Microplastics and Antibiotic Resistance: The Magnitude of the Problem and the Emerging Role of Hospital Wastewater

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.

Implementation of an Environmental Cleaning Protocol in Hospital Critical Areas Using a UV-C Disinfection Robot

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.

Microbiological surveillance post-reprocessing of flexible endoscopes used in digestive endoscopy: a national study

INTRODUCTION

Microbiological surveillance of endoscopes is a safety measure for verifying the quality of reprocessing procedures and identifying contaminated devices, but duodenoscope-related outbreaks are still reported.

AIM

To assess the effectiveness of duodenoscope reprocessing procedures in Italy.

METHODS

Between December 2019 and April 2020, data obtained from microbiological surveillance post-reprocessing in 15 Italian endoscopy units were collected. Sampling was carried out after reprocessing or during storage in a cabinet. In keeping with international guidelines and the Italian position paper, the micro-organisms were classified as high-concern organisms (HCOs) and low-concern organisms (LCOs).

FINDINGS

In total, 144 samples were collected from 51 duodenoscopes. Of these, 36.81% were contaminated: 22.92% were contaminated with HCOs and 13.89% were contaminated with LCOs [2.08% with an LCO load of 11-100 colony-forming units (CFU)/device and 0.69% with an LCO load of >100 CFU/device]. The contamination rate was 27.5% in samples collected after reprocessing, 40% in samples collected during storage in a cabinet that was compliant with EN 16442:2015 (C-I), and 100% in samples collected during storage in a cabinet that was not compliant with EN 16442:2015 (NC-I). The respective HCO rates were 15.00%, 27.27% and 66.67%. Correlation between LCO contamination and storage time was demonstrated (Spearman's rho=0.3701; P=0.0026). The Olympus duodenoscope TJFQ180V demonstrated the lowest rate of contamination (29.82%), although the contamination rate was 100% for duodenoscopes stored in an NC-I cabinet.

CONCLUSION

Microbiological surveillance, along with strict adherence to reprocessing protocols, may help to detect endoscope contamination at an early stage, and reduce the risk of duodenoscope-associated infections.

Adoption of Improved Reprocessing Decreased Microbiological Non-Compliance for Bronchoscopes

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.

Good Practices on Endoscope Reprocessing in Italy: Findings of a Nationwide Survey

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.

Effectiveness of a Water Disinfection Method Based on Osmosis and Chlorine Dioxide for the Prevention of Microbial Contamination in Dental Practices

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.

Healthcare Workers Attitudes, Practices and Sources of Information for COVID-19 Vaccination: An Italian National Survey

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.

Effectiveness of Disinfection with Chlorine Dioxide on Respiratory Transmitted, Enteric, and Bloodborne Viruses: A Narrative Synthesis

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.

Agri-Food Extracts Effectiveness in Improving Antibacterial and Antiviral Properties of Face Masks: A Proof-of-Concept Study

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.

Improving the Reprocessing Quality of Flexible Thermolabile Endoscopes: How to Learn from Mistakes

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.

Microbiological surveillance in reducing potential infection risk

Background

Failure in reprocessing of endoscopes has been reported as one of the top ten most important threats to patient health.

Materials/Methods

The study was conducted in two digestive endoscopy centres of a teaching hospital (29,000 endoscopies/year, of which 550 endoscopic retrograde cholangiopancreatography (ERCP). Following two cases of bacteremia due to KPC-producing Klebsiella pneumoniae temporally related to ERCP and 89% of non-compliance detected on endoscopes subjected to microbiological surveillance, the reprocessing activities were audited and implemented to ensure guideline compliance. Clinical and microbiological surveillance were reinforced and all responsibilities for each phase identified according to UNI/TR11662. Microbiological surveillance was performed according to the 'Duodenoscope Surveillance Sampling and Culturing Protocols' protocol, CDC, 2018.

Results

In the 11 months of surveillance, 47 endoscopes were sampled (13 colonoscopes, 9 gastroscopes, 23 duodenoscopes and 2 echoendoscopes), 19 washer-disinfector machines and 9 medical cabinets. 36% (17/47) of endoscope internal channels resulted non-compliant, 17% (4/23) in duodenoscopes. NDM-producing K. pneumoniae was isolated in 2 gastroscopes always associated with the use on a colonized patient. The inlet and final rinsing water of washer-disinfectors and medical cabinets resulted always conformed. Non-conformities were managed immediately in order to avoid infectious risks for patients.

Conclusions

Microbiological surveillance of endoscopes after reprocessing allowed to prevent infections in patients undergoing endoscopic procedures.

Key messages

Training of health workers followed by strict adherence to guidelines is the most appropriate tool in preventing and controlling infections related to the use of endoscopes. Endoscopy and reprocessing staff should follow a formal recognized endoscopy reprocessing training program, followed by regular practice and periodically updated training to maintain competency.

Surveillance and control of M. chimaera infections in the Tuscany Region, Italy

Background

Disseminated M. chimaera infections among patients who underwent open-chest surgery with cardiopulmonary bypass have been associated with the contamination of heater-cooler devices (HCDs). The Tuscany region in the Decree 3822/2019 issued recommendations for the surveillance and control of M. chimaera infections.

Methods

In three Tuscan cardiac surgery centers, the case finding was carried out through evaluation and testing of patients with a history of HCD exposure (past 6 years) was performed. Water and aerosol samples were analyzed from each HCDs to determine the microbiological parameters required by the Directive 98/83/CE and to assess the presence of non-tuberculous mycobacteria (NTMs), according to the regional protocol.

Results

M. chimaera infection was not found in any patient and all clinical specimens tested negative. 22 HCDs were sampled (n.12 LivaNova, n.1 Terumo and n.9 Maquet) for a total of 114 samples (45, 8, 2 and 59 respectively). All the microbiological parameters were compliant, excepted for total microbial count at 36 °C that exceeded 100 CFU/ml in 50% (57/114) of samples and for the presence of P.aeruginosa in 10% (12/114). NTMs were detected in 16% (18/114) of HCDs: M. chimaera was identified in 11% (13/114) of samples and in 4% (5/114) M. gordonae. All aerosol samples were negative for NTMs, but in the HCDs Maquet, B.cereus were detected in 7% (4/59) of the samples, K.oxytoca in 2% (1/59), B.ursincola in 2% (1/59) and S. paucimobilis in 3% (2/59). Only S. paucimobilis was isolated also in the same HCD water sample.

Conclusions

The implementation of maintenance and disinfection procedures of HCDs was able to reduce the risk of contamination and aerosolization by NTMs but not of other microorganisms.

Key messages

Further strategies should be put in place for the cases finding. Moreover, reliable decontamination and identification of agents that can disrupt biofilms and increase chlorine susceptibility of mycobacteria are required.

Prevention and Control of Legionella and Pseudomonas spp. Colonization in Dental Units

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.

Evaluation of Microbial Adhesion and Biofilm Formation on Nano-Structured and Nano-Coated Ortho-Prosthetic Materials by a Dynamic Model

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.

Detection and decontamination of Mycobacterium chimaera and other non-tuberculosis mycobacteria in heater-cooler devices used in cardiopulmonary bypass: a Manufacturer and National guidelines summary, and a potential resolution to the problem requiring further investigation

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.

Evaluation of Microbiological and Free-Living Protozoa Contamination in Dental Unit Waterlines

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.

Evaluation of the Cleaning Procedure Efficacy in Prevention of Nosocomial Infections in Healthcare Facilities Using Cultural Method Associated with High Sensitivity Luminometer for ATP Detection

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 μm⁻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.