RESUMO
AIMS: An effective decontamination procedure of personnel wearing personal protective equipment is required by CBRN responders and healthcare workers when dealing with biological warfare agents or natural outbreaks caused by highly contagious pathogens. This study aimed to identify critical factors affecting the efficacy of peracetic acid (PAA)-based disinfectants and products containing either hydrogen peroxide or sodium hypochlorite under the same conditions. METHODS AND RESULTS: The influence of concentration, application (contact) time, erroneous human behaviour, interfering substance, technical assets and weather conditions on disinfection efficacy against Bacillus subtilis spores were assessed in 14 experimental groups. Residual contamination of protective suits was measured to provide responders with readily understandable information (up to 100 colony forming units classified a suit as disinfected). Weather conditions, short application time and erroneous human behaviour substantially affected the effectiveness of PAAs (P < 0·05). Non-PAA-based disinfectants (either liquid or foam) did not reach comparable efficacy (P < 0·001). CONCLUSIONS: Peracetic acid was effective at a concentration of 6400-8200 ppm and an application time of 4 min. SIGNIFICANCE AND IMPACT OF THE STUDY: The study provides operationally relevant data for the use of PAA-based disinfectants in preparedness planning and management of biological incidents and natural outbreaks.
Assuntos
Descontaminação , Desinfetantes , Ácido Peracético , Equipamento de Proteção Individual , Desinfetantes/farmacologia , Desinfecção , Pessoal de Saúde , Humanos , Peróxido de Hidrogênio/farmacologia , Ácido Peracético/farmacologia , Equipamento de Proteção Individual/microbiologia , Esporos BacterianosRESUMO
A decontamination process plays a key role in management of biological incidents. While decontamination of surfaces and buildings located in the hot zone can be usually postponed until an agent is confirmed and an adequate planning phase is established, personnel wearing personal protective equipment must be decontaminated prior to their final exit from the hot zone. Because CBRN units require the shortest possible duration of this procedure, many factors must be considered, including concentration of biological agents, precleaning, disinfectant formulae, its concentration and spectrum of efficacy, contact time, external conditions (temperature, pH, relative humidity, soil load), technical assets used for decontamination, decontaminated surface (compatibility, pores), and staff performance. Experimental tests with surrogates of biological agents are thus necessary to identify above-mentioned points. Once an optimal decontamination procedure is recognized, a field rehearsal must follow and the method using a surrogate must be implemented into a training process of CBRN units.
Assuntos
Controle de Doenças Transmissíveis/métodos , Descontaminação , Meio Ambiente , Microbiologia Industrial/métodos , Fatores Biológicos , Desinfetantes , HumanosRESUMO
In patients with alcoholic cardiomyopathy there is evidence that mild heart failure is reversible if patients abstain from alcohol, but there is no consensus whether the disease is progressive once structural myocardial dilation has evolved. The aim of the present study was to compare the long-term course of congestive heart failure due to alcoholic and idiopathic dilated cardiomyopathy. Of 75 patients with overt congestive heart failure, 23 had alcoholic cardiomyopathy and were compared to 52 patients with idiopathic cardiomyopathy. The mean age was 48 +/- 12 years. Despite medical therapy, heart failure class New York Heart Association III-IV was present in 52% of patients with alcoholic and 47% of patients with idiopathic cardiomyopathy (not significant). Their mean left ventricular ejection fraction was 30 +/- 12% vs 28 +/- 12% and left ventricular end-diastolic volumes were 264 +/- 125 ml and 254 +/- 100 ml respectively (not significant). Overall survival at 1, 5 and 10 years was 100%, 81% and 81% for the group with alcoholic dilated cardiomyopathy and 89%, 48% and 30% for the group with idiopathic cardiomyopathy, respectively (P = 0.041), and the difference was even greater for transplant-free survival P = 0.005). Clinical and invasive signs of left and right heart failure as well as left ventricular dimensions were predictive of a fatal outcome; however, symptom duration and left ventricular volumes were only predictive in patients with idiopathic cardiomyopathy, suggesting that in the two patient groups different mechanisms may lead to death. Mortality in patients with severe congestive heart failure and left ventricular dilatation due to alcoholic cardiomyopathy is significantly lower than that in patients with idiopathic cardiomyopathy and similar degrees of heart failure. Thus, despite structural changes inherent in marked left ventricular dilatation, disease progression in alcoholic dilated cardiomyopathy is different from that in idiopathic cardiomyopathy and thus may have implications for the choice of therapy.