The 2014 West Africa Ebola outbreak saw a substantial number of healthcare workers (HCWs) being infected, despite the use of personal protective equipment (PPE). PPE is intended to protect HCWs when caring for patients with Ebola virus disease (EVD), but PPE may play a role in the spread of Ebola in healthcare environments. Before the removal of PPE, chemical disinfection may prevent the transfer of pathogens to HCWs, but the efficacy of common disinfectants against enveloped viruses, such as Ebola, on PPE surfaces is relatively unknown. The purpose of this study is to assess the efficacy of two common disinfectants, chlorine bleach (Clorox® bleach) and quaternary ammonium (Micro-Chem Plus®), used in healthcare settings for inactivation of enveloped viruses on PPE. The virucidal activity of the two disinfectants were tested against bacteriophage Φ6, an enveloped, non-pathogenic surrogate for enveloped viruses, on Tyvek suit surfaces. Virus was dried onto Tyvek suit surface, exposed to the disinfectants at use-dilution for a contact time of one minute, and the surviving virus was quantified using a double agar layer (DAL) assay. The Clorox® bleach and Micro-Chem Plus® produced a >3.21 log10 reduction and >4.33 log10 reduction, respectively, in Φ6 infectivity. The results of this study suggest that chlorine bleach and quaternary ammonium are effective in the inactivation of enveloped viruses on Tyvek suit surfaces. Chemical disinfection of PPE should be considered as a viable method to reduce the spread of pathogenic, enveloped viruses to HCWs, patients, and other environmental surfaces in healthcare settings.

Το πρόβληµα της διαχείρισης των ιατρικών αποβλήτων και ιδιαίτερα αυτών που χαρακτηρίζονται ως επικίνδυνα έχει οξυνθεί τα τελευταία χρόνια στην Ελλάδα. Το 10-25% των παραγόμενων ιατρικών αποβλήτων στις υγειονομικές μονάδες, θεωρούνται επικίνδυνα, με δυνατότητα πρόκλησης μίας σειράς κινδύνων για την υγεία, σε περίπτωση επαφής ή έκθεσης σε αυτά, διότι αποτελούν στις περισσότερες των περιπτώσεων φορείς παθογόνων µικροοργανισµών µε αποτέλεσµα η µη ασφαλής διάθεσή τους να εγκυμονεί σηµαντικότατους κινδύνους, όχι µόνο για το περιβάλλον, αλλά και για τη δηµόσια υγεία. Αντικείμενο της παρούσας εργασίας αποτελεί η μελέτη και η αξιολόγηση μεθόδων επεξεργασίας των επικίνδυνων ιατρικών απορριμμάτων. Ο όρος αξιολόγηση αναφέρεται στην διαδικασία επιλογής της κατάλληλης τεχνολογίας επεξεργασίας, λαμβάνοντας υπόψιν πληθώρα παραγόντων. Οι πιο διαδεδομένες μέθοδοι που θα εξεταστούν, είναι η αποτέφρωση, η αποστείρωση, η απολύμανση με μικροκύματα και η χημική απολύμανση. Σκοπός της εργασίας είναι να καταστήσει σαφές το ότι καμία μέθοδος δεν αποτελεί πανάκεια. Αντιθέτως, πρέπει να γίνεται προσεκτική επιλογή της μεθόδου, πάντα με σεβασμό στην υγεία και το περιβάλλον. / The problem of medical waste management, and especially of that which is characterized as hazardous, has increased in Greece during the last years. Hazardous medical waste is 10-25% of the total quantity of medical waste that is produced in health units. In most cases, this type of medical waste is carrier of pathogenic microorganisms. Thus, its ineffective way of disposal puts in danger the environment and the public health. This thesis is an assessment of different technologies that can manage hazardous medical waste. The term assessment refers to the choice of the appropriate technology, taking into account many different factors. The most widely used methods are incineration, sterilization, disinfection with microwave irradiation and chemical disinfection. Aim of this thesis is to make clear that there is not any technology that is really effective with all types of hazardous medical waste. Thus, we have to carefully choose the appropriate technology, always with respect to health and the environment.

Made available in DSpace on 2014-08-20T14:30:13Z (GMT). No. of bitstreams: 1 Tese_Gloria_Beatriz_Azevedo_Cubas.pdf: 1660996 bytes, checksum: 8bb44113acc263526d63d6f5e7e47e2b (MD5) Previous issue date: 2012-12-07 / The aims of this randomised controlled trial were to evaluate the influence of a preprocedural 0.12% chlorhexidine mouthrinse on the microbial contamination of dental impressions, subsequently disinfected with sodium hypoclorite or water (control). The second objective was to evaluate if aqueous solution of 0.12% chlorhexidine mixed with irreversible hydrocolloid powder would decrease microbial contamination of dental impressions. Forty subjects underwent maxillary dental impressions with irreversible hydrocolloid and were randomly divided into two groups (n=20) according to the preprocedural mouthrinse (0.12% chlorhexidine or placebo).The dental impressions were then divided into two subgroups and disinfected with sodium hypochlorite or water (control). In the second part, 20 subjects underwent maxillary dental impressions with irreversible hydrocolloid and randomly assigned into two groups according to the mixed agent used (0.12% chlorhexidine or water). Saliva and alginate samples were assessed for microbiological counts of total micro-organisms, total streptococci and Candida species. Surface roughness of the impressions and dimensional stability of the casts were also evaluated. Chlorhexidine preprocedural mouthrinse significantly reduced (p<0.05) microbial contamination. Small but significant alterations were produced on dimensional stability and surface quality when sodium hypochlorite was used as disinfectant after the impression (p=0.005). The results also showed that the use of aqueous 0.12% chlorhexidine mixed with the powder of irreversible hydrocolloid decreased the percentage of total micro-organisms and total Streptococci counts (p<0.001), without producing alterations in surface quality and dimensional stability. It can be concluded that 0.12% chlorhexidine used as preprocedural mouthrinse, or mixed with irreversible hydrocolloid powder, are effective methods in reducing microbial contamination of alginate impressions, without causing damage to the physical and mechanical properties of the material / Os objetivos deste ensaio clínico randomizado foram (I) avaliar a influência de um bochecho, com solução de clorexidina 0,12% e placebo, previamente a realização de moldagens bucais, posteriormente desinfetadas com hipoclorito de sódio ou água (controle) na contaminação de moldagens de alginato; e (II) avaliar se solução aquosa de clorexidina 0,12% misturada com o pó de hidrocolóide irreversível reduziria a contaminação microbiana de moldagens bucais.Quarenta voluntários foram submetidos a moldagens bucais com hidrocolóide irreversível e foram divididos de forma randomizada em 2 grupos (n=20) de acordo com a solução bucal (0,12% clorexidina ou placebo). As moldagens bucais foram divididas em 2 grupos e desinfetadas com hipoclorito de sódio ou água (controle). Na segunda parte do ensaio clinico, 20 voluntários foram submetidos a moldagens bucais com hidrocolóide irreversível e foram divididos em 2 grupos de acordo com a solução usada no preparo do alginato (0,12% clorexidina ou água).Amostras de saliva e alginato foram avaliados quanto a contagem microbiana de microrganismos totais, estreptococos totais e espécies de Candida. Rugosidade de superfície e estabilidade dimensional de modelos de gesso também foram avaliados. Bochecho com solução bucal de clorexidina reduziu de forma significativamente (p<0,005) a contaminação microbiana. Pequenas mais significativas alterações dimensionais e de rugosidade de superfície foram produzidas quando hipoclorito de sódio foi utilizado como agente desinfetante pós-moldagem (p=0,005). Os resultados também demonstraram que o uso de solução de clorexidina 0,12% misturada ao pó de hidrocolóide irreversível reduziu a percentagem de microrganismos totais e estreptococos (p<0.001), sem causar alterações de rugosidade de superfície e estabilidade dimensional. Pode ser concluído que o uso de solução de clorexidina 0,12% usada como bochecho bucal ou misturada ao pó de hidrocolóide irreversível são métodos eficientes na redução microbiana de moldagens de alginato, sem causarem danos as propriedades físicas e mecânicas do material