Health risks of pest control and disinfection workers after the COVID-19 outbreak in South Korea

The exposure patterns of pest control and disinfection workers have changed after the coronavirus disease 2019 (COVID-19) outbreak, but the health risks of chemical exposure have not been assessed. We identified these workers' chemical exposure patterns and risks before and after the COVID-19 outbreak. We used data conducted between 2018 (pre-pandemic) and 2021 (post-pandemic) from three-year cross-sectional surveys on pest control and disinfection workers. Inhalation and dermal exposure concentrations were estimated using equations based on a biocidal product risk assessment model from the Korean National Institute of Environmental Research. The non-carcinogenic and carcinogenic risks of chemicals were calculated using the United States Environmental Protection Agency risk assessment model. We found that the annual work frequency (50th percentile) of foggers using disinfectants increased the most among all the work types, from 140 uses/year to 176 uses/year after the COVID-19 outbreak. Moreover, all chemicals' non-carcinogenic and carcinogenic risks increased regardless of exposure routes. In the worst scenario (95th percentile), the margin of exposure for citric acid, benzethonium chloride, benzyl-C12-16-alkyldimethyl chlorides, and sodium chlorite of inhalation exposure, and isopropyl alcohol and benzyl-C12-16-alkyldimethyl chlorides of dermal exposure were acceptable (>100) before the COVID-19 outbreak but became unacceptable (<100) after the COVID-19 outbreak. Carcinogenic risks of dichlorvos from inhalation and dermal exposure were above acceptable levels (>10−6) before and after the COVID-19 outbreak but comparatively high after the COVID-19 outbreak. Additionally, significantly more workers experienced health symptoms after the COVID-19 outbreak (p<0.05), with the most common being muscle lethargy (31%), skin/face stinging (28.7%), and breath shortness/neck pain (24.1%).

Emergence of Tobramycin Escherichia coli resistance in poultry meat linked to biocides overuse during COVID-19

The effect of excessive use of biocides during the COVID-19, on the resistance of Escherichia coli to Tobramycin in poultry, meat was examined in this observational epidemiological study (Before and after COVID-19). Tobramycin E. coli resistant strains isolated from poultry meat before COVID-19 appearance were compared with those isolated after COVID-19 emergence. Univariable analyses were performed using t-test and chi-squared test. Odds ratios and 95% confidence intervals were used for statistically significant risk factor. Multivariate analysis was done with the binary logistic regression to detect an independent predictor, and with the principal component analysis (PCA), to analyze whether the Tobramycin resistance in E. coli was linked with the COVID-19 outbreak. Statistical significance was set at P<0.05. The frequency of Tobramycin E. coli resistant isolates was more important after COVID-19 emergence (12.5%) than before COVID-19 (2.1%). Graphical representation of PCA qualitative variables shows the interfactor relationship. A significant relationship between Tobramycin E. coli resistance and COVID-19 emergence (P=0.014), and the effect of the emergence of COVID-19 on the Tobramycin E. coli resistance was OR = 6.57 (95% Confidence interval (CI) 1.61-7.94). The probability of Tobramycin E. coli resistance linked with poultry meat bought after COVID-19 was 1.88 times more than before COVID-19 emergence. Poultry meat purchased after COVID-19 found related to Tobramycin resistance in E. coli. It seems possible that the overuse of biocides during COVID-19 increased the risk of Tobramycin E. coli resistance in poultry meat.

Increased use of sanitizers and disinfectants during the COVID-19 pandemic: identification of antimicrobial chemicals and considerations for aquatic environmental contamination

In response to the coronavirus (COVID-19) pandemic, there has been an increased need for personal and environmental decontamination to aid in curbing transmission of the SARS-CoV-2 virus. Products used for this purpose include sanitizers for hands and disinfectants for surfaces. The active chemical ingredients used in these products, termed antimicrobials, can enter waste streams after application and may be emerging as more prominent environmental contaminants. Even prior to COVID-19, there was recognized need to examine their implications for aquatic biota, which is now made more pressing due to their exaggerated use in response to the pandemic. Our objectives were to identify current antimicrobial active ingredients, quantify their increased use, and determine which may be candidates for further consideration as possible aquatic contaminants. By consulting multiple sources of publicly available information in Canada, we identified current-use antimicrobials from the lists of sanitizers and surface disinfectants approved for use against SARS-CoV-2 by Health Canada and the drug registration database. To estimate the use of sanitizers and disinfectants, we evaluated import quantities and grocery store retail sales of related compounds and products (Statistics Canada) and both lines of evidence supported increased use trends. The list of identified antimicrobials was refined to include only candidates with potential to reach aquatic ecosystems, and information on their environmental concentrations and toxicity to aquatic biota was reviewed. Candidate antimicrobials (n = 32) fell into four main categories: quaternary ammonium compounds (QACs), phenols, acids, and salts. Benzalkonium chloride, a QAC, was the most prominent active ingredient used in both nonalcohol-based hand sanitizers and surface disinfectants. Four QACs followed in prevalence and the next most used antimicrobial was triclosan (hand sanitizers only), an established and regulated environmental contaminant. Little information was found on environmental concentrations of other candidates, suggesting that the majority would fall into the category of emerging contaminants if they enter aquatic systems. Several were classified as acutely or chronically toxic to aquatic biota (Globally Harmonized System), and thus we recommend empirical research begin focusing on environmental monitoring of all candidate antimicrobials as a critical next step, with detection method development first where needed. (English) [ABSTRACT FROM AUTHOR] En réponse à la pandémie de coronavirus (COVID-19), un besoin accru de décontamination personnelle et environnementale s'est manifesté pour aider à freiner la transmission du virus SRAS-CoV-2. Les produits utilisés à cette fin comprennent des assainisseurs pour les mains et des désinfectants pour les surfaces. Les ingrédients chimiques actifs utilisés dans ces produits, appelés antimicrobiens, peuvent entrer dans les systèmes des eaux usées après leur application et peuvent devenir des contaminants environnementaux plus importants. Avant même l'avènement de la COVID-19, on reconnaissait qu'il était nécessaire d'examiner leurs implications pour le biote aquatique, ce qui est aujourd'hui rendu plus urgent en raison de leur utilisation exagérée en réponse à la pandémie. Nos objectifs consistaient à identifier les ingrédients actifs antimicrobiens actuels, à quantifier leur utilisation accrue et à déterminer ceux qui pourraient être considérés comme des contaminants aquatiques potentiels. En consultant de multiples sources d'information publiquement accessibles au Canada, nous avons pu identifiéer les antimicrobiens utilisés actuellement à partir des listes d'assainisseurs et de désinfectants de surface dont l'utilisation contre le SRAS-CoV-2 a été approuvée par Santé Canada, et de la base de données sur les produits pharmaceutiques. Pour estimer l'utilisation des assainisseurs et des désinfectants, nous avons évalué les quantités importées et les ventes au détail dans les épiceries de composés et de produits connexes (Statistique Canada) et les deux sources de données ont confirmé les tendances à l'augmentation de l'utilisation. La liste des antimicrobiens identifiés a été affinée pour n'inclure que les candidats susceptibles d'atteindre les écosystèmes aquatiques, et les informations sur leurs concentrations environnementales et leur toxicité pour le biote aquatique ont été examinées. Les antimicrobiens candidats (n = 32) se répartissent en quatre grandes catégories: les composés d'ammonium quaternaire (CAQ), les phénols, les acides et les sels. Le chlorure de benzalkonium, un CAQ, était l'ingrédient actif le plus utilisé dans les désinfectants non alcoolisés pour les mains et les désinfectants de surface. Quatre CAQ suivaient en prévalence et l'antimicrobien le plus utilisé ensuite était le triclosan (uniquement dans les désinfectants pour les mains), un contaminant environnemental avéré et réglementé. Peu d'informations sur les concentrations environnementales des autres candidats étaient accessibles, ce qui suggère que la majorité d'entre eux entreraient dans la catégorie des contaminants émergents s'ils pénètrent dans les systèmes aquatiques. Plusieurs d'entre eux ont été classés comme présentant une toxicité aiguë ou chronique pour le biote aquatique (Système général harmonisé de classification et d'étiquetage des produits chimiques, SGH). Les auteurs recommandent donc que la recherche empirique commence à se concentrer sur la surveillance environnementale de tous les candidats antimicrobiens comme prochaine étape critique, en commençant par le développement de méthodes de détection si nécessaire. Le texte intégral de l'article en français est disponible parmi les documents supplémentaires. (French) [ABSTRACT FROM AUTHOR] Copyright of Environmental Reviews is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Application of silver-based biocides in face masks intended for general use requires regulatory control.

Silver-based biocides are applied in face masks because of their antimicrobial properties. The added value of biocidal silver treatment of face masks to control SARS-CoV-2 infection needs to be balanced against possible toxicity due to inhalation exposure. Direct measurement of silver (particle) release to estimate exposure is problematic. Therefore, this study optimized methodologies to characterize silver-based biocides directly in the face masks, by measuring their total silver content using ICP-MS and ICP-OES based methods, and by visualizing the type(s) and localization of silver-based biocides using electron microscopy based methods. Thirteen of 20 selected masks intended for general use contained detectable amounts of silver ranging from 3 µg to 235 mg. Four of these masks contained silver nanoparticles, of which one mask was silver coated. Comparison of the silver content with limit values derived from existing inhalation exposure limits for both silver ions and silver nanoparticles allowed to differentiate safe face masks from face masks that require a more extensive safety assessment. These findings urge for in depth characterization of the applications of silver-based biocides and for the implementation of regulatory standards, quality control and product development based on the safe-by-design principle for nanotechnology applications in face masks in general.

Increased use of sanitizers and disinfectants during the COVID-19 pandemic: identification of antimicrobial chemicals and considerations for aquatic environmental contamination

In response to the coronavirus (COVID-19) pandemic, there has been an increased need for personal and environmental decontamination to aid in curbing transmission of the SARS-CoV-2 virus. Products used for this purpose include sanitizers for hands and disinfectants for surfaces. The active chemical ingredients used in these products, termed antimicrobials, can enter waste streams after application and may be emerging as more prominent environmental contaminants. Even prior to COVID19, there was recognized need to examine their implications for aquatic biota, which is now made more pressing due to their exaggerated use in response to the pandemic. Our objectives were to identify current antimicrobial active ingredients, quantify their increased use, and determine which may be candidates for further consideration as possible aquatic contaminants. By consulting multiple sources of publicly available information in Canada, we identified current-use antimicrobials from the lists of sanitizers and surface disinfectants approved for use against SARS-CoV-2 by Health Canada and the drug registration database. To estimate the use of sanitizers and disinfectants, we evaluated import quantities and grocery store retail sales of related compounds and products (Statistics Canada) and both lines of evidence supported increased use trends. The list of identified antimicrobials was refined to include only candidates with potential to reach aquatic ecosystems, and information on their environmental concentrations and toxicity to aquatic biota was reviewed. Candidate antimicrobials (n = 32) fell into four main categories: quaternary ammonium compounds (QACs), phenols, acids, and salts. Benzalkonium chloride, a QAC, was the most prominent active ingredient used in both nonalcohol-based hand sanitizers and surface disinfectants. Four QACs followed in prevalence and the next most used antimicrobial was triclosan (hand sanitizers only), an established and regulated environmental contaminant. Little information was found on environmental concentrations of other candidates, suggesting that the majority would fall into the category of emerging contaminants if they enter aquatic systems. Several were classified as acutely or chronically toxic to aquatic biota (Globally Harmonized System), and thus we recommend empirical research begin focusing on environmental monitoring of all candidate antimicrobials as a critical next step, with detection method development first where needed.

Unraveling the Intrinsic Biocidal Activity of the SiO2-Ag Composite against SARS-CoV-2: A Joint Experimental and Theoretical Study.

The COVID-19 pandemic has emerged as an unprecedented global healthcare emergency, demanding the urgent development of effective materials to inactivate the SARS-CoV-2 virus. This research was planned to disclose the remarkable biocidal activity of SiO2-Ag composites incorporated into low-density polyethylene. For this purpose, a joint experimental and theoretical [based on first-principles calculations at the density functional theory (DFT) level] study is performed. Biological assays showed that this material eliminatesStaphylococcus aureusand SARS-CoV-2 virus in just 2 min. Here, we investigate a previously unexplored process that we postulate may occur along the O2 and H2O adsorption and activation processes of pure and defective SiO2-Ag surfaces for the generation of reactive oxygen species (ROS). The obtained results help us to predict the nature of ROS: superoxide anion radicals, •O2-, hydroxyl radicals, •OH, and hydroperoxyl radicals, •HO2, that destroy and degrade the structure of the SARS-COV-2 virus. This is consistent with the DFT studies, where the energetic, electronic, and magnetic properties of the intermediates show a feasible formation of ROS. Present findings are expected to provide new insights into the relationship among the structure, property, and biocidal activity of semiconductor/metal SiO2-Ag composites.

Revealing the Adverse Effects of Trace Amount Broad-Spectrum Antimicrobial: a Direct and Sensitive Visualization Method Based on Carbon Nanoprobe

The widespread use of broad-spectrum antimicrobials has accelerated their entry into aquatic environment, which in turn can adversely affect aquatic organisms and humans, especially in the COVID-19 outbreak and the post-pandemic era. For early detection and intervention of adverse effects, this study develops a new carbon nanoprobe (CNP) that can reveal the adverse effects of trace amount triclosan (TCS), a commonly used broad-spectrum antimicrobial (BSA), through a direct visualization method. CNP has excellent fluorescent properties and strong positive charges, which can be applied as fluorescent indicator and trapped in mitochondria by electrostatic attraction. The highly sensitive responsiveness of CNP to mitochondrial membrane potential ensures the visualization method can be used for monitoring the adverse effects of TCS. The trace amount TCS monitoring is achieved according to the decrease of fluorescence signal in mitochondria and the change of mitochondrial morphological structure from lines to dots. Moreover, monitoring TCS level in aquatic organisms of zebrafish is further realized. Compared with the morphological toxicity test, this visualizing strategy reveals the adverse effects in organisms under low-dose TCS exposure more sensitively. This developed highly sensitive nanoprobe is cruical for direct BSA monitoring and thus prevents the harm of BSA to aquatic organisms and humans.

New Ceramic Multi-Unit Dental Abutments with an Antimicrobial Glassy Coating.

The choice of suitable materials and new designs in oral implantology and the subsequent enhancement of the characteristics of the dental implant developed is an important research topic with wide scope. The present work aims to develop a new multifunctional zirconia-ceria/alumina (Ce-TZP/Al2O3) composite with an antimicrobial glass-based coating to be used in multi-unit abutments compatible with commercially available Ti implants for peri-implantitis prevention. An airbrush spraying technique was effectively applied to coat the sintered ceramic composite starting from a glass powder suspension. This deposition technique was appropriate for obtaining continuous antimicrobial glass-based coatings with homogenous thickness (~35 µm) on ceramic dental implant components. The dental implant systems with the antimicrobial glassy coating were subjected to a mechanical integrity test following ISO 14801 to determine their long-term stability. The tested implant-coating structure seems to be stable under in vitro conditions with ultimate applied forces exceeding the maximum physiological occlusal loading force. This paper also presents a pilot clinical case report that shows peri-implant tissue around the mechanically stable glass coating with no signs of inflammation 1 year after implant insertion. This result is a preliminary probe of the durability and biological tolerance of the glassy material by the gingiva, as well as the antimicrobial effect on the peri-implant microbiota displayed by the coating.

Disinfectants in a "One health" perspective

Disinfectant use is rapidly increasing, due in particular to the Covid-19 pandemic. Its negative consequences, including toxicity, emergence of "tolerant" or resistant bacterial strains and antimicrobial resistance, have now been clearly demonstrated for both human and environmental health. One of the objectives of the European Biocides Directive, which now regulates their marketing authorization, is to encourage reasonable use of disinfectants as part of the "One health" approach. Adequate training is required for prescribers, together with information for consumers and users who also must know when and when not to use them.

Belgian Poison Centre: annual overview 2020

Objective: This study provides an overview of the number and type of calls received by the Belgian Poison Centre (BPC) in 2020. Methods: Data of all calls to the BPC (1 January to 31 December 2020) were collected and analyzed using appropriate statistics (SAS). Results: The BPC received 65,308 calls in 2020 (60,668 in 2019, p<0.05), of which 56,106 (86%) (involving 57,523 victims) were due to an exposure, and 9,202 (14%) were an information request. Despite a minor decrease of 2.3% (21,151 in 2019 versus 20,666 in 2020, p>0.05), the vast majority (35.9%) of exposures were drug-related, of which paracetamol represented 8.2%. Drugs within the category “nervous system” (e.g. antipsychotics, antidepressants, etc.) were most frequently involved (39.6%). There were 11,836 in 2019 versus 12,247 in 2020 (p>0.05). Relating to chemical household products, in the battle against the coronavirus, people bought large quantities and often highly concentrated products, especially products for personal hygiene and cleaning. Poured into smaller containers such as water or soft drink bottles, this led to accidents in which people accidentally drank from the drink container. In an effort to improving cleaning or disinfection, people also started (accidentally) combining or mixing products, with the risk of releasing irritating vapours. Irritation of the mucous membranes and severe shortness of breath were not uncommon. The BPC received 46.1% more calls for bleach and bleach-containing products than in 2019 (835 calls in 2019 compared to 1,220 calls in 2020, p<0.05). A 12.3% increase of cosmetic- and food-related exposures was noted (8,291 in 2019 versus 9,308 in 2020, p<0.05), of which a stable number of exposures (877 in 2019 versus 876 in 2020, p>0.05) were due to essential oils. Exposures to type 1 biocides significantly increased from 322 in 2019 to 1,676 in 2020 (p<0.05), and exposures to type 2 biocides from 406 to 902 (p<0.05). Finally, a 28.2% increase in exposures related to the group “plants, mushrooms and animals” was observed, with 3,256 in 2019 and 4,175 in 2020 (p<0.05). Conclusion: In its history, the BPC has never received as many calls as in 2020, demonstrating its added value in today's and future healthcare. Trends in both, number and type of exposures were impacted by the COVID-19 pandemic.

Impact of COVID-19 on the number and type of calls to the Belgian Poison Centre

Objective: The present study provides an overview of the number and type of calls to the Belgian Poison Centre (BPC), and the impact of COVID-19. Methods: Data of all calls to the BPC (1 January - 31 December 2020) were collected and analysed using appropriate statistics (SAS). Results: The BPC received 65,308 calls in 2020 (60,668 in 2019, p<0.05). The vast majority (35.9%) of exposures were drugrelated (21,151 in 2019 versus 20,666 in 2020, p>0.05), followed by the use of chemical household products (11,836 in 2019 versus 12,247 in 2020 (p>0.05)). A 12.3% increase in the number of cosmetic- and food-related exposures was noted (8,291 in 2019 versus 9,308 in 2020, p<0.05). Within this group, a stable number of exposures (877 in 2019 versus 876 in 2020, p>0.05) due to essential oil exposures were observed. Partly due to the impact of the COVID-19 [1] pandemic, exposures to biocides doubled (104.9%) from 1,964 in 2019 to 4,024 in 2020 (p<0.05). Exposures to type 1 biocides (i.e. human hygiene products, which include alcohol-based hand sanitisers (ABHS)) significantly increased from 322 in 2019 to 1,676 in 2020 (p<0.05), and exposures to type 2 biocides (i.e. disinfectants and algaecides not intended for direct application to humans or animals) from 406 to 902 (p<0.05). In 2020 the BPC received a five-fold increase in the number of calls involving ABHS incidents (both liquid and gel-based, as well as ethanol and isopropanol products) compared to 2019 (1,676 versus 323 in 2019 versus 1,676 in 2020 calls, p<0.05), accounting for 2.6% of all calls in 2020. In 71% of exposures, ingestion was the primary route (1,195/1,676), followed by 28.6% accidental ocular exposures (480/1,676) of which more than half of the incidents involved children (257/480, p<0.05), primarily young children aged 1-4 years (136/257, p<0.05). Finally, as people went into the garden and nature to relax during lockdown, a 28.2% increase in exposures related to the group 'plants, mushrooms and animals' was found, with 3,256 exposures in 2019 and 4,175 in 2020 (p<0.05). Conclusion: In its history, the BPC has never received as many calls as in 2020. The COVID-19 pandemic contributed to a significant number of additional exposures, and requests for toxicologic advice.

Phenotypic Adaptation to Antiseptics and Effects on Biofilm Formation Capacity and Antibiotic Resistance in Clinical Isolates of Early Colonizers in Dental Plaque.

Despite the wide-spread use of antiseptics in dental practice and oral care products, there is little public awareness of potential risks associated with antiseptic resistance and potentially concomitant cross-resistance. Therefore, the aim of this study was to investigate potential phenotypic adaptation in 177 clinical isolates of early colonizers of dental plaque (Streptococcus, Actinomyces, Rothia and Veillonella spp.) upon repeated exposure to subinhibitory concentrations of chlorhexidine digluconate (CHX) or cetylpyridinium chloride (CPC) over 10 passages using a modified microdilution method. Stability of phenotypic adaptation was re-evaluated after culture in antiseptic-free nutrient broth for 24 or 72 h. Strains showing 8-fold minimal inhibitory concentration (MIC)-increase were further examined regarding their biofilm formation capacity, phenotypic antibiotic resistance and presence of antibiotic resistance genes (ARGs). Eight-fold MIC-increases to CHX were detected in four Streptococcus isolates. These strains mostly exhibited significantly increased biofilm formation capacity compared to their respective wild-type strains. Phenotypic antibiotic resistance was detected to tetracycline and erythromycin, consistent with the detected ARGs. In conclusion, this study shows that clinical isolates of early colonizers of dental plaque can phenotypically adapt toward antiseptics such as CHX upon repeated exposure. The underlying mechanisms at genomic and transcriptomic levels need to be investigated in future studies.

New experimental low-cost nanoscience technology for formulation of silver nanoparticles-activated carbon composite as a promising antiviral, biocide, and efficient catalyst

A simple low-cost one-pot photodeposition synthesis with no hazardous reactants or products is used to make silver nanoparticles-activated carbon composite (SNPs@AC). The SNPs are homogenously and photodeposited and absorbed into the activated carbon matrix. Both SNPs and SNPs@AC composite have particle sizes around 10 nm and 100 nm, respectively. The SNPs@AC composite showed good antiviral activity to VERO (ATCC ccl-81) cells. Zeta potential of SNPs@AC composite is −25 mV, showing that this colloidal system is electrically stable and resistant to coagulation. For many Gram-positive and Gram-negative bacteria, the SNPs@AC composite demonstrated strong antibacterial efficacy. The SNPs@AC composite has 75.72 percent anti-inflammatory effect at concentration 500 µg/mL. This composite has a maximum non-toxic concentration (MNTC) of 78.125 g/mL, which corresponds to antiviral activity of up to 96.7 percent against hepatitis A. virus (HAV). It is suggested as a candidate for pharmaceutical formulations, such as integration into the manufacture of N95 masks for COVID-19 infection protection. Concentration 160 μg/mL SNPs@AC composite has antioxidant activity 42.74% percent. The SNPs@AC composite exhibited selective catalytic activity for the organosynthesis hydrazination reaction of 4-chloro-3, 5-di-nitro-benzo-triflouride, giving 1-hydroxy-4-nitro-6-trifluoro-methyl benzotriazole, a common antiviral drug for severe acute respiratory syndrome (SARS). SNPs@composite's well-defined pores provide suitable active sites for binding reactants: 4-Cl-3, 5-di-NO2-benzotriflouride, and hydrazine, which react to create 1-hydroxy-4-nitro-6-trifluoromethyl benzotriazole, which diffuses into solution away from the catalyst surface, leaving the catalyst surface unaffected.

Acinetobacter baumannii: insights towards a comprehensive approach for the prevention of outbreaks in health-care facilities.

Acinetobacter baumannii is known to be an opportunistic pathogen frequently responsible for outbreaks in health-care facilities, particularly in Intensive Care Units (ICU). It can easily survive in the hospital setting for long periods and can be transmitted throughout the hospital in a variety of ways, explored in this review. It can also easily acquire antibiotic resistance determinants rendering several antibiotic drugs useless. In 2019, the US Centre for Disease Control (CDC) considered the organism as an urgent threat. The aim of this review was to raise the awareness of the medical community about the relevance of this pathogen and discuss how it may impact seriously the healthcare institutions particularly in the aftermath of the recent COVID-19 pandemic. PubMed was searched, and articles that met inclusion criteria were reviewed. We conclude by the need to raise awareness to this pathogen's relevance and to encourage the implementation of preventive measures in order to mitigate its consequences namely the triage of specific high-risk patients.

Mechanical Wiping Increases the Efficacy of Liquid Disinfectants on SARS-CoV-2.

High-touch environmental surfaces are acknowledged as potential sources of pathogen transmission, particularly in health care settings where infectious agents may be readily abundant. Methods of disinfecting these surfaces often include direct application of a chemical disinfectant or simply wiping the surface with a disinfectant pre-soaked wipe (DPW). In this study, we examine the ability of four disinfectants, ethanol (EtOH), sodium hypochlorite (NaOCl), chlorine dioxide (ClO2), and potassium monopersulfate (KMPS), to inactivate SARS-CoV-2 on a hard, non-porous surface, assessing the effects of concentration and contact time. The efficacy of DPWs to decontaminate carriers spiked with SARS-CoV-2, as well as the transferability of the virus from used DPWs to clean surfaces, is also assessed. Stainless steel carriers inoculated with approximately 6 logs of SARS-CoV-2 prepared in a soil load were disinfected within 5 min through exposure to 66.5% EtOH, 0.5% NaOCl, and 1% KMPS. The addition of mechanical wiping using DPWs impregnated with these biocides rendered the virus inactive almost immediately, with no viral transfer from the used DPW to adjacent surfaces. Carriers treated with 100 ppm of ClO2 showed a significant amount of viable virus remaining after 10 min of biocide exposure, while the virus was only completely inactivated after 10 min of treatment with 500 ppm of ClO2. Wiping SARS-CoV-2-spiked carriers with DPWs containing either concentration of ClO2 for 5 s left significant amounts of viable virus on the carriers. Furthermore, higher titers of infectious virus retained on the ClO2-infused DPWs were transferred to uninoculated carriers immediately after wiping. Overall, 66.5% EtOH, 0.5% NaOCl, and 1% KMPS appear to be highly effective biocidal agents against SARS-CoV-2, while ClO2 formulations are much less efficacious.

[Effect of virucidal components on highly pathogenic viral agents]. / Actions des composés virucides sur les agents viraux hautement pathogènes.

Highly pathogenic viruses for human, such as Ebolavirus, Lassa virus, variola virus and Coronavirus, can persist several days on inert surfaces. Although their transmission via contaminated surfaces is not clearly demonstrated, it cannot be excluded. Thus, decontamination of these surfaces is necessary to reduce the risk of infection and limit the spread of these viruses. This review summarizes the published data regarding the effectiveness of frequently used virucides on viruses highly pathogenic for human. The data available are rather heterogeneous and therefore difficult to compare. Biocides based on alcohol, aldehyde, iodine, chlorine, peroxide and quaternary ammonium, which are frequently used for directed and zonal decontaminations, are effective. However, their effectiveness depends on many parameters such as formulation of the biocide, the virus concentration, the matrix in which the viral particles are present, the viral strain and the type of contaminated surface. Thus, a biocide should be chosen based on its final use, rather than on its effectiveness compared to other biocides.

Quaternary Ammonium Compounds (QACs) and Ionic Liquids (ILs) as Biocides: From Simple Antiseptics to Tunable Antimicrobials.

Quaternary ammonium compounds (QACs) belong to a well-known class of cationic biocides with a broad spectrum of antimicrobial activity. They are used as essential components in surfactants, personal hygiene products, cosmetics, softeners, dyes, biological dyes, antiseptics, and disinfectants. Simple but varied in their structure, QACs are divided into several subclasses: Mono-, bis-, multi-, and poly-derivatives. Since the beginning of the 20th century, a significant amount of work has been dedicated to the advancement of this class of biocides. Thus, more than 700 articles on QACs were published only in 2020, according to the modern literature. The structural variability and diverse biological activity of ionic liquids (ILs) make them highly prospective for developing new types of biocides. QACs and ILs bear a common key element in the molecular structure-quaternary positively charged nitrogen atoms within a cyclic or acyclic structural framework. The state-of-the-art research level and paramount demand in modern society recall the rapid development of a new generation of tunable antimicrobials. This review focuses on the main QACs exhibiting antimicrobial and antifungal properties, commercial products based on QACs, and the latest discoveries in QACs and ILs connected with biocide development.

[Construction of Continuous Dynamic Model for River Networks and Its Application in Simulation of Spatiotemporal Migration of Typical Biocides].

Biocides are widely added to personal care products and enter the environment through sewage treatment plant (STP) discharge, which affects ecological health. This paper evaluated the pollution characteristics of triclosan and triclocarban in a river network during the COVID-19 epidemic. Moreover, a continuous dynamic river network model coupling a one-dimensional hydrodynamic model and four-level fugacity model was established to address the temporal and spatial heterogeneity of pollutants in the river network migration process; then, this model was applied to evaluate two biocides in the Shima River Basin. The model passed calibration and in-field concentration verification tests and yielded satisfactory simulation results. The results of the study showed that the concentration of biocides in the river network during the new crown epidemic was twice that of the non-epidemic period. The concentration of triclosan and triclocarban in the river channel first increased and then decreased with the increase of the river migration distance after STP discharge. The time variation characteristics of the concentrations were affected by the river flow. The biocide concentration in the river network of the low flow upstream area first increased and then decreased, gradually stabilizing in about 20 h. The pollution concentration in the high flow downstream area was increased, and the concentration did not stabilize at 24 h. These results indicate the necessity of evaluating the temporal and spatial characteristics of migration of typical biocides in the river network by stages and time on the premise of distinguishing the flow.

Biocidal Resistance in Clinically Relevant Microbial Species: A Major Public Health Risk.

Antimicrobial resistance is one of the greatest dangers to public health of the 21st century, threatening the treatment and prevention of infectious diseases globally. Disinfection, the elimination of microbial species via the application of biocidal chemicals, is essential to control infectious diseases and safeguard animal and human health. In an era of antimicrobial resistance and emerging disease, the effective application of biocidal control measures is vital to protect public health. The COVID-19 pandemic is an example of the increasing demand for effective biocidal solutions to reduce and eliminate disease transmission. However, there is increasing recognition into the relationship between biocide use and the proliferation of Antimicrobial Resistance species, particularly multidrug-resistant pathogens. The One Health approach and WHO action plan to combat AMR require active surveillance and monitoring of AMR species; however, biocidal resistance is often overlooked. ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species) pathogens and numerous fungal species have demonstrated drug and biocidal resistance where increased patient mortality is a risk. Currently, there is a lack of information on the impact of biocide application on environmental habitats and ecosystems. Undoubtedly, the excessive application of disinfectants and AMR will merge to result in secondary disasters relating to soil infertility, loss of biodiversity and destruction of ecosystems.