-
ACS Applied Bio Materials Mar 2023Effective cleaning and disinfection procedures are an integral part of good manufacturing practice and in maintaining hygiene standards in health-care facilities. In...
Effective cleaning and disinfection procedures are an integral part of good manufacturing practice and in maintaining hygiene standards in health-care facilities. In this study, a method to validate such cleaning and disinfection procedures of surfaces was established employing lipid nanoparticles (LNPs) encapsulating DNA. It was possible to determine and distinguish between the physical cleaning effect (dilution) and the chemical cleaning effect (disintegration) on the LNPs during the cleaning and disinfection procedure (wiping). After treatment with 70 v % ethanol as a disinfectant and SDS solution as a cleaning agent, LNPs showed log reductions of 4.5 and 4.0, respectively. These values are similar to the log reductions exhibited by common bacteria, such as and Therefore, LNPs pose as useful tools for cleaning validation with advantages over the already existing tools and enable a separate detection of dilution and chemical disinfectant action.
Topics: Disinfection; Disinfectants; Liposomes; Ethanol; Escherichia coli; DNA
PubMed: 36854082
DOI: 10.1021/acsabm.3c00004 -
Sensors (Basel, Switzerland) Jul 2022The quality of the drinking water distributed through the networks has become the main concern of most operators. This work focuses on one of the most important...
The quality of the drinking water distributed through the networks has become the main concern of most operators. This work focuses on one of the most important variables of the drinking water distribution networks (WDN) that use disinfection, chlorine. This powerful disinfectant must be dosed carefully in order to reduce disinfection byproducts (DBPs). The literature demonstrates researchers' interest in modelling chlorine decay and using several different approaches. Nevertheless, the full-scale application of these models is far from being a reality in the supervision of water distribution networks. This paper combines the use of validated chlorine prediction models with an intensive study of a large amount of data and its influence on the model's parameters. These parameters are estimated and validated using data coming from the Supervisory Control and Data Acquisition (SCADA) software, a full-scale water distribution system, and using off-line analytics. The result is a powerful methodology for calibrating a chlorine decay model on-line which coherently evolves over time along with the significant variables that influence it.
Topics: Chlorine; Disinfectants; Disinfection; Drinking Water; Water Pollutants, Chemical; Water Purification
PubMed: 35898083
DOI: 10.3390/s22155578 -
American Journal of Infection Control Feb 2019Halting the spread of harmful microbes requires an understanding of their transmission via hands and fomites. Previous studies explored acute and long-term care...
BACKGROUND
Halting the spread of harmful microbes requires an understanding of their transmission via hands and fomites. Previous studies explored acute and long-term care environments but not outpatient clinics. Objectives of this study were to track microbial movement throughout an outpatient clinic and evaluate the impact of a disinfectant spray intervention targeting high-touch point surfaces.
METHODS
At the start of the clinic day, a harmless viral tracer was placed onto 2 fomites: a patient room door handle and front desk pen. Patient care, cleaning, and hand hygiene practices continued as usual. Facility fomites (n = 19), staff hands (n = 4), and patient hands (n = 3-4) were sampled after 2, 3.5, and 6 hours. Tracer concentrations at baseline (before intervention) were evaluated 6 hours after seeding. For the intervention trials, high-touch surfaces were cleaned 4 hours after seeding with an ethanol-based disinfectant and sampled 2 hours after cleaning.
RESULTS
At 2, 3.5, and 6 hours after seeding, virus was detected on all surfaces and hands sampled, with examination room door handles and nurses' station chair arms yielding the highest concentrations. Virus concentrations decreased by 94.1% after the disinfectant spray intervention (P = .001).
CONCLUSIONS
Microbes spread quickly in an outpatient clinic, reaching maximum contamination levels 2 hours after inoculation, with the highest contamination on examination room door handles and nurses' station chairs. This study emphasizes the importance of targeted disinfection of high-touch surfaces.
Topics: Aerosols; Ambulatory Care Facilities; Disease Transmission, Infectious; Disinfectants; Disinfection; Ethanol; Fomites; Humans
PubMed: 30195405
DOI: 10.1016/j.ajic.2018.06.017 -
Archivum Immunologiae Et Therapiae... Aug 2012This review focuses on the antibacterial activities of visible light-responsive titanium dioxide (TiO(2)) photocatalysts. These photocatalysts have a range of... (Review)
Review
This review focuses on the antibacterial activities of visible light-responsive titanium dioxide (TiO(2)) photocatalysts. These photocatalysts have a range of applications including disinfection, air and water cleaning, deodorization, and pollution and environmental control. Titanium dioxide is a chemically stable and inert material, and can continuously exert antimicrobial effects when illuminated. The energy source could be solar light; therefore, TiO(2) photocatalysts are also useful in remote areas where electricity is insufficient. However, because of its large band gap for excitation, only biohazardous ultraviolet (UV) light irradiation can excite TiO(2), which limits its application in the living environment. To extend its application, impurity doping, through metal coating and controlled calcination, has successfully modified the substrates of TiO(2) to expand its absorption wavelengths to the visible light region. Previous studies have investigated the antibacterial abilities of visible light-responsive photocatalysts using the model bacteria Escherichia coli and human pathogens. The modified TiO(2) photocatalysts significantly reduced the numbers of surviving bacterial cells in response to visible light illumination. They also significantly reduced the activity of bacterial endospores; reducing their toxicity while retaining their germinating abilities. It is suggested that the photocatalytic killing mechanism initially damages the surfaces weak points of the bacterial cells, before totally breakage of the cell membranes. The internal bacterial components then leak from the cells through the damaged sites. Finally, the photocatalytic reaction oxidizes the cell debris. In summary, visible light-responsive TiO(2) photocatalysts are more convenient than the traditional UV light-responsive TiO(2) photocatalysts because they do not require harmful UV light irradiation to function. These photocatalysts, thus, provide a promising and feasible approach for disinfection of pathogenic bacteria; facilitating the prevention of infectious diseases.
Topics: Anti-Bacterial Agents; Bacteria; Catalysis; Disinfectants; Disinfection; Humans; Light; Microbial Viability; Photochemical Processes; Photosensitizing Agents; Spores, Bacterial; Titanium
PubMed: 22678625
DOI: 10.1007/s00005-012-0178-x -
Journal of Microbiology and... Jul 2021To prevent the outbreak of infectious diseases that inflict huge economic and social losses, domestic livestock farms and related facilities have introduced automatic...
To prevent the outbreak of infectious diseases that inflict huge economic and social losses, domestic livestock farms and related facilities have introduced automatic and semiautomatic disinfectant solution-spraying systems for vehicles. However, the facility standards and specifications vary by manufacturer, and no scientific performance evaluation has been conducted. The puropose of this study is to develop physical and biological evaluation methods. Physical and biological appraisals were conducted using two types of disinfection facilities (tunnel- and U-type) and two types of vehicles (passenger car, truck). Water-sensitive paper was used to evaluate the physical performance values for the disinfection facilities. In addition, to assess their biological performance, carriers containing low-pathogenic avian influenza virus were attached to vehicles, and the viral reduction was measured after the vehicles moved through the facility. The tunnel-type had rates of coverage in the range of 70-90% for the passenger car and 60-90% for the truck. At least 4-log virus reduction after spraying for 1-5 min was shown for both vehicles. For the U-type facility evaluation, the coverage rates were in the range of 60-90% for the passenger car and at least 90% for the truck. More than 4-log viral reduction was estimated within a spraying time of 5 min. To reduce viruses on the surface of vehicles by at least 4 log within a short period, the disinfectant solution should cover at least 71% of the pathogens. In conclusion, we were able to assess the physical and biological performance criteria for disinfection facilities aboard transportation vehicles.
Topics: Animals; Chickens; Disinfectants; Disinfection; Evaluation Studies as Topic; Influenza A virus; Motor Vehicles
PubMed: 34099600
DOI: 10.4014/jmb.2103.03024 -
Viruses May 2019In recent years, a new potential measure against foodborne pathogenic bacteria was rediscovered-bacteriophages. However, despite all their advantages, in connection to... (Review)
Review
In recent years, a new potential measure against foodborne pathogenic bacteria was rediscovered-bacteriophages. However, despite all their advantages, in connection to their widespread application in the food industry, negative consequences such as an uncontrolled phage spread as well as a development of phage resistant bacteria can occur. These problems are mostly a result of long-term persistence of phages in the food production environment. As this topic has been neglected so far, this article reviews the current knowledge regarding the effectiveness of disinfectant strategies for phage inactivation and removal. For this purpose, the main commercial phage products, as well as their application fields are first discussed in terms of applicable inactivation strategies and legal regulations. Secondly, an overview of the effectiveness of disinfectants for bacteriophage inactivation in general and commercial phages in particular is given. Finally, this review outlines a possible strategy for users of commercial phage products in order to improve the effectiveness of phage inactivation and removal after application.
Topics: Bacteriophages; Disinfectants; Disinfection; Food Microbiology
PubMed: 31121941
DOI: 10.3390/v11050468 -
The Science of the Total Environment Nov 2022Thermal spas are gaining more and more popularity among the population because they are used for recreational purposes. Disinfecting these baths without losing the...
Thermal spas are gaining more and more popularity among the population because they are used for recreational purposes. Disinfecting these baths without losing the health benefits poses a challenge for swimming pool operators. Previous studies have mainly focused on regulated chlorinated DBPs in freshwater pools with no bromide or seawater pools with very high bromide content. Thermal water pools have a low bromide content and in combination with chlorine can lead to chlorinated, brominated and mixed halogenated DBP species. The occurrence of brominated and mixed halogenated DBPs in these types of pools is largely unexplored, with very few or limited studies published on regulated DBPs and even fewer on emerging DBP classes. In the field of swimming pool water disinfection, apart from extensive studies in the field of drinking water disinfection, only a few studies are known in which >39 halogenated and 16 non-halogenated disinfection by-products, including regulated trihalomethanes (THM) and haloacetic acids (HAA), were investigated in swimming pool water. Calculated bromine incorporation factor (BIF) demonstrated that even small amounts of bromide in swimming pool water can lead to a large shift in DBP species towards brominated and mixed halogenated DBPs. Dihaloacetonitriles (DHANs) accounted for >50% of the calculated cytotoxicity and genotoxicity on average. Comparison of the target analysis with the TOX showed that a major part of the measured TOX (69% on average) could be explained by the regulated classes THMs, HAAs, and the unregulated class of HANs. This study aims to help operators of swimming pools with bromide-containing water to gain a better understanding of DBP formation in future monitoring and to fill the knowledge gap that has existed so far on the occurrence of DBPs in thermal water pools.
Topics: Chlorine; Disinfectants; Disinfection; Drinking Water; Halogenation; Swimming Pools; Trihalomethanes; Water Pollutants, Chemical; Water Purification
PubMed: 35843322
DOI: 10.1016/j.scitotenv.2022.157338 -
BMC Infectious Diseases Mar 2002In 2000, the World Health Organization (WHO) had eight sets of conflicting recommendations for decontaminating medical equipment. We conducted a systematic review of... (Comparative Study)
Comparative Study Review
BACKGROUND
In 2000, the World Health Organization (WHO) had eight sets of conflicting recommendations for decontaminating medical equipment. We conducted a systematic review of observational studies to assist WHO in reconciling the various guidelines. This paper summarises the methods developed and illustrates the results for three procedures--alcohol, bleach and povidone iodine.
METHODS
We developed a Medline search strategy and applied inclusion criteria specifying the decontamination procedures of interest and an outcome of microbial destruction for a set of marker organisms. We developed protocols to assess the quality of studies and categorised them according to the reliability of the methods used. Through an iterative process we identified best practice for the decontamination methods and key additional factors required to ensure their effectiveness. We identified 88 published papers for inclusion, describing 135 separate studies of decontamination.
RESULTS
For disinfection with alcohol, best practice was identified from 23 studies as an exposure to 70-80% ethanol or isopropanol for at least 5 minutes. Bleach was effective for sterilization at a concentration of 5000 ppm for 5 minutes and for disinfection at 1000 ppm for 10 minutes (33 studies). Povidone iodine was only partially effective for disinfection at a concentration of 1% for 15 minutes (15 studies).
CONCLUSIONS
Our findings provide an evidence base for WHO guidelines on decontaminating medical equipment. The results support the recommended use of bleach and show that alcohol could be used more widely than current guidelines suggest, provided best practice is followed. The effectiveness of povidone iodine is uncertain.
Topics: 2-Propanol; Disinfectants; Disinfection; Durable Medical Equipment; Ethanol; Infection Control; Povidone-Iodine; Sodium Hypochlorite; Time Factors
PubMed: 11916458
DOI: 10.1186/1471-2334-2-4 -
The Science of the Total Environment Jun 2023Chlorination of water results in the formation of haloacetic acids (HAAs) as major disinfection byproducts (DBPs). Previous studies have reported some HAAs species to...
Chlorination of water results in the formation of haloacetic acids (HAAs) as major disinfection byproducts (DBPs). Previous studies have reported some HAAs species to act as cytotoxic, genotoxic, and carcinogenic. This work aimed at further exploring the toxicity potential of the most investigated HAAs (chloroacetic (CAA), bromoacetic (BAA), iodoacetic (IAA) acid) and HAAs species with high content of bromine (tribromoacetic acid (TBAA)), and iodine in their structures (chloroiodoacetic (CIAA) and diiodoacetic acid (DIAA)) to human cells. Novel knowledge was generated regarding cytotoxicity, oxidative stress, endocrine disrupting potential, and genotoxicity of these HAAs by using human placental and lung cells as in vitro models, not previously used for DBP assessment. IAA showed the highest cytotoxicity (EC: 7.5 μM) and ability to generate ROS (up to 3-fold) in placental cells, followed by BAA (EC: 20-25 μM and 2.1-fold). TBAA, CAA, DIAA, and CIAA showed no significant cytotoxicity (EC > 250 μM). All tested HAAs decreased the expression of the steroidogenic gene hsd17b1 up to 40 % in placental cells, and IAA and BAA (0.01-1 μM) slightly inhibited the aromatase activity. HAAs also induced the formation of micronuclei in A549 lung cells after 48 h of exposure. IAA and BAA showed a non-significant increase in micronuclei formation at low concentrations (1 μM), while BAA, CAA, CIAA and TBAA were genotoxic at exposure concentrations above 10 μM (100 μM in the case of DIAA). These results point to genotoxic and endocrine disruption effects associated with HAA exposure at low concentrations (0.01-1 μM), and the usefulness of the selected bioassays to provide fast and sensitive responses to HAA exposure, particularly in terms of genotoxicity and endocrine disruption effects. Further studies are needed to define thresholds that better protect public health.
Topics: Pregnancy; Humans; Female; Placenta; Acetates; Disinfection; DNA Damage; Disinfectants; Water Pollutants, Chemical; Water Purification; Halogenation; Trihalomethanes
PubMed: 36963690
DOI: 10.1016/j.scitotenv.2023.162981 -
Food and Environmental Virology Jun 2022The worldwide COVID-19 pandemic has brought significant consideration toward innovative strategies for overcoming the viral spread. Nanotechnology will change our lives... (Review)
Review
The worldwide COVID-19 pandemic has brought significant consideration toward innovative strategies for overcoming the viral spread. Nanotechnology will change our lives in several forms as its uses span from electronics to pharmaceutical procedures. The use of nanoparticles provides a possibility to promote new antiviral treatments with a low possibility of increasing drug resistance compared to typical chemical-based antiviral treatments. Since the long-term usage of disinfectants and antiseptics at high concentrations has deleterious impacts on well-being and the environment, this review was intended to discuss the antiviral activity of disinfectants and antiseptics required for their activity against respiratory viruses especially SARS-CoV-2. It could improve the inhibition of viral penetration into cells, solvation of the lipid bilayer envelope, and ROS production, therefore enhancing the effect of disinfectants. However, significant concerns about nanomaterial's hazardous effects on individuals and the environment are increasing as nanotechnology flourishes. In this review, we first discuss the significant and essential types of nanomaterials, especially silver and copper, that could be used as antiviral agents and their viral entry mechanisms into host cells. Further, we consider the toxicity on health, and environmental concerns of nanoparticles. Eventually, we present our outlook on the fate of nanomaterials toward viral diseases.
Topics: Anti-Infective Agents, Local; Antiviral Agents; COVID-19; Disinfectants; Disinfection; Humans; Nanostructures; Pandemics; SARS-CoV-2
PubMed: 35266117
DOI: 10.1007/s12560-022-09517-0