Evaluation of standardized sample collection, packaging, and decontamination procedures to assess cross-contamination potential during Bacillus anthracis incident response operations

The Evaluation of Physiological Index Changes and Safety Work of Female Medical Staff With Different Medical Protection Standards in the Ward of COVID-19

Background

Effective personal protective equipment (PPE) contribute to the prevention of COVID-19 infection. However, it is necessary to evaluate the potential risk of different medical protections in the isolation ward of COVID-19.

Objectives

We aimed to explore the dynamics in physiological indexes of medical staff under primary and secondary PPE in the isolation ward of COVID-19 and provide the scientific basis for determining the safe work strategy.

Materials and Methods

In this study, 30 female nurses were selected to simulate medical work under the primary or secondary PPE, respectively. The oral temperature, axillary temperature, heart rate, respiratory rate, blood oxygen saturation, and blood pressure were measured and recorded every 20 min. The subjective adverse symptoms were recorded every 30 min. The blood glucose and weight of the individuals were measured and recorded before and after the trial.

Results

The results indicated that the median trial persistence time in the participants with moderate-intensity work wearing the secondary PPE (70.0 min) was much lower than that with moderate-intensity work wearing the primary PPE (180 min) and with light-intensity work wearing the primary PPE (110 min; p < 0.05). Importantly, the heart rate, oral/axillary temperature, and respiratory rate of physiological indexes of the participants under moderate-intensity work wearing the secondary PPE increased significantly faster than the primary PPE (p < 0.001), while blood oxygen saturation decreased significantly faster than the primary PPE (p < 0.001). In addition, the proportions of subjective adverse symptoms (such as dry mouth, dizziness, palpitations, and anhelation) were much higher than primary PPE (p < 0.001). The average sweat volume and blood glucose consumption of participants under moderate-intensity work wearing primary PPE were higher than secondary PPE (p < 0.001).

Conclusion

The combination of an exacerbated workload and secondary PPE worn by COVID-19 healthcare workers increases the change in physiological indicators, and in some cases the adverse symptoms, which can affect and even suspend their medical work. For any medical institution, there is room for improvement in terms of bioethics of a "Job Well Done" to reduce the risks of medical activities under secondary PPE.

Factors Affecting the Decontamination Process in Hospitals in Saudi Arabia

Introduction

Hospitals face various types of disasters that require either decontamination or disinfection interventions. These contaminants can be chemical, biological, radioactive, or infectious, such as COVID-19. Further, there are few studies in the literature on factors affecting decontamination in hospitals in Saudi Arabia.

Methods

Approximately 157 healthcare providers (doctors, nurses, and other specialists) participated in this study. Principle component analysis was used to explore three factors in Saudi Arabia that affect the ability of healthcare providers to decontaminate appropriately.

Results

Three factors were extracted: (1) having adequate skills to perform decontamination, (2) being adequately prepared for decontamination before a disaster occurs, and (3) organizational barriers to decontamination. There was a positive correlation between the skills and preparedness and a negative correlation between barriers and both skills and preparedness.

Discussion

It is essential to prepare for decontamination during disasters more effectively and to ensure that all healthcare providers have the requisite skills. Moreover, barriers to decontamination must be investigated thoroughly to improve implementation.

Decontamination of Personal Protective Equipment

Exploratory field analyses of the inactivation capacity of disinfectants on contaminated personal protective equipment (PPE) are required to select a suitable surrogate for biohazardous agents like spores of Bacillus anthracis. The objectives of our study were (1) the determination of an appropriate surrogate for the inactivation of spores of B. anthracis with peracetic acid (PAA), and (2) application of optimized inactivation conditions for an effective decontamination of PPE with PAA under field conditions. For inactivation studies, B. anthracis spores from different strains and B. thuringiensis spores were fixed by air drying on carriers prepared from PPE fabric. Time and concentration studies with PAA-based disinfectants revealed that the spores of the B. thuringiensis strain DSM 350 showed an inactivation profile comparable to that of the spores of the B. anthracis strain with the highest stability, implying that B. thuringiensis can serve as an appropriate surrogate. Rapid (3 to 5 minutes) and effective surface decontamination was achieved with 2% PAA/0.2% surfactant. In field studies, PPE contaminated with spores of B. thuringiensis was treated with the disinfectant. Optimizing the decontamination technique revealed that spraying in combination with brushing was effective within 5 minutes of exposure.

Metabolic fatigue in resuscitators using personal protection equipment against biological hazard

OBJECTIVES

To describe the effects of wearing individual protection equipment against biological hazard when performing a simulated resuscitation.

METHODS

Uncontrolled quasi-experimental study involving 47 volunteers chosen by random sampling stratified by sex and professional category. We determined vital signs, anthropometric parameters and baseline lactate levels; subsequently, the volunteers put on level D individual protection equipment against biological hazard and performed a simulated resuscitation for 20 minutes. After undressing and 10 minutes of rest, blood was extracted again to determine lactate levels. Metabolic fatigue was defined as a level of lactic acid above 4 mmol/L at the end of the intervention.

RESULTS

25.5% of the participants finished the simulation with an unfavorable metabolic tolerance pattern. The variables that predict metabolic fatigue were the level of physical activity and bone mass -in a protective form- and muscle mass. People with a low level of physical activity had ten times the probability of metabolic fatigue compared to those with higher levels of activity (44% versus 4.5%, respectively).

CONCLUSIONS

Professionals who present a medium or high level of physical activity tolerate resuscitation tasks better with a level D individual biological protection suit in a simulated resuscitation.

Does Gender Influence Physiological Tolerance in Resuscitators When Using Personal Protection Equipment against Biological Hazards?

Introduction

Certain professions, such as those related to emergency services, have usually been performed by men, progressively incorporating women into these professions. The main objective of our study was to determine, according to gender, how the use of level D biohazard personal protection equipment (PPE) affects emergency professionals during the performance of resuscitation.

Materials and Methods

An uncontrolled quasi-experimental study was performed on 96 volunteers selected by means of random sampling stratified by gender. Baseline and final vital signs of the assessment activity were analyzed. This activity involves volunteers performing a simulated resuscitation in a controlled environment whilst wearing personal protective suits in a biohazard situation.

Results

Analyzing the physiological tolerance pattern parameter by parameter, and according to gender, through a univariate model, we can observe that there is no interaction between tolerance and gender; that is, having good or bad tolerance does not depend on gender. Conclusion. This specialized skilled work can be performed by any properly trained professional.

Evaluation of Commercial-off-the-Shelf Materials for the Preservation of Bacillus anthracis Vegetative Cells for Forensic Analysis

Environmental surface sampling is crucial in determining the zones of contamination and overall threat assessment. Viability retention of sampled material is central to such assessments. A systematic study was completed to determine viability of vegetative cells under nonpermissive storage conditions. Despite major gains in nucleic acid sequencing technologies, initial positive identification of threats must be made through direct culture of the sampled material using classical microbiological methods. Solutions have been developed to preserve the viability of pathogens contained within clinical samples, but many have not been examined for their ability to preserve biological agents. The purpose of this study was to systematically examine existing preservation materials that can retain the viability of Bacillus anthracis vegetative cells stored under nonpermissive temperatures. The results show effectiveness of five of seventeen solutions, which are capable of retaining viability of a sporulation deficient strain of B. anthracis Sterne when stored under nonrefrigerated conditions.