Monitoraggio degli indicatori di contaminazione fecale di fiumi della fascia costiera Apuo Versiliese per la valutazione della qualita delle acque di balneazione

Negli ultimi anni, particolare attenzione è stata rivolta alla protezione della salute umana dal rischio igienico-sanitario associato alla balneazione. Il litorale apuo-versiliese è una fascia costiera in cui la qualità delle acque di balneazione è compromessa dalla presenza delle foci fluviali di tre piccoli corsi d'acqua, i fossi Fiumetto, Motrone e Abate, che per questo motivo saranno oggetto di una sperimentazione volta all'abbattimento delle cariche microbiche, con impianti di sanificazione che verranno posizionati entro la fine del 2015. Le acque contaminate trasportate dai fiumi possono infatti ripercuotersi sull'idoneità alla balneazione delle acque di mare che ricevono i loro apporti e, nel lungo periodo, sulla classificazione delle aree di balneazione secondo quanto previsto dalla normativa vigente (D. Lgs. 116/08). Per approfondire il contesto microbiologico sono stati analizzati campioni raccolti in prossimità delle foci fluviali. L'analisi è stata estesa, oltre agli indicatori batterici di contaminazione fecale, anche ad adenovirus umano e ai patogeni batterici. Tra gli indicatori batterici sono stati scelti E. coli e enterococchi intestinali ed adenovirus umano. Tra i microrganismi patogeni è stata scelta Salmonella spp. Il prelievo dei campioni è stato effettuato da ponti e i campioni sono stati trasportati in laboratorio Sono stati raccolti volumi diversi in relazione al tipo di analisi: taniche da 10L per adenovirus, bottiglie da 1L per Salmonella spp. e provette da 50 ml per gli indicatori di contaminazione fecale. Gli indicatori di contaminazione fecale sono stati determinati attraverso kit commerciali standardizzati ISO 9308-3 per E. coli e ISO 7899-1 per enterococchi. La presenza di Salmonella spp. è stata determinata attraverso il metodo delle membrane filtranti, seguendo il protocollo ISPRA, sezione 7000 “Metodi per la determinazione di microrganismi indicatori d'inquinamento e di patogeni” (APAT, 2003). Il metodo consente di valutare la presenza/assenza di Salmonella in un determinato volume di acqua (1 litro). I campioni per la ricerca virale sono sottoposti a ultrafiltrazione tangenziale a due stadi per la concentrazione delle particelle virali e successivo trattamento al cloroformio per l'abbattimento della carica batterica e la rimozione dei contaminanti chimici. I concentrati sono analizzati attraverso metodo molecolare ,PCR quantitativa. L'indagine molecolare consiste in una fase preliminare di estrazione del genoma virale seguita da Real Time PCR. Il monitoraggio condotto sui tre corsi d'acqua ha mostrato complessivamente una ridotta concentrazione dei batteri indicatori. Sono state rilevate positività per E. coli in 11 e per enterococchi in 14 dei 26 campioni esaminati, mentre per gli altri campioni i livelli dei batteri indicatori sono risultati inferiori rispetto al limite di rilevabilità della tecnica di 0.38 MPN/100ml. Nelle due date in cui il prelievo è stato effettuato con pioggia (27 Luglio e 24 Agosto), tutti i campioni sono risultati positivi agli indicatori, ed inoltre in queste date sono stati registrati i livelli di batteri indicatori più elevati: 3.5 MPN/100 ml per gli enterococchi nel fosso Motrone nel prelievo del 27 Luglio e 93.66 MPN/100ml per E. coli nel fosso Fiumetto nel prelievo del 24 Agosto. Tutti i campioni analizzati sono risultati negativi per la presenza di Salmonella spp; mentre nei tre corsi d'acqua i livelli di HAdV raggiungono mediamente le 107 CG/10L. Nel fosso Fiumetto la concentrazione virale oscilla tra 4.54 x 106 e 1.31 x 108 CG/10L ;nel fosso Motrone la concentrazione oscilla tra 7.75 x 106 e 2.81 x 108 CG/10L e infine nella fossa dell'Abate la concentrazione varia tra un minimo di 6.82 x 105 e 3.85 x 108 CG/10L

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 \ub0C and 36 \ub0C, 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 Minist\ue8re de la Sant\ue9 et des Solidarit\ue9s (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

Biofilm growth on orthopedic implantable materials: static or dynamic condition what is the most appropriate methodological tools to study device-related infections?

Aim Study of biofilm growth under static and dynamic conditions to evaluate the most suitable orthopedic materials on the prevention of device-related infections. Method Biofilms of Staphylococcus epidermidis (ATCC 35984) icaA and icaD genes positive and Pseudomonas aeruginosa (DSM 939) were generated under static and dynamic conditions, adding the bacterial inocula on titanium, carbon, polycarbonate and carbon-peek coupons housed in flat bottom test tubes or in the CDC Biofilm Reactor (CBR) system respectively. Biofilm growth was evaluated by MTT assay after 48 hours. Results Results of dynamic model showed a better capacity of S.epidermidis to grow with a rotation between 120-60 rpm on each tested materials (Mann-Whitney test, p-value < 0,05) than P.aeruginosa. Titanium was thematerial on which the bacterial strains adhered less, whereas carbon and polycarbonate allowed greatest adherence of P.aeruginosa (Mann-Whitney test, p-value < 0,05). Results of static model showed that both species grew on each materials without distinction (Kruskal-Wallis test, p-value 0,95). S.epidermidis growth was better also under static condition. Conclusions the static model was not able to evaluate the different adhesion capacity of the strains to the materials, confirming the dynamic model is the most suitable tool for the study of orthopedic materials on the prevention of device-related infections. This research was funded by the University of Pisa, PRA 2017_18 Projec

Application of hydrogen peroxide as an innovative method of treatment for Legionella control in a hospitalwater network

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; Legionella pneumophila 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

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&ndash;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 &gt;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

Role of Hydrogen Peroxide Vapor (HPV) for the Disinfection of Hospital Surfaces Contaminated by Multiresistant Bacteria

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 topi

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

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

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

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&ndash;37 &deg;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&ndash;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 &times; 102 CFU/m3) to the post-aerosolizing samples (mean 1.5 &times; 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