Kinetics of Bacterial Inactivation by Peroxynitric Acid in the Presence of Organic Contaminants.

Low-temperature atmospheric-pressure plasma has been studied for disinfection purposes. When plasma is exposed to water, reactive oxygen and nitrogen species are generated and preserved in the water fraction (plasma-treated water [PTW]), which consequently exhibits bactericidal activity. At low temperatures, one of the bactericidal components of PTW is peroxynitric acid (PNA). Importantly, PNA can also be synthesized by chemical reaction, without exposure to plasma. In this study, we evaluated the bactericidal properties of PNA based on reaction kinetics in comparison with other disinfectants. The analysis, based on dose-dependent effects, showed that PNA exhibited about 1 and 10 times the bactericidal activity of hypochlorous acid (HOCl) and peracetic acid, respectively. In addition, we evaluated the influence of organic contaminants on the bactericidal effects of PNA and HOCl. The bactericidal potential of both disinfectants was reduced by bovine serum albumin (BSA); however, PNA showed about 30-times-higher resistance against BSA inhibition than HOCl. Analysis of the dose-dependent effects of PNA revealed that the inhibition of bactericidal effect was caused by its consumption. Further experiments using model substrates containing particular amino acid residues (Met, Cys, Lys, and Leu) suggested that the bacterial inactivation by PNA is less affected by BSA due to the low reactivity and narrow reactivity spectrum of PNA for amino acid residues. Overall, our results suggest that PNA has a great disinfection potential, especially in the presence of organic contaminants (e.g., on the surface of the human body and on medical instruments contaminated with biological fluids).IMPORTANCE A good disinfectant for the human body should have various properties, such as strong bactericidal activity, harmlessness to living tissues, and resistance against biological fluids (or other organic contaminants). Peroxynitric acid (PNA) showed a bactericidal effect that was several tens up to several hundred times higher per unit of molarity than that of sodium hypochlorite and peracetic acid, which are used as general disinfectants for medical equipment. Moreover, the high resistance of PNA to organic load was confirmed, indicating that PNA will inactivate bacteria effectively even on contaminated surfaces, such as used medical devices or the human body surface. Therefore, we propose that PNA can be used as a strong disinfectant for the human body.

What is the current NHS service provision for patients severely affected by chronic fatigue syndrome/myalgic encephalomyelitis? A national scoping exercise.

BACKGROUND: Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME), in its most severe clinical presentation, can result in patients becoming housebound and bedbound so unable to access most available specialist services. This presents particular clinical risks and treatment needs for which the National Institute for Health and Care Excellence (NICE) advises specialist medical care and monitoring. The extent of National Health Service (NHS) specialist provision in England for severe CFS/ME is currently unknown. OBJECTIVES: To establish the current NHS provision for patients with severe CFS/ME in England. SETTING AND PARTICIPANTS: All 49 English NHS specialist CFS/ME adult services in England, in 2013. METHOD: Cross-sectional survey by email questionnaire. PRIMARY OUTCOME MEASURES: Adherence to NICE guidelines for severe CFS/ME. RESULTS: All 49 services replied (100%). 33% (16/49) of specialist CFS/ME services provided no service for housebound patients. 55% (27/49) services did treat patients with severe CFS/ME and their interventions followed the NICE guidelines. The remaining services (12%, 6/49) offered occasional or minimal support where funding allowed. There was one NHS unit providing specialist inpatient CFS/ME provision in England. CONCLUSIONS: Study findings highlight substantial variation in access to specialist care for patients with severe presentation of CFS/ME. Where treatment was provided, this appeared to comply with NICE recommendations for this patient group.