Raman microscopic analysis of dry-surface biofilms on clinically relevant materials

Moist/hydrated biofilms have been well-studied in the medical area, and their association with infections is widely recognized. In contrast, dry-surface biofilms (DSBs) on environmental surfaces in healthcare settings have received less attention. DSBs have been shown to be widespread on commonly used items in hospitals and to harbor bacterial pathogens that are known to cause healthcare-acquired infections (HAI). DSBs cannot be detected by routine surface swabbing or contact plates, and studies have shown DSBs to be less susceptible to cleaning/disinfection products. As DSBs are increasingly reported in the medical field, and there is a likelihood they also occur in food production and manufacturing areas, there is a growing demand for the rapid in situ detection of DSBs and the identification of pathogens within DSBs. Raman microspectroscopy allows users to obtain spatially resolved information about the chemical composition of biofilms, and to identify microbial species. In this study, we investigated Staphylococcus aureus mono-species DSB on polyvinylchloride blanks and stainless steel coupons, and dual-species (S. aureus/Bacillus licheniformis) DSB on steel coupons. We demonstrated that Raman microspectroscopy is not only suitable for identifying specific species, but it also enables the differentiation of vegetative cells from their sporulated form. Our findings provide the first step towards the rapid identification and characterization of the distribution and composition of DSBs on different surface areas

Containing the burden of infectious diseases is everyone’s responsibility.:A call for an integrated strategy for developing and promoting hygiene behaviour change in home and everyday life

Across the world, health agencies recognize the profound impact of infectious disease on health and prosperity. Equally, they recognize that prevention is central to fighting infection, and that hygiene in home and everyday life (HEDL) is a key part of this. A current driver is the part that hygienei plays in tackling antibiotic resistance, but it also reflects growing numbers of people at greater risk of infection being cared for in the community. Sustaining the quality of state-funded healthcare requires that the public take greater responsibility for their own health, including protecting themselves and their families against infection. Hygiene must be must be everyone’s responsibility. However, if we are to be successful in promoting hygiene as part of public health, there are barriers which need to be overcome. A key issue is the need to balance evidence of the health benefits of hygiene against possible risks, such as environmental impacts and toxicity issues. Another issue is the role of microbes in human health and whether we have become “too clean”. Lack of a unified voice advocating for hygiene means these issues have tended to take precedence. Another barrier to change is public confusion about the need for hygiene and the difference between hygiene and cleanliness. To address this, we must work together to provide the public with a clear, consistent restatement of the importance of hygiene, and to change public perceptions about hygiene and good hygiene practice. This paper is unique because it examines these issues in an integrated manner and focuses on making achievable, constructive recommendations for developing an effective and sustainable approach. The paper lays out a risk management strategy for hygiene in home and everyday life which gives hygiene appropriate priority within the context of environmental and other health concerns. This “targeted hygiene” approach needs to be placed at the heart of a multimodal prevention strategy, alongside vaccination and other interventions. Based on the findings of this paper, we issue a call to action to national and international policy makers, health agencies and health professionals to recognize the need for an integrated, family-centredii approach to hygiene, and provide effective leadership to achieve this. This paper shows that many of the components of a behaviour change strategy are already in place, but need to be integrated rather than developed independently. We also issue a call to scientists, health professionals, environmental and regulatory agencies, immunologists, microbiomists, the private sector (hygiene appliance and product manufacturers) and the media to work together, through innovative research and communication policies. A collaborative effort is vital if we are to overcome barriers to change and action integrated behaviour change programmes that really work. The report represents the consensus views of an international, interdisciplinary group of experts in the field of infection prevention and hygiene. We recognise that this paper leaves many questions unanswered and would welcome further dialogue with stakeholders on how to develop policy. The aim of this paper is to provide a sound basis for such dialogue. At the 2016 launch of the European Human Biomonitoring Initiative, the EU commissioner for food safety said the followingiii which encapsulates the aim of this report. “We must collectively recognise that risk and uncertainty are part and parcel of every decision we take. We need to engage people in a serious and rational debate. But in this world of information overload – from old media and new – information, misinformation, opinions, prejudices, truths, half-truths and un-truths all compete for public attention. We need better communication of science so that people can be better informed about risk assessment and management decisions

Virucidal Efficacy of Laundering

Viruses contribute significantly to the burden of infectious diseases worldwide. Although there are multiple infection routes associated with viruses, it is important to break the chain of infection and thus consider all possible transmission routes. Consequently, laundering can be a means to eliminate viruses from textiles, in clinical settings well as for domestic laundry procedures. Several factors influence the survival and inactivation of microorganisms, including viruses on hard surfaces and textiles. Therefore, textiles should be regarded as potential fomites. While in clinical and industrial settings laundry hygiene is ensured by standardized processes, temperatures of at least 60 °C and the use of oxidizing agents, domestic laundry is not well defined. Thus, the parameters affecting viral mitigation must be understood and prudently applied, especially in domestic laundering. Laundering can serve as a means to break the chain of infection for viral diseases by means of temperature, time, chemistry and mechanical action

Virucidal Efficacy of Household Dishwashers

Not only since SARS-CoV-2, have transmission routes of viruses been of interest. Noroviruses e.g., can be transmitted via smear infection, are relatively stable in the environment and very resistant to chemical disinfection. Some studies determined the virucidal efficacy of laundering processes, but few studies focused on the virucidal efficacy of dishwashing processes. Here, especially consumer related conditions are of interest. Households for example are a hotspot of norovirus infection and thus a sufficient reduction of these and other viruses from dishes must be insured to avoid an infection via this route. The likelihood of such an event should not be underestimated, since it was shown that the washing machine can be a reservoir for the transmission of extended spectrum beta-lactamase producing bacteria in newborns. Although viruses do not replicate in these devices a transmission via contaminated cutlery e.g., cannot be excluded. Using a consumer related approach to determine the virucidal efficacy of dishwashers, we found a combination of a bleach containing dishwasher detergent, a cleaning temperature of 45 °C for 45 min and a rinsing temperature of 50 °C, to be sufficient to reduces viral titer of bovine corona virus, murine norovirus and modified vaccinia virus by 4.8, 4.2 and 3.8 logarithmic stages respectively

Smells Like Teen Spirit—A Model to Generate Laundry-Associated Malodour In Vitro

Although malodour formation on textiles and in washing machines has been reported to be a very relevant problem in domestic laundry, the processes leading to bad odours have not been studied intensively. In particular, the smell often described as “wet-and-dirty-dustcloth-like malodour” had not been reproduced previously. We developed a lab model based on a bacterial mixture of Micrococcus luteus, Staphylococcus hominis, and Corynebacterium jeikeium, which can produce this odour type and which might allow the detailed investigation of this problem and the development of counteractions. The model uses bacterial strains that have been isolated from malodourous textiles. We could also show that the three volatile compounds dimethyl disulfide, dimethyl trisulfide, and indole contribute considerably to the “wet-fabric-like” malodour. These substances were not only found to be formed in the malodour model but have already been identified in the literature as relevant malodourous substances

Use of Automatic Dishwashers and Their Programs in Europe with a Special Focus on Energy Consumption

Due to the current high awareness and rising energy costs, the energy label of domestic appliances is an important indicator for consumers when buying a dishwasher. However, not all consumers use efficient Eco cycles on a regular basis. When investigating the use of domestic dishwashers and the chosen programs in a survey with 6090 participants from 11 countries in Europe, it turned out that only 25% used Eco cycles regularly while the vast majority of 48% prefer to use Normal/Auto cycles. We also assessed individual energy and water consumption as well as duration and temperature of the programs. Considering the fact that Eco programs are not well accepted due to their duration, our study shows that Short programs, which on average only last about 30 min and consume little energy and water, might be an economical and convenient alternative to the more time-consuming Eco programs. In fact, some Short programs considered in this study proved to consume less energy for a full dishwasher load (0.74 kWh on average) than the standard Eco programs (0.90 kWh on average), especially due to their shorter duration, but it is important to note that, according to the manufacturer, these programs are designed for rather lightly soiled dishes

A Comprehensive View of Microbial Communities in the Laundering Cycle Suggests a Preventive Effect of Soil Bacteria on Malodour Formation

Microorganisms are an important factor in the wash-and-use cycle of textiles since they can cause unwanted aesthetic effects, such as malodour formation, and even pose health risks. In this regard, a comprehensive view of the microbial communities in washing machines and consideration of the microbial contamination of used textiles is needed to understand the formation of malodour and evaluate the infection risk related to laundering. So far, neither the compositions of washing machine biofilms leading to the formation of or protection against malodour have been investigated intensively, nor have microbial communities on used towels been analysed after normal use. Our results link the qualitative and quantitative analysis of microbial communities in washing machines and on used towels with the occurrence of malodour and thus not only allow for a better risk evaluation but also suggest bacterial colonizers of washing machines that might prevent malodour formation. It was shown that soil bacteria such as Rhizobium, Agrobacterium, Bosea, and Microbacterium in particular are found in non-odourous machines, and that Rhizobium species are able to prevent malodour formation in an in vitro model

PHOTOPROBER® Biotin: An Alternative Method for Labeling Archival DNA for Comparative Genomic Hybridization

Comparative genomic hybridization (CGH) represents a powerful method for screening the entire genome of solid tumors for chromosomal imbalances. Particularly it enabled the molecular cytogenetic analysis of archival, formalin‐fixed, paraffin‐embedded (FFPE) tissue. A well‐known dilemma, however, is the poor DNA quality of this material with fragment sizes below 1000 bp. Nick translation, the conventionally used enzymatic DNA labeling method in CGH, leads to even shorter fragments often below a critical limit for successful analysis. In this study we report the alternative application of non‐enzymatic, PHOTOPROBE® biotin labeling for conjugation of the hapten to the DNA prior to in situ hybridization and fluorescence detection. We analyzed 51 FFPE tumor samples mainly from the upper respiratory tract by both labeling methods. In 19 cases, both approaches were successful. The comparison of hybridized metaphases showed a distinct higher fluorescence signal of the PHOTOPROBE® samples sometimes with a discrete cytoplasm background which however did not interfere with specificity and sensitivity of the detected chromosomal imbalances. For further 32 cases characterized by an average DNA fragment size below 1000 bp, PHOTOPROBE® biotin was the only successful labeling technique thus offering a new option for CGH analysis of highly degraded DNA from archival material