The results of this study provide important results in the field of hydrogen peroxide decontamination when analysing the effect on spores other than those of G. stearothermophilus.

The detection of airborne pathogens is becoming a subject of great concern in modern day society. Recent studies have shown that electrostatic samplers are suitable for collecting microorganisms as well as preserving their viability. In most of these studies, flow rates were lower than 12.5 L/min or required a concentration stage to increase the flow rate to 100 L/min. In the present study, a single stage electrostatic sampler was developed for an efficient collection of microorganisms at 100 L/min. The design is based on the positive DC corona between coaxial cylinders to continuously create charged particles as they pass through the sampler. The physical collection efficiency of the device was investigated by sampling the ambient air particles. The efficiency in collecting live biological samples was determined by sampling live bacterial spores with the collector situated inside an aerosol chamber. It is shown that particles of 0.3-0.35 µm are captured with an efficiency of about 86%, whereas cultivable spores of Bacillus thuringiensis are collected with an efficiency of about 94%. Results are compared with an analytical predictive model. The experimental results are similar to the efficiencies previously reported in the literature; however, the current sampler design features a higher flow rate which enables the device to be used as an alarm trigger in a shorter period of time.

A fast, effective, and safe disinfection of personal protective equipment (PPE) is vitally important for emergency forces involved in biological hazards. This study aimed to investigate a broad range of disinfectants to improve the established disinfection procedure. We analyzed the efficacy of chlorine-, peracetic acid-, and oxygen-based disinfectants against Bacillus spores on PPE. Therefore, spores of different Bacillus species were exposed to disinfectants on PPE material by using a standardized procedure covering the dried spores with disinfectants and applying mechanical distribution. Efficacy of disinfectants was quantified by determining the reduction factor (log 10 levels) and number of viable spores left afterward. The chlorine-based granulate Hypochlorit CA G (2% chlorine) sufficiently inactivated Bacillus spores of risk groups 1 and 2, even with temperatures ranging from-20 to 35°C. Wofasteril Ò SC super (1.75% peracetic acid) achieved a reliable reduction of risk groups 1 and 2 and even fully virulent Bacillus spores by ‡5 log 10 levels on PPE. With this, Hypochlorit-CA G and Wofasteril Ò SC super proved to be promising alternatives to the previously proven and widely used peracetic acid compound Wofasteril Ò (2% peracetic acid) for the disinfection of PPE when bacterial spores are known to be the contaminating agent. These results will help to improve the disinfection of PPE during biological hazards by providing new data on promising alternative compounds.

Aims: The aim of this study was to develop a novel selective agar for the specific isolation and detection of Bacillus anthracis. Methods and Results: Based on published data on antibiotic resistance and susceptibility of B. anthracis and other closely related species of the Bacillus cereus sensu lato group, a new selective agar formulation termed CEFOMA (Bacillus CEreus sensu lato group-specific antibiotics, FOsfomycin, MAcrolides) was developed and evaluated. All tested strains of B. anthracis were able to grow on CEFOMA with the same colony number as on non-selective media, whereas CEFOMA inhibited the growth of the other species within the B. cereus sensu lato group. In comparison to other selective agars, CEFOMA had a superior performance and considerably reduced the total amount of accompanying flora in soil. Furthermore, B. anthracis was successfully isolated from deliberately spiked soil samples. Conclusions: CEFOMA is a highly promising selective agar for the efficient isolation of B. anthracis from environmental samples with a large bacterial background flora. Significance and Impact of the Study: The isolation of B. anthracis from environmental samples is severely impaired by the lack of adequate selective agars which suppress the growth of other bacteria. CEFOMA agar represents an important improvement and suitable alternative to currently used selective agars.

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