics; (2) endoscope reprocessing procedures; and (3) application of microbiological surveillance. Nurses working in endoscopic units across Italy were invited to anonymously fill out the questionnaire on the SurveyMonkey platform between November 2021 and February 2022. Results: A total of 82 out of 132 endoscopic centres participated in the survey, with at least one centre from each Italian region. Data found different concerns regarding the current practice of both reprocessing and microbiological surveillance. According to respondents, the training on reprocessing was performed through theoretical training and only in 10% of centres; the microbiological surveillance was regularly performed in 59% of centres; and sampled endoscopes were not excluded for use in 31% of centres performing the surveillance until the outcome was pending, and when positive, 72% maintained them in quarantine until a successive negative result. Conclusions: Reprocessing and microbiological surveillance currently present several criticisms along the endoscopic centres in Italy. Our survey highlights the need for the correct application of the national recommendations in each endoscopic centre to prevent the potential transmission of endoscope-related infections.
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Desinfecção , Contaminação de Equipamentos , Desinfecção/métodos , Endoscópios , Contaminação de Equipamentos/prevenção & controle , Humanos , Itália , Inquéritos e QuestionáriosRESUMO
Background: Vaccination of healthcare workers (HCWs) is a crucial element to overcome the COVID-19 pandemic. The aim of this survey was to assess attitudes, sources of information and practices among Italian Healthcare workers (HCWs) in relation to COVID-19 vaccination. Methods: From 19 February to 23 April 2021, an anonymous voluntary questionnaire was sent to the mailing list of the main National Health Service structures. Data were collected through the SurveyMonkey platform. Results: A total of 2137 HCWs answered. Hesitancy towards COVID-19 vaccination was more frequent in females, in those with lower concern about COVID-19, and in nurses, auxiliary nurses (AN) and healthcare assistants. Hesitant professionals were more likely to not recommend vaccination to their patients or relatives, while a high concern about COVID-19 was related to an increased rate of recommendation to family members. HCWs were mostly in favor of mandatory vaccination (61.22%). Female sex, a lower education level, greater hesitancy and refusal to adhere to flu vaccination campaigns were predictors influencing the aversion to mandatory vaccination. All categories of HCWs referred mainly to institutional sources of information, while scientific literature was more used by professionals working in the northern regions of Italy and in infection control, infectious diseases, emergencies and critical areas. HCWs working in south-central regions, nurses, AN, healthcare technicians, administrators and HCWs with a lower education level were more likely to rely on internet, television, newspapers, and the opinions of family and friends. Conclusions: Communication in support of COVID-19 immunization campaigns should consider the differences between the various HCWs professional categories in order to efficiently reach all professionals, including the most hesitant ones.
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Vacinas contra COVID-19 , COVID-19 , Atitude , Estudos Transversais , Feminino , Pessoal de Saúde , Humanos , Pandemias , SARS-CoV-2 , Medicina Estatal , VacinaçãoRESUMO
In dental clinics, the infections may be acquired through contaminated devices, air, and water. Aerosolized water may contain bacteria, grown into the biofilm of dental unit waterlines (DUWLs). We evaluated a disinfection method based on water osmosis and chlorination with chlorine dioxide (O-CD), applied to DUWL of five dental clinics. Municipal water was chlorinated with O-CD device before feeding all DUWLs. Samplings were performed on water/air samples in order to research total microbial counts at 22-37 °C, Pseudomonas aeruginosa, Legionella spp., and chlorine values. Water was collected from the taps, spittoons, and air/water syringes. Air was sampled before, during, and after 15 min of aerosolizing procedure. Legionella and P. aeruginosa resulted as absent in all water samples, which presented total microbial counts almost always at 0 CFU/mL. Mean values of total chlorine ranged from 0.18-0.23 mg/L. Air samples resulted as free from Legionella spp. and Pseudomonas aeruginosa. Total microbial counts decreased from the pre-aerosolizing (mean 2.1 × 102 CFU/m3) to the post-aerosolizing samples (mean 1.5 × 10 CFU/m3), while chlorine values increased from 0 to 0.06 mg/L. O-CD resulted as effective against the biofilm formation in DUWLs. The presence of residual activity of chlorine dioxide also allowed the bacteria reduction from air, at least at one meter from the aerosolizing source.
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Desinfecção , Legionella , Bactérias , Biofilmes , Cloro/farmacologia , Compostos Clorados , Contagem de Colônia Microbiana , Equipamentos Odontológicos , Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Osmose , Óxidos , Pseudomonas aeruginosa , Água , Microbiologia da ÁguaRESUMO
BACKGROUND: In the past few decades, the inadequate reprocessing of bronchoscopes has been associated with several serious outbreaks caused by multidrug-resistant microorganisms. In this study we evaluated the improvement in the quality of reprocessing in a Bronchoscopy Unit (BU), after the introduction of a new procedure. METHODS: In 2019, observational and clinical audits were conducted in the BU. After the introduction of an improved procedure in 2020, a microbiological surveillance plan was implemented in 2021. RESULTS: In 2019, 13 of 22 bronchoscopes (59%) resulted as non-compliant, 18% as high concern organisms (HCO) and 36.4% as high microbial count (≥100 CFU/all channels) and HCO. The most frequent microorganisms were Staphylococcus aureus (38.5%) and NDM-producing Klebsiella pneumoniae (15.4%). The bronchoscopes were stored inside their transport cases, which in some cases were found to be contaminated by the same strains isolated on the bronchoscopes (Enterobacter gergoviae and Vibrio alginolyticus). In 2021, all 31 bronchoscopes were sampled at least three times and 13/99 (13.1%) resulted as non-compliant, mostly K. pneumoniae (4.04%). Contamination level increases weakly in bronchoscopes in use for more than 14 years (R = 0.32). CONCLUSIONS: The adoption of an improved reprocessing procedure decreased the non-compliance of bronchoscopes, increasing the quality of the process and patient safety.
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Broncoscópios , Infecção Hospitalar , Broncoscópios/microbiologia , Infecção Hospitalar/epidemiologia , Desinfecção/métodos , Contaminação de Equipamentos/prevenção & controle , Klebsiella pneumoniaeRESUMO
A viral spread occurrence such as the SARS-CoV-2 pandemic has prompted the evaluation of different disinfectants suitable for a wide range of environmental matrices. Chlorine dioxide (ClO2) represents one of the most-used virucidal agents in different settings effective against both enveloped and nonenveloped viruses. This narrative synthesis is focused on the effectiveness of ClO2 applied in healthcare and community settings in order to eliminate respiratory transmitted, enteric, and bloodborne viruses. Influenza viruses were reduced by 99.9% by 0.5-1.0 mg/L of ClO2 in less than 5 min. Higher concentration (20 mg/L) eliminated SARS-CoV-2 from sewage. ClO2 concentrations from 0.2 to 1.0 mg/L ensured at least a 99% viral reduction of AD40, HAV, Coxsackie B5 virus, and other enteric viruses in less than 30 min. Considering bloodborne viruses, 30 mg/L of ClO2 can eliminate them in 5 min. Bloodborne viruses (HIV-1, HCV, and HBV) may be completely eliminated from medical devices and human fluids after a treatment with 30 mg/L of ClO2 for 30 min. In conclusion, ClO2 is a versatile virucidal agent suitable for different environmental matrices.
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The European dependencies for raw materials supply from foreign countries have been unquestionably shown by COVID-19 outbreak and have become particular evident from the slow response to the need for high quality personal protective equipment (PPEs). Among all medical devices, surgical face masks have earned themselves a primary role for the containment of the epidemic. In this context, our work aims at improving the barrier effect of surgical mask by depositing on their external surface a mixture of bioactive compounds, mainly polyphenols, extracted from agronomical sources. The main objective is the integration of the biorefining of agri-food solid wastes with the potential virucidal properties of the polyphenolic extracts for the treatment of PPEs.
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Background: Failure in the reprocessing of thermolabile flexible endoscopes has been reported as one of the most important threats to patient health. Method: A case report and observational study was conducted, from August 2014 to December 2019, in the Digestive Endoscopy Unit of a University Hospital in Italy, where two cases of Klebsiella pneumoniae carbapenemase (KPC)-producing Klebsiella pneumoniae infections in patients undergoing endoscopic retrograde cholangio-pancreatography were observed. Following the risk/safety management practices, an epidemiological investigation was started, duodenoscopes were removed from use and the reprocessing practices reviewed. Moreover, microbiological surveillance of endoscopes was carried out according to the CDC guidelines. Results: In the first phase of sampling, 10/10 (100%) endoscopes were found to be non-compliant, of which 7 showed results for high-concern organisms (HCOs), such as KPC-K. pneumoniae, P. aeruginosa and E. coli. After implementing corrective actions, 12 out of 17 endoscopes were found to be non-compliant (70.5%), of which 8 showed results for HCOs, such as KPC-K. oxytoca and P. aeruginosa. During the last year of regular microbiological surveillance, only 23% of endoscopes (35/152) were found to be non-compliant, of which 7 showed results for HCOs, such as NDM-K. pneumoniae, P. aeruginosa and A. baumannii. The crucial issues were related to samples collected from the internal channels of duodenoscopes. Conclusion: Managing the risk associated with the reprocessing of digestive endoscopes, through risk assessment at every stage of the process, is important for the prevention of infections associated with the use of these device.
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Contaminação de Equipamentos , Escherichia coli , Desinfecção , Duodenoscópios , Endoscópios , Contaminação de Equipamentos/prevenção & controle , Humanos , ItáliaRESUMO
The emergence of multiresistant bacterial strains as agents of healthcare-related infection in hospitals has prompted a review of the control techniques, with an added emphasis on preventive measures, namely good clinical practices, antimicrobial stewardship, and appropriate environmental cleaning. The latter item is about the choice of an appropriate disinfectant as a critical role due to the difficulties often encountered in obtaining a complete eradication of environmental contaminations and reservoirs of pathogens. The present review is focused on the effectiveness of hydrogen peroxide vapor, among the new environmental disinfectants that have been adopted. The method is based on a critical review of the available literature on this topic.
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Introduction: Dental Unit Waterlines (DUWLs) have shown to be a source of Legionella infection. We report the experience of different dental healthcare settings where a risk management plan was implemented. Materials and methods: In a Hospital Odontostomatology Clinic (HOC) and three Private Dental Clinics (PDCs) housing 13 and six dental units (DUs), respectively, an assessment checklist was applied to evaluate staff compliance with guideline recommendations. DUWLs microbial parameters were investigated before and after the application of corrective actions. Results: In the HOC a poor adherence to good practices was demonstrated, whereas protocols were carefully applied in PDCs. L. pneumophila sg 2-15 was isolated in 31% (4/13) and 33% (2/6) of DUs in HOC and PDCs, respectively, mainly from handpieces (32%, 6/19) with counts >102 colony-forming units per milliliter (CFU/L), often associated with P. aeruginosa (68%, 13/19). The shock disinfection with 3% v/v hydrogen peroxide (HP) showed a limited effect, with a recolonization period of about 4 weeks. Legionella was eradicated only after 6% v/v HP shock disinfection and filters-installation, whilst P. aeruginosa after the third shock disinfection with a solution of 4% v/v HP and biodegradable surfactants. Conclusions: Our data demonstrate the presence and persistence of microbial contamination within the DUWLs, which required strict adherence to control measures and the choice of effective disinfectants.
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The bio-engineering technologies of medical devices through nano-structuring and coating was recently proposed to improve biocompatibility and to reduce microbial adhesion in the prevention of implantable device-related infections. Our aim was to evaluate the ability of new nano-structured and coated materials to prevent the adhesion and biofilm formation, according to the American Standard Test Method ASTM-E2647-13. The materials composition was determined by X-ray Fluorescence and Laser Induced Breakdown Spectroscopy. Silver release was evaluated by Inductively Coupled Plasma Mass Spectrometry analysis. The gene expression levels of the Quorum Sensing Las and Rhl system were evaluated by the ΔΔCt method. The Log bacterial density (Log CFU/cm2) on TiAl6V4 was 4.41 ± 0.76 and 4.63 ± 1.01 on TiAl6V4-AgNPs compared to 2.57 ± 0.70 on CoCr and 2.73 ± 0.61 on CoCr-AgNPs (P < 0.0001, A.N.O.V.A.- one way test). The silver release was found to be equal to 17.8 ± 0.2 µg/L after the batch phase and 1.3 ± 0.1 µg/L during continuous flow. The rhlR gene resulted in a 2.70-fold increased expression in biofilm growth on the silver nanoparticles (AgNPs) coating. In conclusion, CoCr showed a greater ability to reduce microbial adhesion, independently of the AgNPs coating. The silver release resulted in promoting the up-regulation of the Rhl system. Further investigation should be conducted to optimize the effectiveness of the coating.
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Resinas Acrílicas/farmacologia , Antibacterianos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Prótese Articular/microbiologia , Nanopartículas Metálicas/administração & dosagem , Prata/farmacologia , Resinas Acrílicas/administração & dosagem , Prata/administração & dosagemRESUMO
Microbiological surveillance carried out in order to verify the effectiveness of endoscope reprocessing does not include the research of viruses, although endoscopes may be associated with the transmission of viral infections. This paper reports the experience of the University Hospital of Pisa in managing the risk from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during an endoscopy. A review of the reprocessing procedure was conducted to assess whether improvement actions were needed. To verify the reprocessing efficacy, a virological analysis was conducted both before and after the procedure. Five bronchoscopes and 11 digestive endoscopes (6 gastroscopes and 5 colonoscopes) were sampled. The liquid samples were subjected to concentration through the use of the Macrosep Advance Centrifugal Devices (PALL Life Sciences, Port Washington, NY, USA) and subsequently analyzed using the cobas® SARS-CoV-2 Test (Roche Diagnostics, Basel, Switzerland), together with eSwab 490 CE COPAN swabs (COPAN, Brescia, Italy), which were used to sample surfaces. In accordance with the first ordinance regarding the coronavirus disease 2019 (COVID-19) emergency issued by the Tuscany Region in March 2020, a procedure dedicated to the management of the COVID-19 emergency in endoscopic practices was prepared, including the reprocessing of endoscopes. The virological analysis carried out on samples collected from endoscopes after reprocessing gave negative results, as well as on samples collected on the endoscopy column surfaces and the two washer-disinfectors that were dedicated to COVID-19 patients. The improvement in endoscope reprocessing implemented during the COVID-19 emergency was effective in ensuring the absence of SARS-CoV-2, thus reducing the risk of infections after an endoscopy on COVID-19 patients.
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Infecções por Coronavirus/prevenção & controle , Desinfecção/normas , Endoscopia/instrumentação , Contaminação de Equipamentos/prevenção & controle , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Betacoronavirus , COVID-19 , Humanos , Itália , SARS-CoV-2RESUMO
Implementation of environmental cleaning and disinfection has been shown to reduce the incidences of healthcare-associated infections. The effect of an enhanced strategy for terminal room disinfection, applying the pulsed xenon-based ultraviolet light no-touch disinfection systems (PX-UVC) after the current standard operating protocol (SOP) was evaluated. In a teaching hospital, the effectiveness in reducing the total bacterial count (TBC) and in eliminating high-concern microorganisms was assessed on five high-touch surfaces in different critical areas, immediately pre- and post-cleaning and disinfection procedures (345 sampling sites). PX-UVC showed only 18% (15/85) of positive samples after treatment compared to 63% (72/115) after SOP. The effectiveness of PX-UVC was also observed in the absence of manual cleaning and application of a chemical disinfectant. According to the hygienic standards proposed by the Italian Workers Compensation Authority, 9 of 80 (11%) surfaces in operating rooms showed TBC ≥15 CFU/24 cm2 after the SOP, while all samples were compliant applying the SOP plus PX-UVC disinfection. Clostridium difficile (CD) spores and Klebsiella pneumoniae (KPC) were isolated only after the SOP. The implementation of the standard cleaning and disinfection procedure with the integration of the PX-UVC treatment had effective results in both the reduction of hygiene failures and in control environmental contamination by high-concern microorganisms.
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Desinfecção/métodos , Raios Ultravioleta , Xenônio , Carga Bacteriana , Clostridioides difficile/isolamento & purificação , Infecção Hospitalar/prevenção & controle , Hospitais de Ensino , Humanos , Itália , Klebsiella pneumoniae/isolamento & purificação , Salas CirúrgicasRESUMO
Studies conducted over the last 40 years have demonstrated that the water output from dental unit waterlines (DUWLs) is often contaminated with high densities of microorganisms. It has been monitored the microbiological quality of the water in 30 public dental facilities in northern Italy in order to assess the health risk for patients and dental staff. In each facility, samples of water both from taps and from DUWLs were analyzed in order to evaluate heterotrophic plate counts (HPCs) at 22 °C and 36 °C, and to detect coliform bacteria, Pseudomonas aeruginosa, Legionella pneumophila and amoebae. In 100% of the samples taken from the DUWLs, the concentration of HPCs was above the threshold as determined by the Ministère de la Santé et des Solidarités (2007). The concentration of P. aeruginosa was greater than the indicated threshold in 16.67% of the hand-pieces analyzed. A total of 78.33% of samples were contaminated by L. pneumophila, while in the samples taken from the DUWLs alone, this percentage rose to 86.67%. Amoebae were detected in 60% of the samples taken from hand-pieces; all belonging to the species V. vermiformis. This study documented the presence of various microorganisms, including Legionella spp., at considerably higher concentrations in water samples from DUWLs than in samples of tap water in the same facilities, confirming the role of the internal DUWLs in increasing microbial contamination, especially in the absence of proper management of waterborne health risks.
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Equipamentos Odontológicos/microbiologia , Contaminação de Equipamentos , Microbiologia da Água , Amoeba , Enterobacteriaceae , Monitoramento Ambiental , Itália , Legionella pneumophila , Pseudomonas aeruginosaRESUMO
In healthcare facilities, environmental surfaces may be a reservoir of infectious agents even though cleaning and disinfection practices play a role in the control of healthcare-associated infections. In this study, the effectiveness of cleaning/disinfection procedures has been evaluated in two hospital areas, which have different risk category classifications. According to the contract with the cleaning service, after the daily ambulatory activities, the housekeeping staff apply an alcohol-based detergent followed by a chlorine-based disinfectant (2% Antisapril, Angelini; 540 mg/L active chlorine), properly diluted and sprayed. The contract provides for the use of disposable microfiber wipes which must be replaced with new ones in each health out-patient department. Surface contamination was analyzed using cultural methods and ATP detection, performed with a high-sensitivity luminometer. The values 100 CFU/cm² and 40 RLU/cm² were considered as the threshold values for medium-risk category areas, while 250 CFU/cm² and 50 RLU/cm² were defined for the low-risk category ones. Air quality was evaluated using active and passive sampling microbiological methods and particle count (0.3 µmâ»10 µm) detection. The cleaning/disinfection procedure reduced the medium bacterial counts from 32 ± 56 CFU/cm² to 2 ± 3 CFU/cm² in the low-risk area and from 25 ± 40 CFU/cm² to 7 ± 11 CFU/cm² in the medium-risk one. Sample numbers exceeding the threshold values decreased from 3% and 13% to 1% and 5%, respectively. RLU values also showed a reduction in the samples above the thresholds from 76% to 13% in the low-risk area. From the air samples collected using the active method, we observed a reduction of 60% in wound care and 53% in an ambulatory care visit. From the air samples collected using the passive method, we highlighted a 71.4% and 50% reduction in microbial contamination in the medium-risk area and in the low-risk one, respectively. The 10 µm size particle counts decreased by 52.7% in wound care and by 63% in the ambulatory care visit. Correct surface sanitation proved crucial for the reduction of microbial contamination in healthcare settings, and plays an important role in ensuring air quality in hospital settings.
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OBJECTIVES: To evaluate the effectiveness of hydrogen peroxide (HP) use as a disinfectant in the hospital water network for the control of Legionella spp. colonization. METHODS: Following the detection of high levels of Legionella contamination in a 136-bed general hospital water network, an HP treatment of the hot water supply (25 mg/L) was adopted. During a period of 34 months, the effectiveness of HP on Legionella colonization was assessed. Legionella was isolated in accordance with ISO-11731 and identification was carried out by sequencing of the mip gene. RESULTS: Before HP treatment, L. pneumophila sg 2-15 was isolated in all sites with a mean count of 9950 ± 8279 cfu/L. After one-month of HP treatment, we observed the disappearance of L. pneumophila 2-15, however other Legionella species previously not seen were found; Legionellapneumophila 1 was isolated in one out of four sampling sites (2000 cfu/L) and other non-pneumophila species were present in all sites (mean load 3000 ± 2887 cfu/L). Starting from September 2013, HP treatment was modified by adding food-grade polyphosphates, and in the following months, we observed a progressive reduction of the mean load of all species (p < 0.05), resulting in substantial disappearance of Legionella colonization. CONCLUSION: Hydrogen peroxide demonstrated good efficacy in controlling Legionella. Although in the initial phases of treatment it appeared unable to eliminate all Legionella species, by maintaining HP levels at 25 mg/L and adding food-grade polyphosphates, a progressive and complete control of colonization was obtained.