Hand sanitizers: A review of ingredients, mechanisms of action, modes of delivery, and efficacy against coronaviruses

The antimicrobial activity of an antiseptic soap against Candida Albicans and Streptococcus Mutans single and dual-species biofilms on denture base and reline acrylic resins

To evaluate the effect of antiseptic soap on single and dual-species biofilms of Candida albicans and Streptococcus mutans on denture base and reline resins. Samples of the resins were distributed into groups (n = 9) according to the prevention or disinfection protocols. In the prevention protocol, samples were immersed in the solutions (Lifebuoy, 0.5% sodium hypochlorite solution and PBS) for 7, 14 and 28 days before the single and dual-species biofilms formation. Overnight denture disinfection was simulated. In the disinfection protocol, samples were immersed in the same solutions during 8 hours after the single and dual-species biofilms formation. Antimicrobial activity was analyzed by counting colony-forming units (CFU/mL) and evaluating cell metabolism. Cell viability and protein components of the biofilm matrix were evaluated using confocal laser scanning microscopy (CLSM). Data were submitted to ANOVA, followed by Tukey's post-test (α = 0.05) or Dunnett's T3 multiple comparisons test. In the prevention protocol, Lifebuoy solution effectively reduced the number of CFU/mL of both species. In addition, the solution decreased the cell metabolism of the microorganisms. Regarding disinfection protocol, the Lifebuoy solution was able of reduce approximately of 2-3 logs for all the biofilms on the denture base and reline resin. Cellular metabolism was also reduced. The images obtained with CLSM corroborate these results. Lifebuoy solution was effective in reducing single and dual-species biofilms on denture base and reline resins.

Mechanisms of action of microbicides commonly used in infection prevention and control

SUMMARYUnderstanding how commonly used chemical microbicides affect pathogenic microorganisms is important for formulation of microbicides. This review focuses on the mechanism(s) of action of chemical microbicides commonly used in infection prevention and control. Contrary to the typical site-specific mode of action of antibiotics, microbicides often act via multiple targets, causing rapid and irreversible damage to microbes. In the case of viruses, the envelope or protein capsid is usually the primary structural target, resulting in loss of envelope integrity or denaturation of proteins in the capsid, causing loss of the receptor-binding domain for host cell receptors, and/or breakdown of other viral proteins or nucleic acids. However, for certain virucidal microbicides, the nucleic acid may be a significant site of action. The region of primary damage to the protein or nucleic acid is site-specific and may vary with the virus type. Due to their greater complexity and metabolism, bacteria and fungi offer more targets. The rapid and irreversible damage to microbes may result from solubilization of lipid components and denaturation of enzymes involved in the transport of nutrients. Formulation of microbicidal actives that attack multiple sites on microbes, or control of the pH, addition of preservatives or potentiators, and so on, can increase the spectrum of action against pathogens and reduce both the concentrations and times needed to achieve microbicidal activity against the target pathogens.

Hand Sanitizer: Stopping the Spread of Infection at a Cost

The recent rise in hand sanitizer use due to the COVID-19 pandemic has had a beneficial impact on stopping the spread of disease, but the potential negative implications of its overuse on the body and the microbiome have yet to be thoroughly reviewed. Epidermal layers absorb hand sanitizer from direct application to the skin, making them some of the most susceptible cells to the adverse effects of overuse. The increased usage of hand sanitizer can affect the variation, quantity, and diversity of the skin microflora, leading to conditions such as eczema, atopic dermatitis, and even systemic toxicity due to colonization of the skin with pathogenic bacteria. Due to the close-knit relationship between the skin and gut, the gastrointestinal system can also incur disruptions due to the negative effects on the skin as a result of excessive hand sanitizer use, leading to gut dysbiosis. Additionally, the accidental ingestion of hand sanitizer, and its abuse or misuse, can be toxic and lead to alcohol poisoning, which is an issue most commonly seen not only in the pediatric population but also in adolescents and adults due to aberrant recreational exposure. As a vulnerable body system, the eyes can also be negatively impacted by hand sanitizer misuse leading to chemical injury, visual impairment, and even blindness. In this review, we aim to highlight the variations in hand sanitizer formulation, the benefits, and how misuse or overuse may lead to adverse effects on the skin, gut, and eyes. In particular, we review the advantages and disadvantages of alcohol-based hand sanitizers (ABHSs) and non-alcohol-based hand sanitizers (NABHSs) and how the components and chemicals used in each can contribute to organ dysbiosis and systemic damage.

Development and Characterization of a Hand Rub Gel Produced with Artisan Alcohol (Puntas), Silver Nanoparticles, and Saponins from Quinoa

The emergence of the global pandemic (COVID-19) has directed global attention towards the importance of hygiene as the primary defense against various infections. In this sense, one of the frequent recommendations of the World Health Organization (WHO) is regular hand washing and the use of alcohol-based hand sanitizers. Ethanol is the most widely used alcohol due to its effectiveness in eliminating pathogens, ease of use, and widespread production. However, artisanal alcohol, generally used as a spirit drink, could be a viable alternative for developing sanitizing gels. In this study, the use of alcohol "Puntas", silver nanoparticles, and saponins from quinoa was evaluated to produce hand sanitizer gels. The rheological, physicochemical, and antimicrobial properties were evaluated. In the previous assays, the formulations were adjusted to be similar in visual viscosity to the control gel. A clear decrease in the apparent viscosity was observed with increasing shear rate, and an inversely proportional relationship was observed with the amount of ethyl alcohol used in the formulations. The flow behavior index (n) values reflected a pseudoplastic behavior. Oscillatory dynamic tests were performed to analyze the viscoelastic behavior of gels. A decrease in storage modulus (G') and an increase in loss modulus (G″) as a function of the angular velocity (ω) was observed. The evaluation of pH showed that the gels complied with the requirements to be in contact with the skin of the people, and the textural parameters showed that the control gel was the hardest. The use of artisan alcohol could be an excellent alternative to produce sanitizer gel and contribute to the requirements of the population.

Updates and future directions regarding hand hygiene in the healthcare setting: insights from the 3rd ICPIC alcohol-based handrub (ABHR) task force

Healthcare-associated infections (HAIs) and antimicrobial resistance (AMR) pose threats to global health. Effective hand hygiene is essential for preventing HAIs and the spread of AMR in healthcare. We aimed to highlight the recent progress and future directions in hand hygiene and alcohol-based handrub (ABHR) use in the healthcare setting. In September 2023, 42 experts in infection prevention and control (IPC) convened at the 3rd International Conference on Prevention and Infection Control (ICPIC) ABHR Taskforce in Geneva, Switzerland. The purpose of this meeting was to provide a synthesis of recent evidence and formulate a research agenda on four critical areas for the implementation of effective hand hygiene practices: (1) ABHR formulations and hand rubbing techniques, (2) low-resource settings and local production of ABHR, (3) hand hygiene monitoring and technological innovations, and (4) hand hygiene standards and guidelines.

Development of spray-dried powder hand sanitiser with prolonged effectivity

Since the outbreak of the COVID-19 pandemic, the use of hand sanitisers has become an inseparable part of our personal hygiene. However, the short-term effect and the need for frequent application are shortcomings that impair the overall protection. Another aspect is that repeated use of some products (typically alcohol-based) may cause skin irritation or eventually more severe health problems. This work proposes spray-drying as a suitable method for the preparation of swellable chitosan carriers, allowing for encapsulation and sustained release of antibacterial chlorhexidine digluconate as a model active substance. After application to hands, micron-sized particles preferentially accommodate space between epidermal ridges, protected against attrition. Thanks to their small size (d < 10 µm), particles are comfortable to carry since they are not recognisable by somatosensory receptors. The performance of formulations with various amounts of chlorhexidine and cross-linker was tested and compared with selected commercial disinfectants available on the Czech market (ethanol gel and alcoholic solution with chlorhexidine) against E. coli and S. epidermidis. The real-life performance was investigated with twelve volunteers performing various activities for up to 2 h. Finally, a replica of the human index finger with accurately captured micro-topology was proposed and compared with volunteers' fingers concerning the total amount of adhered and detached particles.

Anti-microbial efficacy of a scientifically developed and standardized herbal-alcohol sanitizer

Hands are the primary mode of transmission of microbe-based infections, as they harbor normal microbiota and pathogenic microbes. SARS-CoV-2 has endangered lives worldwide, and WHO has recommended good hygiene practices, especially hand hygiene. In addition, other infectious diseases like diphtheria, measles, tuberculosis, HIV, malaria, etc. are spreading in the shadow of the COVID-19 pandemic. The anti-microbial efficiency of two in-house developed herbal-alcohol based hand sanitizers containing Azadirachta indica, Citrus limon, Zingiber officinale, and Aloe vera (HS1) and Zingiber officinale replaced with Ocimum sanctum (HS2) was evaluated. HS1, with Zingiber officinale, and HS2, with Ocimum sanctum, herbal sanitizers showcased in-vitro anti-viral activity on MDCK cells using the reference strain of influenza A virus, A/PR/8/34 (H1N1), and reduced 99.99% of microbial load within 30 s of contact time, estimated by the Antimicrobial Susceptibility Testing Method. On volunteers, HS1 and HS2 were more effective than alcohol-based WHO sanitizers. Moreover, HS2 sanitizer is more effective against viruses and has better efficiency and hedonic qualities in volunteers than HS1. These sanitizers don't irritate or dry up the skin and have a longer shelf life. Overall, findings reveal that herbal-alcohol-based sanitizers are promising hand hygiene products with the capability of reducing microbial load.

Determination and Quantification of Acetaldehyde, Acetone, and Methanol in Hand Sanitizers Using Headspace GC/MS: Effect of Storage Time and Temperature

Accurate determination of the concentration of alcohols and their metabolites is important in forensics and in several life science areas. A new headspace gas chromatography-mass spectrometry method has been developed to quantify alcohols and their oxidative products using isotope-labeled internal standards. The limit of detection (LOD) of the analytes in the developed method was 0.211 µg/mL for methanol, 0.158 µg/mL for ethanol, 0.157 µg/mL for isopropanol, 0.010 µg/mL for n-propanol, 0.157 µg/mL for acetone, and 0.209 µg/mL for acetaldehyde. The precision and accuracy of the method were evaluated, and the relative standard deviation percentages were found to be less than 3%. This work demonstrates the application of this method, specifically in quantifying the concentration of oxidative products of alcohol and other minor alcohols found in hand sanitizers, which have become an essential household item since the COVID-19 pandemic. Apart from the major components, the minor alcohols found in hand sanitizers include methanol, isopropanol, and n-propanol. The concentration range of these minor alcohols found in ethanol-based hand sanitizer samples was as follows: methanol, 0.000921-0.0151 mg/mL; isopropanol, 0.454-13.8 mg/mL; and n-propanol, 0.00474-0.152 mg/mL. In ethanol-based hand sanitizers, a significant amount of acetaldehyde (0.00623-0.231 mg/mL) was observed as an oxidation product, while in the isopropanol-based hand sanitizer, acetone (0.697 mg/mL) was observed as an oxidation product. The concentration of acetaldehyde in ethanol-based hand sanitizers significantly increased with storage time and temperature, whereas no such increase in acetone concentration was observed in isopropanol-based hand sanitizers with storage time and temperature. In two of the selected hand sanitizers, the acetaldehyde levels increased by almost 200% within a week when stored at room temperature. Additionally, exposing the hand sanitizers to a temperature of 45 °C for 24 h resulted in a 100% increase in acetaldehyde concentration. On the contrary, the acetone level remained constant upon the change in storage time and temperature.

The impact of alcohol hand sanitizer use on skin health between healthcare worker: Cross-sectional study

BACKGROUND

2020 Coronavirus disease 2019 (COVID-19) has become a global health crisis, so hand alcohol-based sanitizers have become essential to preventive measures. Previous studies reported that hand sanitizers could kill bacteria and viruses; however, using them excessively can lead to health problems if misused. In light of sanitizer overuse, the availability of various products and qualities in the market, and the absence of data on skin problems, we conducted a survey study about the impact of commonly used sanitizers on skin health, particularly on hands. The study aimed to determine the prevalence and the correlation between hand sanitizer and skin health during the COVID-19 pandemic at the National Guard Institute- Jeddah, Saudi Arabia.

METHODS

A cross-sectional study was conducted using a self-administered online questionnaire by sending an invitation link to students and employees of the National Guard Institute- Jeddah, Saudi Arabia, in 2021. A chi-squared test was used to obtain differences concerning awareness of hand sanitizer use/type and hand skin health.

RESULTS

In the total 216 participants, there were considerably more skin conditions reported by women (62.5%) and respondents ages 31-40 (36.6%). For the types of hand sanitizers, 89.8%, 40.9%, 30.2%, 4.7%, and 6% were recorded: gel, spray, wipes, foam, and others, respectively, and the survey applicants were filled by 60.6% of non-medical workers. According to the survey, 32.9% of participants experienced a hand crack, which was the most common hand side effect. The handwashing frequency was reported between 3 to 7 times per day during the COVID-19 pandemic, and 9.3% of participants used hand sanitizers more than 10 times daily.

CONCLUSION

It was found that during the pandemic, skin changes were common among the NGHA population and healthcare workers. Consequently, the adverse health effects of these hand sanitizers on human health may result in multiple infections and toxicity. The present study provides appropriate knowledge on the types and ingredients of hand sanitizers as essential factors for skin health, preventing health risks during this pandemic.

Development and Evaluation of an Eco-Friendly Hand Sanitizer Formulation Valorized from Fruit Peels

Hand sanitizer usage has proven to be a common and practical method for reducing the spread of infectious diseases which can be caused by many harmful pathogens. There is a need for alcohol-free hand sanitizers because most hand sanitizers on the market are alcohol-based, and regular use of them can damage the skin and can be hazardous. India is the world's largest producer of fruits and one of the major problems after fruit consumption is their peels, causing waste management problems and contributing to the formation of greenhouse gases leading to air pollution and adding to the problem of climate change. Valorization of such wastes into other value-added products and their incorporation into formulations of eco-friendly alcohol-free hand sanitizers would solve these issues, save the environment, benefit the society, and help in achieving the sustainable development goals. Thus, this research focuses on formulating an effective natural alcohol-free hand sanitizer that harnesses the antimicrobial properties of the various types of bioactive components found in fruit peels of pomegranate, sweet lime, and lemon. The peel extracts and the formulated sanitizer proved considerable antimicrobial activity against the pathogenic Escherichia coli and hand microflora. Molecular docking was also applied to examine ligand-protein interaction patterns and predict binding conformers and affinity of the sanitizer phytocompounds towards target proteins in COVID-19, influenza, and pneumonia viruses. The binding affinities and the protein-ligand interactions virtual studies revealed that the sanitizer phytocompounds bind with the amino acids in the target proteins' active sites via hydrogen bonding interactions. As a result, it is possible to formulate a natural, alcohol-free hand sanitizer from fruit peels that is effective against pathogenic germs and viruses using the basic structure of these potential findings.

Looking beyond vaccines: Cultural tightness-looseness moderates the relationship between immunization coverage and disease prevention vigilance

Advancements in vaccination technologies mitigate disease transmission risks but may inadvertently suppress the behavioral immune system, an evolved disease avoidance mechanism. Applying behavioral immune system theory and utilizing robust big data analytics, we examined associations between rising vaccination coverage and government policies, public mobility, and online information seeking regarding disease precautions. We tested whether cultural tightness-looseness moderates the relationship between mass immunization and disease prevention vigilance. Comprehensive time series analyses were conducted using American data (Study 1) and international data (Study 2), employing transfer function modeling, cross-correlation function analysis, and meta-regression analysis. Across both the US and global analyses, as vaccination rates rose over time, government COVID-19 restrictions significantly relaxed, community mobility increased, and online searches for prevention information declined. The relationship between higher vaccination rates and lower disease prevention vigilance was stronger in culturally looser contexts. Results provide initial evidence that mass immunization may be associated with attenuated sensitivity and enhanced flexibility of disease avoidance psychology and actions. However, cultural tightness-looseness significantly moderates this relationship, with tighter cultures displaying sustained vigilance amidst immunization upticks. These findings offer valuable perspectives to inform nuanced policymaking and public health strategies that balance prudent precautions against undue alarm when expanding vaccine coverage worldwide.

Assessment of quality of commercial hand sanitizers using Fourier transform infrared spectroscopy and gas chromatography

Since the beginning of the COVID-19 pandemic, the use and manufacture of alcohol-based hand sanitizers increased exponentially. Efficacy of hand sanitizers mainly depends on active ingredients like ethanol and isopropanol (IPA). Even though methanol is extremely hazardous to people, it is still illegally used in hand sanitizers in Bangladesh. Developing a quick and simple analytical method for detecting and quantifying ethanol/IPA/methanol is crucial. Here, Fourier transform infrared spectroscopy (FTIR) was used to identify and quantify alcohol content in commercially available hand sanitizers in a quick and easy way. Comparing the FTIR and GC data, provided quite similar results. Unlike previous studies by FTIR, C-H, CH₃-C-CH₃ stretching, and C-H bending vibrational modes were employed to construct analytical calibration curves to detect and quantify alcohol in hand sanitizers. According to FTIR and GC findings, ethanol and IPA content were found to be 43-82% and 40-69%, and 56-64% and 61-66%, respectively, whereas ethanol was labeled at 66-80% and IPA at 65-70%. FTIR and GC revealed methanol content ranging from 37 to 98 and 19 to 81%, respectively. Also, the FTIR was significantly faster than the GC. Therefore, FTIR can be used to commercially analyze the quality of hand sanitizers.•FTIR was used to identify and quantify alcohol content in commercially available hand sanitizers in a quick and easy way.•Comparing the FTIR and GC data, provided quite similar results.•Out of ten samples, five contained ethanol, three IPA, and two methanol.

Environmental dissemination of respiratory viruses: dynamic interdependencies of respiratory droplets, aerosols, aerial particulates, environmental surfaces, and contribution of viral re-aerosolization

During the recent pandemic of COVID-19 (SARS-CoV-2), influential public health agencies such as the World Health Organization (WHO) and the U.S. Centers for Disease Control and Prevention (CDC) have favored the view that SARS CoV-2 spreads predominantly via droplets. Many experts in aerobiology have openly opposed that stance, forcing a vigorous debate on the topic. In this review, we discuss the various proposed modes of viral transmission, stressing the interdependencies between droplet, aerosol, and fomite spread. Relative humidity and temperature prevailing determine the rates at which respiratory aerosols and droplets emitted from an expiratory event (sneezing, coughing, etc.) evaporate to form smaller droplets or aerosols, or experience hygroscopic growth. Gravitational settling of droplets may result in contamination of environmental surfaces (fomites). Depending upon human, animal and mechanical activities in the occupied space indoors, viruses deposited on environmental surfaces may be re-aerosolized (re-suspended) to contribute to aerosols, and can be conveyed on aerial particulate matter such as dust and allergens. The transmission of respiratory viruses may then best be viewed as resulting from dynamic virus spread from infected individuals to susceptible individuals by various physical states of active respiratory emissions, instead of the current paradigm that emphasizes separate dissemination by respiratory droplets, aerosols or by contaminated fomites. To achieve the optimum outcome in terms of risk mitigation and infection prevention and control (IPAC) during seasonal infection peaks, outbreaks, and pandemics, this holistic view emphasizes the importance of dealing with all interdependent transmission modalities, rather than focusing on one modality.

Factors associated with better alcohol hand rub in 2020. Results from the French national audit "Pulpe'friction"

Background

The application of alcohol-based hand rub on hands (ABHR) can prevent the transmission of microorganisms. But, in some situations the practices remain perfectible.

Aim

The aim of this study was to assess the self-reported ABHR practices of healthcare workers (HCWs) and to identify the factors associated with better ABHR compliance.

Methods

A cross-sectional study was conducted using the French national "Pulpe'friction" audit, from 1st January 2020 to 31st December 2020, in healthcare facilities and social welfare facilities in France. Data were analyzed using descriptive statistics and multivariate logistic regression models.

Results

Of the 6769 HCWs, the average ABHR compliance was 75% "before patient contact," 95% "before an invasive technique," 86% "after patient contact," and 79% "after contact with patient surroundings." The main reported barriers were the availability, the discomfort and the harmfulness of the product. The factors significantly associated with a better compliance were the individual importance given to hand hygiene (HH); working in a healthcare facility, except in the situation "before an invasive technique"; medical profession "after patient contact"; paramedical profession "after contact with patient surroundings."

Discussion

These results call for national actions to fight the most reported barriers and raise awareness on the importance of HH, especially before touching the patient.

Adult and children's use of hand sanitizer during a pandemic - an observational study

BACKGROUND

The use of hand sanitizers has been one of the key public health measures recommended to reduce the transmission of SARS-CoV-2 during the pandemic. As such, its daily use among the general population has reportedly increased dramatically since the onset of the COVID-19 pandemic.

OBJECTIVE

To better understand the impact of this recommendation, hand sanitizer use, including the frequency and amount handled, was examined among adults in a non-occupational setting and children in both the home and school/childcare settings.

METHODS

An online survey of Canadians (conducted from September to October 2021) was employed to estimate use frequency, amount, and pattern of hand sanitizer use.

RESULTS

Responses were received from 655 adults in the general population and 298 teachers of children up to the age of 18 years. The frequency of hand sanitizer use during the pandemic was found to be as high as 25 times per day in children and over 9 times per day in adults. Notable differences were found when comparing the frequency of hand sanitizer use by children in the home to children in a school or childcare setting.

SIGNIFICANCE

This is the first study, known to the authors, examining hand sanitizer use among children during the pandemic, including use in a childcare or school setting. This study illustrates the importance of examining the change in consumer behaviors during a pandemic and the need to look beyond the home when attempting to understand product use patterns in children.

IMPACT STATEMENT

This research explores uses of hand sanitizer, before and during pandemic conditions, in the general population of Canada with a particular focus on use among children. The results can be used to estimate exposure to chemicals in hand sanitizer from non-occupational use in Canada and among similar populations and signal the importance of examining changing consumer behaviors and use of consumer products in school settings, especially among children.

Hand Sanitizer Gels: Classification, Challenges, and the Future of Multipurpose Hand Hygiene Products

Hand hygiene is a crucial measure in the prevention and control of infections, and there is a growing awareness among individuals who are making a conscious effort to maintain hand cleanliness. With the advent of the SARS-CoV-2 outbreak, the demand for hand hygiene products has also gradually shifted towards those with antimicrobial properties. Among these products, hand sanitizer gels (HSGs) have gained considerable popularity as an efficient method of hand cleaning, due to their rapid drying and sustained antimicrobial efficacy. Concurrently, there has been a growing interest in novel HSGs that offer additional functions such as skin whitening, moisturizing, and anti-inflammatory effects. These novel HSGs effectively address concerns associated with the ingestion of antimicrobial ingredients and demonstrate reduced skin irritation, thereby alleviating hand dermatological issues. This review provides an extensive overview of the application scenarios, classification, and challenges associated with HSGs while emphasizing the emergence of novel components with biological functions, aiming to contribute to the advancement of hand hygiene practices and offer novel insights for the development of novel HSGs with outstanding antimicrobial properties with other multiple biological functions and desirable biosafety profiles.

Comparative evaluation of the effectiveness of alcohol-based sanitizers, UV-C radiation and hot air on three-age Salmonella biofilms

Dry sanitation is recommended to control contamination and prevent microbial growth and biofilm formation in the low-moisture food manufacturing plants. The objective of this study was to evaluate the effectiveness of dry sanitation protocols on Salmonella three-age biofilms formed on stainless steel (SS) and polypropylene (PP). Biofilms were formed for 24, 48 and 96 h at 37 °C using a cocktail of six Salmonella strains (Muenster, Miami, Glostrup, Javiana, Oranienburg, Yoruba) isolated from the peanut supply chain. Then, the surfaces were exposed to UV-C radiation, hot air (90 °C), 70% ethanol and a commercial product based on isopropyl alcohol for 5, 10, 15 and 30 min. After 30min exposure, on PP the reductions ranged from 3.2 to 4.2 log CFU/cm² for UV-C, from 2.6 to 3.0 log CFU/cm² for hot air, from 1.6 to 3.2 log CFU/cm² for 70% ethanol and from 1.5 to 1.9 log CFU/cm² for the commercial product. On SS, after the same exposure time, reductions of 1.3-2.2 log CFU/cm², 2.2 to 3.3 log CFU/cm², 1.7 to 2.0 log CFU/cm² and 1.6 to 2.4 log CFU/cm² were observed for UV-C, hot air, 70% ethanol and commercial product, respectively. UV-C was the only treatment affected by the surface material (p < 0.05) whereas the biofilm age influenced the effectiveness of UV-C and hot air (p < 0.05). For most treatment, there was significant difference among the exposure times (p < 0.05). Overall, the fastest loss in the biofilm viability was noted in the first 5 min, followed by a tail phase. The time predicted by the Weibull model for the first decimal reduction ranged from 0.04 to 9.9 min on PP and from 0.7 to 8.5 min on SS. In addition, the Weibull model indicates that most of treatments (79%) required a long-term exposure time (>30 min) to achieve 3-log reductions of Salmonella biofilms. In summary, UV-C showed the best performance on PP whereas hot air was noted to be the most effective on SS.

Investigating and combatting the key drivers of viral zoonoses in Africa: an analysis of eight epidemics

Investigating the interplay of factors that result in a viral zoonotic outbreak is difficult, though it is increasingly important. As anthropogenic influences shift the delicate balance of ecosystems, new zoonoses emerge in humans. Sub-Saharan Africa is a notable hotspot for zoonotic disease due to abundant competent mammalian reservoir hosts. Furthermore, poverty, corruption, and an overreliance on natural resources play considerable roles in depleting biological resources, exacerbating the population's susceptibility. Unsurprisingly, viral zoonoses have emerged in Africa, including HIV/AIDS, Ebola, Avian influenza, Lassa fever, Zika, and Monkeypox. These diseases are among the principal causes of death in endemic areas. Though typically distinct in their manifestations, viral zoonoses are connected by underlying, definitive factors. This review summarises vital findings on viral zoonoses in Africa using nine notable case studies as a benchmark for future studies. We discuss the importance of ecological recuperation and protection as a central strategy to control zoonotic diseases. Emphasis was made on moderating key drivers of zoonotic diseases to forestall future pandemics. This is in conjunction with attempts to redirect efforts from reactive to pre-emptive through a multidisciplinary "one health" approach.

Inactivation kinetics of benzalkonium chloride and ethanol-based hand sanitizers against a betacoronavirus and an alphacoronavirus

Background

Hand hygiene is critical to lower the potential for the spread of SARS-CoV-2 and other infectious agents by direct contact. When running water and soap are not available for hand hygiene, ethanol-based hand sanitizers are currently the recommended standard of care [[1], [2], [3]]. Though recently published data showed comparable in vitro effectiveness of benzalkonium chloride (BAK)-based and ethanol-based hand sanitizers against SARS-CoV-2 virus, a paucity of peer-reviewed data on the effectiveness of these formulations against other types of infective coronaviruses remains. This work assessed human coronavirus HCoV-229E (genus Alphacoronavirus) concurrently with SARS-CoV-2, Isolate USA-WA1/2020 (genus Betacoronavirus) to fill this gap.

Methods

The test was conducted according to EN14476:2013-A2:2019 [EN14476] Quantitative Suspension Test for the Evaluation of Virucidal Activity in the Medical Area [4]. Two BAK-based hand sanitizers, five ethanol-based hand sanitizers, and an 80% ethanol reference formulation were tested for antiviral activity against SARS-CoV-2 and HCoV-229E at 15- and 30- second contact times.

Results

Both SARS-CoV-2 and HCoV-229E were reduced by greater than 4.00-log₁₀ within 15 seconds of contact. Virus decay constants (k) following first-order kinetics were similar for BAK and ethanol-based formulations against both test viruses. The SARS-CoV-2 results reported herein mirrored previous data reported by Herdt et al. (2021).

Conclusion

BAK and ethanol hand sanitizer formulations inactivate SARS-CoV-2 and HCoV-229E at similar rates. This data supports previously published effectiveness data for both chemistries and indicates that additional coronavirus strains and variants would demonstrate similar inactivation trends.

Synthesis of Chitosan-Silver Nanocomposite and Its Evaluation as an Antibacterial Coating for Mobile Phone Glass Protectors

An easy and environment-friendly route for antibacterial coating suited for mobile phone glass protectors was successfully demonstrated. In this route, freshly prepared chitosan solution in 1% v/v acetic acid was added with 0.1 M silver nitrate solution and 0.1 M sodium hydroxide solution and incubated with agitation at 70 °C to form chitosan-silver nanoparticles (ChAgNPs). Varied concentrations of chitosan solution (i.e., 0.1, 0.2, 0.4, 0.6, and 0.8% w/v) were used to investigate its particle size, size distribution, and later on, its antibacterial activity. Transmission electron microscope (TEM) imaging revealed that the smallest average diameter of silver nanoparticles (AgNPs) was 13.04 nm from 0.8% w/v chitosan solution. Further characterizations of the optimal nanocomposite formulation using UV-vis spectroscopy and Fourier transfer infrared spectroscopy were also performed. Using a dynamic light scattering zetasizer, the average ζ-potential of the optimal ChAgNP formulation was at +56.07 mV, showing high aggregative stability and an average ChAgNP size of 182.37 nm. The ChAgNP nanocoating on glass protectors shows antibacterial activity against Escherichia coli (E. coli) at 24 and 48 h of contact. However, the antibacterial activity decreased from 49.80% (24 h) to 32.60% (48 h).

Comparative Virucidal Activities of Essential Oils and Alcohol-Based Solutions against Enveloped Virus Surrogates: In Vitro and In Silico Analyses

The large-scale use of alcohol (OH)-based disinfectants to control pathogenic viruses is of great concern because of their side effects on humans and harmful impact on the environment. There is an urgent need to develop safe and environmentally friendly disinfectants. Essential oils (EOs) are generally recognized as safe (GRAS) by the FDA, and many exhibit strong antiviral efficacy against pathogenic human enveloped viruses. The present study investigated the virucidal disinfectant activity of solutions containing EO and OH against DENV-2 and CHIKV, which were used as surrogate viruses for human pathogenic enveloped viruses. The quantitative suspension test was used. A solution containing 12% EO + 10% OH reduced > 4.0 log10 TCID₅₀ (100% reduction) of both viruses within 1 min of exposure. In addition, solutions containing 12% EO and 3% EO without OH reduced > 4.0 log10 TCID₅₀ of both viruses after 10 min and 30 min of exposure, respectively. The binding affinities of 42 EO compounds and viral envelope proteins were investigated through docking analyses. Sesquiterpene showed the highest binding affinities (from -6.7 to -8.0 kcal/mol) with DENV-2 E and CHIKV E1-E2-E3 proteins. The data provide a first step toward defining the potential of EOs as disinfectants.

Infection prevention and control: a guide for community nurses

The onset of the COVID-19 pandemic highlighted the importance of infection prevention and control (IPC), and accentuated the need for better health and safety measures to protect both healthcare professionals and their patients. In this article, Francesca Ramadan provides an overview of IPC measures for community nurses, such as hand hygiene and personal protective equipment, along with the safe management of care equipment and the care environment.

Association between COVID-19 infection rates by region and implementation of non-pharmaceutical interventions: a cross-sectional study in Japan

BACKGROUND

During a pandemic, non-pharmaceutical interventions (NPIs) play an important role in protecting oneself and others from infection. There are large regional differences in COVID-19 infection rates in Japan. We hypothesized that the local infection incidence may affect adherence to individual NPIs.

METHODS

This cross-sectional study was conducted online among full-time workers in Japan in December 2020. The questionnaire asked the respondents to identify their habits regarding seven common NPIs (wearing masks, washing hands after the bathroom, disinfecting hands when entering indoors, gargling when returning home, ventilating the room, disinfecting or washing hands after touching frequently touched surfaces, carrying alcohol sanitizers when outdoors).

RESULTS

A total of 27 036 participants were analyzed. Compared with the region with the lowest infection rate, five of the seven NPIs showed statistically significant trends across regional infection levels, the two exceptions being wearing masks and washing hands after the bathroom. Multivariate adjustment did not change these trends.

CONCLUSIONS

This study found that NPIs were more prevalent in regions with higher incidence rates of COVID-19 in Japanese workers. The findings suggest that the implementation of NPIs was influenced not only by personal attributes but also by contextual effects of the local infection level.

Infection Control in Dental Practice during the COVID-19 Pandemic: What Is Changed?

The COVID-19 pandemic has profoundly changed our lives. Since the SARS-CoV-2 was discovered, many studies have been done on the transmission mode, its replication within humans, and its survival even in the outside environment and on inanimate surfaces. Undoubtedly, health care workers have faced the greatest risks because of their close contact with potentially infected patients. Of these, dental health care professionals are certainly among the most vulnerable categories, precisely because infection occurs with the airborne virus. The treatment of patients within the dental office has changed profoundly, respecting all preventive measures towards the patient and the practitioners themselves. The aim of this paper is to understand whether the protocols changed for the prevention of SARS-CoV-2 infection among dentists remained even after the most acute phase of the pandemic. In particular, this study analyzed habits, protocols, preventive measures, and any costs incurred in the COVID-19 era for the prevention of SARS-CoV-2 infection among dental workers and patients.

Adsorption and Inactivation of SARS-CoV-2 on the Surface of Anatase TiO2(101)

We investigated the adsorption of severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), the virus responsible for the current pandemic, on the surface of the model catalyst TiO₂(101) using atomic force microscopy, transmission electron microscopy, fluorescence microscopy, and X-ray photoelectron spectroscopy, accompanied by density functional theory calculations. Three different methods were employed to inactivate the virus after it was loaded on the surface of TiO₂(101): (i) ethanol, (ii) thermal, and (iii) UV treatments. Microscopic studies demonstrate that the denatured spike proteins and other proteins in the virus structure readsorb on the surface of TiO₂ under thermal and UV treatments. The interaction of the virus with the surface of TiO₂ was different for the thermally and UV treated samples compared to the sample inactivated via ethanol treatment. AFM and TEM results on the UV-treated sample suggested that the adsorbed viral particles undergo damage and photocatalytic oxidation at the surface of TiO₂(101) which can affect the structural proteins of SARS-CoV-2 and denature the spike proteins in 30 min. The role of Pd nanoparticles (NPs) was investigated in the interaction between SARS-CoV-2 and TiO₂(101). The presence of Pd NPs enhanced the adsorption of the virus due to the possible interaction of the spike protein with the NPs. This study is the first investigation of the interaction of SARS-CoV-2 with the surface of single crystalline TiO₂(101) as a potential candidate for virus deactivation applications. Clarification of the interaction of the virus with the surface of semiconductor oxides will aid in obtaining a deeper understanding of the chemical processes involved in photoinactivation of microorganisms, which is important for the design of effective photocatalysts for air purification and self-cleaning materials.

Pollution free UV-C radiation to mitigate COVID-19 transmission

The high rate of transmission of the COVID-19 virus has brought various types of disinfection techniques, for instance, hydrogen peroxide vaporization, microwave generating steam, UV radiation, and dry heating, etc. to prevent the further transmission of the virus. The chemical-based techniques are predominantly used for sanitization of hands, buildings, hospitals, etc. However, these chemicals may affect the health of humans and the environment in unexplored aspects. Furthermore, the UV lamp-based radiation sanitization technique had been applied but has not gained larger acceptability owing to its limitation to penetrate different materials. Therefore, the optical properties of materials are especially important for the utilization of UV light on such disinfection applications. The germicidal or microorganism inactivation application of UV-C has only been in-use in a closed chamber, due to its harmful effect on human skin and the eye. However, it is essential to optimize UV for its use in an open environment for a larger benefit to mitigate the virus spread. In view of this, far UV-C (222 nm) based technology has emerged as a potential option for the sanitization in open areas and degradation of microorganisms present in aerosol during the working conditions. Hence, in the present review article, efforts have been made to evaluate the technical aspects of UV (under the different spectrum and wavelength ranges) and the control of COVID 19 virus spread in the atmosphere including the possibilities of the human body sanitization in working condition.

Visibility and Accessibility of Hand Hygiene Stations and Fatigue Among Nurses Working in Long-Term Care (LTC) During the COVID-19 Pandemic

OBJECTIVES

Evaluate the relationship between nurses' perception of the long-term care (LTC) environment, specifically having visible and accessible hand hygiene stations (HHS), and nurses' fatigue during the COVID-19 pandemic.

BACKGROUND

LTC nurses experience not only heavy workloads and fatigue but also a high risk of infection during the COVID-19 pandemic. Few studies have evaluated the relationship between safety measures such as having visible and accessible HHS and nurses' fatigue.

METHODS

The cross-sectional COVID-19 Impact on Nurses Study (COINS) was an online survey distributed to members of the American Association of Post-Acute Care Nursing through the REDCap survey platform, between June 1, 2020, and January 31, 2021. Logistic regression modeling was conducted to identify the relationship between nurses' perception of having visible and accessible HHS and fatigue among LTC nurses.

RESULTS

The majority of LTC nurse respondents (78.35%) reported having moderate to very severe fatigue. Nurses who reported not having enough visible and accessible HHS in their work environment have statistically significantly higher odds (odds ratio [OR] = 0.37, 95% confidence interval [CI] [0.20, 0.70], p = .002) of reporting experiencing moderate to very severe fatigue compared to nurses who perceived there was adequate HHS. The logistic regression is significant while controlling for sociodemographic differences, guilt for family and patients, support from work, and confidence in the future of LTC.

CONCLUSIONS

This study reveals the LTC environment that incorporates better considerations of more visible and accessible HHS might mitigate nurses' fatigue during the pandemic. A conceptual framework has been proposed for future studies.

Dry surface biofilms in the food processing industry: An overview on surface characteristics, adhesion and biofilm formation, detection of biofilms, and dry sanitization methods

Bacterial biofilm formation in low moisture food processing (LMF) plants is related to matters of food safety, production efficiency, economic loss, and reduced consumer trust. Dry surfaces may appear dry to the naked eye, however, it is common to find a coverage of thin liquid films and microdroplets, known as microscopic surface wetness (MSW). The MSW may favor dry surface biofilm (DSB) formation. DSB formation is similar in other industries, it occurs through the processes of adhesion, production of extracellular polymeric substances, development of microcolonies and maturation, it is mediated by a quorum sensing (QS) system and is followed by dispersal, leading to disaggregation. Species that survive on dry surfaces develop tolerance to different stresses. DSB are recalcitrant and contribute to higher resistance to sanitation, becoming potential sources of contamination, related to the spoilage of processed products and foodborne disease outbreaks. In LMF industries, sanitization is performed using physical methods without the presence of water. Although alternative dry sanitizing methods can be efficiently used, additional studies are still required to develop and assess the effect of emerging technologies, and to propose possible combinations with traditional methods to enhance their effects on the sanitization process. Overall, more information about the different technologies can help to find the most appropriate method/s, contributing to the development of new sanitization protocols. Thus, this review aimed to identify the main characteristics and challenges of biofilm management in low moisture food industries, and summarizes the mechanisms of action of different dry sanitizing methods (alcohol, hot air, UV-C light, pulsed light, gaseous ozone, and cold plasma) and their effects on microbial metabolism.

Development and Evaluation of BLE-Based Room-Level Localization to Improve Hand Hygiene Performance Estimation

Hand hygiene is one of the most effective ways to prevent infection transmission. However, current electronic monitoring systems are not able to identify adherence to all hand hygiene (HH) guidelines. Location information can play a major role in enhancing HH monitoring resolution. This paper proposes a BLE-based solution to localize healthcare workers inside the patient room. Localization accuracy was evaluated using one to four beacons in a binary (entrance/proximal patient zone) or multiclass (entrance/sink/right side of the bed/left side of the bed) proximity-based positioning problem. Dynamic fingerprints were collected from nine different subjects performing 30 common nursing activities. Extremely randomized trees algorithm achieved the best accuracies of 81% and 71% in the binary and multiclass classifications, respectively. The proposed method can be further used as a proxy for caregiving activity recognition to improve the risk of infection transmission in healthcare settings.

The Assessment of Skin Homeostasis Changes after Using Different Types of Excipients in Healthy Individuals

Excipients are used as vehicles for topical treatments; however, there are not many studies that evaluate the impact of different excipients themselves. The aim of this research is to assess skin homeostasis changes in healthy individuals after using water/oil (W/O), oil/water (O/W), Beeler base, foam and Vaseline excipients. A within-person randomized trial was conducted that included healthy individuals without previous skin diseases. Skin barrier function parameters, including stratum corneum hydration (SCH), transepidermal water loss (TEWL), pH, temperature, erythema, melanin and elasticity (R0, R2, R5 and R7), were measured on the volar forearm before and after using each excipient. Sixty participants were included in the study, with a mean age of 32 years. After applying w/o excipient erythema decreased by 25 AU, (p < 0.001) and elasticity increased by 6%. After using the o/w excipient, erythema decreased by 39.36 AU (p < 0.001) and SCH increased by 6.85 AU (p = 0.009). When applying the Beeler excipient, erythema decreased by 41.23 AU (p < 0.001) and SCH increased by 15.92 AU (p < 0.001). Foam and Vaseline decreased TEWL and erythema. Excipients have a different impact on skin barrier function. Knowing the effect of excipients on the skin could help to develop new topical treatments and help specialists to choose the best excipient according to the pathology.

Hand Sanitizer Gel Formulation with Laccase Enzyme as an Antibacterial Against Staphylococcus aureus and Escherichia coli

Laccase enzymes have been used widely in industrial fields such as textile, pulp, paper, food, cosmetic, and pharmaceutical industries. Laccase is used in toothpaste, mouthwash, deodorants, and soaps in personal care products. Previously, laccase enzymes had never been used for formulating hand sanitizer gel. This study aimed to determine the effect of the laccase enzyme on the physicochemical properties and the antibacterial potential of the hand sanitizer gel against pathogenic bacteria. Laccase enzyme was produced through fermentation using the fungus Trametes hirsuta EDN 082 with an activity of 0.032 U/mL. Hand sanitizer gel was made with the addition of laccase enzyme with varying concentrations of 4, 7, and 10% (v/v). The physicochemical test included organoleptic tests, pH evaluation, gel spreadability, and viscosity. The antibacterial was tested by the palm swab method. The gel physicochemical characteristics showed that the more laccase enzyme added, the more yellow the color produced, the less thick the shape, the wider the gel spreadability, and the lower the viscosity. The obtained pH ranged from 7.4 to 7.6. The best formulation of the hand sanitizer gel was achieved with the addition of a 7% (v/v) laccase enzyme. This formulation can reduce the number of bacteria colonies of Staphylococcus aureus and Escherichia coli on the palms with effectiveness above 95%. The laccase enzyme can be used as an active ingredient and antibacterial agent in the formulation of hand sanitizers.

An Overview of Repurposed Drugs for Potential COVID-19 Treatment

The COVID-19 pandemic caused by SARS-CoV-2 has placed severe constraints on healthcare systems around the globe. The SARS-CoV-2 virus has caused upheaval in the healthcare and economic sectors worldwide. On the 20th of May 2020, the World Health Organisation declared COVID-19 a global pandemic due to the unprecedented number of cases reported around the globe. As of the 4th of November 2022, there were 637,117,429 coronavirus cases reported globally by Worldometer stats, with 6,602,572 related deaths. In South Africa, there were approximately 4,029,496 coronavirus cases and 102,311 associated deaths. As such, there is a need for efficacious therapeutic regimes. There has been a paucity of knowledge encompassing the use of effective and specific antiviral drug therapies for treating COVID-19 since the outbreak. In this review, we provide valuable insights into the repurposing of current drugs for COVID-19. Drug repurposing provides a suitable option for the discovery of efficacious drugs for COVID-19, thereby decreasing the costs and turnaround times of drug development strategies. This review provides an overview of ten drugs, including antimalarial, antiparasitic, anti-inflammatory, nucleoside analogue, monoclonal-antibody drugs, that were repurposed for the potential treatment of COVID-19.

A Long-Lasting Skin Protectant Based on CG-101, a Deep Eutectic Solvent Comprising Choline and Geranic Acid

The COVID-19 public health crisis has spotlighted the need to improve global hygiene and sanitization. In addition to causing staggering rates of transmission and fatality, COVID-19 has severely impacted the quality of life and mental health of global citizens. The World Health Organization (WHO) and Centers for Disease Control and Prevention (CDC) encourage hand hygiene as the first defense against the spread of infection, yet frequent handwashing is often impractical. Widely used ethanol-based hand sanitizers provide immediate protection against pathogens on the skin, albeit short-lived, due to their rapid evaporation. Herein, a novel, long-lasting skin protectant formulated with biocompatible ionic liquid/deep eutectic solvents prepared using generally recognized as safe materials - choline and geranic acid (CG-101, 5% w/w) - is described. In vitro studies demonstrated that CG-101 inactivates bacteria and the human coronavirus, hCoV229E, for 4 h after application. Two human clinical studies demonstrate that CG-101 does not cause skin irritation or sensitization, and a single application of CG-101 gel imparts skin protection against microbes for significantly longer than conventional 70% ethanol-based hand sanitizers. These data are the first to indicate that CG-101 may be a better alternative to alcohol-based hand sanitizers for long-term skin protection against infectious diseases.

Impact of COVID-19 on viral respiratory infection epidemiology in young children: A single-center analysis

Background

The COVID-19 pandemic impacts different health aspects. Concomitant with the adoption of non-pharmaceutical interventions (NPIs) to reduce the spread of SARS-CoV-2, global surveillance studies reported a reduction in occurrence of respiratory pathogens like influenza A and B virus (IAV & IBV) and respiratory syncytial virus (RSV). We hypothesized to observe this collateral benefit on viral respiratory infection epidemiology in young children.

Methods

Respiratory samples of children aged below 6 years, presenting at the outpatient clinic, emergency department, or pediatric infectious diseases department of the University Hospitals Leuven, between April 2017 and April 2021 were retrospectively analyzed. The occurrence (positivity rate), and seasonal patterns of viral respiratory infections were described. Chi-squared or Fisher's exact test (and Bonferroni correction) were used to explore differences in occurrence between 2020-2021 and previous 12-month (April to April) periods.

Results

We included 3020 samples (453 respiratory panels, 2567 single SARS-CoV-2 PCR tests). IAV and IBV were not detected from March and January 2020, respectively. For IAV, positivity rate in 2020-2021 (0%, n = 0) was significantly different from 2018-2019 (12.4%, n = 17) (p < 0.001) and 2019-2020 (15.4%, n = 19) (p < 0.001). IBV positivity rate in 2020-2021 (0%, n = 0) was not significantly different from previous periods. RSV occurrence was significantly lower in 2020-2021 (3.2%, n = 3), compared to 2017-2018 (15.0%, n = 15) (p = 0.006), 2018-2019 (16.1%, n = 22) (p = 0.002) and 2019-2020 (22.8%, n = 28) (p < 0.001). The RSV (winter) peak was absent and presented later (March-April 2021). Positivity rate of parainfluenza virus 3 (PIV-3) was significantly higher in 2020-2021 (11.8%, n = 11) than 2017-2018 (1%, n = 1) (p = 0.002). PIV-3 was absent from April 2020 to January 2021, whereas no clear seasonal pattern was distinguished the other years. For the other viruses tested, no significant differences in occurrence were observed between 2020-2021 and previous periods. From March 2020 onwards, 20 cases (0.7%) of SARS-CoV-2 were identified.

Conclusion

These findings reinforce the hypothesis of NPIs impacting the epidemiology of influenza viruses and RSV in young children. Compared to previous periods, no IAV and IBV cases were observed in the 2020-2021 study period, and the RSV peak occurred later. Since the pandemic is still ongoing, continuation of epidemiological surveillance, even on a larger scale, is indicated.

A machine learning COVID-19 mass screening based on symptoms and a simple olfactory test

The early detection of symptoms and rapid testing are the basis of an efficient screening strategy to control COVID-19 transmission. The olfactory dysfunction is one of the most prevalent symptom and in many cases is the first symptom. This study aims to develop a machine learning COVID-19 predictive tool based on symptoms and a simple olfactory test, which consists of identifying the smell of an aromatized hydroalcoholic gel. A multi-centre population-based prospective study was carried out in the city of Reus (Catalonia, Spain). The study included consecutive patients undergoing a reverse transcriptase polymerase chain reaction test for presenting symptoms suggestive of COVID-19 or for being close contacts of a confirmed COVID-19 case. A total of 519 patients were included, 386 (74.4%) had at least one symptom and 133 (25.6%) were asymptomatic. A classification tree model including sex, age, relevant symptoms and the olfactory test results obtained a sensitivity of 0.97 (95% CI 0.91–0.99), a specificity of 0.39 (95% CI 0.34–0.44) and an AUC of 0.87 (95% CI 0.83–0.92). This shows that this machine learning predictive model is a promising mass screening for COVID-19.

Hydrocarbon-Based Statistical Copolymers Outperform Block Copolymers for Stabilization of Ethanol-Water Foams

Well-defined block copolymers have been widely used as emulsifiers, stabilizers, and dispersants in the chemical industry for at least 50 years. In contrast, nature employs amphiphilic proteins as polymeric surfactants whereby the spatial distribution of hydrophilic and hydrophobic amino acids within the polypeptide chains is optimized for surface activity. Herein, we report that polydisperse statistical copolymers prepared by conventional free-radical copolymerization can provide superior foaming performance compared to the analogous diblock copolymers. A series of predominantly (meth)acrylic comonomers are screened to identify optimal surface activity for foam stabilization of aqueous ethanol solutions. In particular, all-acrylic statistical copolymers comprising trimethylhexyl acrylate and poly(ethylene glycol) acrylate, P(TMHA-stat-PEGA), confer strong foamability and also lower the surface tension of a range of ethanol-water mixtures to a greater extent than the analogous block copolymers. For ethanol-rich hand sanitizer formulations, foam stabilization is normally achieved using environmentally persistent silicone-based copolymers or fluorinated surfactants. Herein, the best-performing fully hydrocarbon-based copolymer surfactants effectively stabilize ethanol-rich foams by a mechanism that resembles that of naturally-occurring proteins. This ability to reduce the surface tension of low-surface-energy liquids suggests a wide range of potential commercial applications.

SAfE transport: wearing face masks significantly reduces the spread of COVID-19 on trains

COVID-19 has had a substantial impact globally. It spreads readily, particularly in enclosed and crowded spaces, such as public transport carriages, yet there are limited studies on how this risk can be reduced. We developed a tool for exploring the potential impacts of mitigation strategies on public transport networks, called the Systems Analytics for Epidemiology in Transport (SAfE Transport). SAfE Transport combines an agent-based transit assignment model, a community-wide transmission model, and a transit disease spread model to support strategic and operational decision-making. For this simulated COVID-19 case study, the transit disease spread model incorporates both direct (person-to-person) and fomite (person-to-surface-to-person) transmission modes. We determine the probable impact of wearing face masks on trains over a seven day simulation horizon, showing substantial and statistically significant reductions in new cases when passenger mask wearing proportions are greater than 80%. The higher the level of mask coverage, the greater the reduction in the number of new infections. Also, the higher levels of mask coverage result in an earlier reduction in disease spread risk. These results can be used by decision makers to guide policy on face mask use for public transport networks.

Evaluation of the Efficiency of Hand Hygiene Technique with Hydroalcoholic Solution by Image Color Summarize

Background and Objectives: The HH (hand hygiene) technique is relatively simple. Even so, in practice there are still non-conformities regarding this aspect. Lack of knowledge or lack of compliance can be reasons for non-adherence with HH techniques. In this context, the purpose of this study was to follow the realization of the hand-washing technique with hydroalcoholic solution, applied before and after receiving the HH recommendations. Materials and Methods: A descriptive, cross-sectional study was conducted from May 2022 to June 2022. Students from a second year dental medicine class teaching in French 2021/22 “Grigore T. Popa” University of Medicine and Pharmacy in Iasi were included in the study. The approval of the ethics commission was received: No. 184/05.05.2022. The study was conducted in two stages. In the first stage, HH was performed without any recommendation. In the second stage, the antiseptic hand rubbing technique was presented following the WHO recommendations. The fluorescent Fluo-Add solution, Wood lamp for dermatology (4 × 5.5 W ultraviolet tubes with a wavelength of 360 nm), and photo camera were used. Subjects performed their HH movement before and after receiving instructions according to WHO. Images were initially taken from the backhand and palm and were finally analyzed with Image Color Summarizer. The data were analyzed by the Mann–Whitney U Test, t-test paired samples using IBM-SPSS version 26 (IBM, Armonk, NY, USA), and p ≤ 0.05 was considered statistically significant. Results: After analyzing the images, there were 70 subjects, 45.7% (32) female and 54.33% (38) male. Final average covered area of backhand was 60.89% (±17.17), 28.84:86.11, compared to 52.07% (±17.04), 9:85.23. Final average covered area for palm was 69.91% (±13.5), 31.61:93.41 compared to 59.74% (±16.64), 26.13:92.72. No statistical significance was obtained by gender. Conclusions: The study showed an improvement in hand hygiene technique without highlighting gender differences.

Disinfectants against SARS-CoV-2: A Review

The pandemic due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has emerged as a serious global public health issue. Besides the high transmission rate from individual to individual, indirect transmission from inanimate objects or surfaces poses a more significant threat. Since the start of the outbreak, the importance of respiratory protection, social distancing, and chemical disinfection to prevent the spread of the virus has been the prime focus for infection control. Health regulatory organizations have produced guidelines for the formulation and application of chemical disinfectants to manufacturing industries and the public. On the other hand, extensive literature on the virucidal efficacy testing of microbicides for SARS-CoV-2 has been published over the past year and a half. This review summarizes the studies on the most common chemical disinfectants and their virucidal efficacy against SARS-CoV-2, including the type and concentration of the chemical disinfectant, the formulation, the presence of excipients, the exposure time, and other critical factors that determine the effectiveness of chemical disinfectants. In this review, we also critically appraise these disinfectants and conduct a discussion on the role they can play in the COVID-19 pandemic.

Assessment of Anti-Bacterial Effectiveness of Hand Sanitizers Commonly Used in South Africa

Hand sanitizers are used as an alternative to hand washing to reduce the number of viable microorganisms when soap and water are not readily available. This study aimed to investigate the anti-bacterial effectiveness of commercially available hand sanitizers and those commonly used in healthcare and community settings. A mapping exercise was done to select and procure different hand sanitizers (n = 18) from retailers. Five microorganisms implicated in hospital-acquired infections were selected and tested against each hand sanitizer: Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Staphylococcus aureus. Twenty-one volunteers were recruited to do a handprint before and after applying the hand sanitizer. Only four out of eighteen hand sanitizers (22%) were effective against all tested bacterial species, and an equal number (22%) were completely ineffective. Seven hand sanitizers with a label claim of 99.99% were only effective against E. coli. Only five hand sanitizers (27%) effectively reduced bacteria on participants’ hands. This study showed that only a fifth of hand sanitizers were effective against selected microorganisms. The findings raise a concern about the effectiveness of hand sanitizers and their role in infection, prevention, and control if not well regulated.

[Hand hygiene and pandemic. Controversies]

Durante la pandemia de COVID-19 los sistemas sanitarios mundiales han estado tensionados de forma extrema. Las unidades de cuidados intensivos se situaron al límite de su capacidad y los centros sanitarios se vieron obligados a habilitar espacios para atender a pacientes críticos. Los profesionales requirieron trabajar en condiciones extenuantes alterando completamente sus rutinas de trabajo.

En este escenario, la higiene de las manos y el uso de guantes de los profesionales asistenciales se convirtieron en puntos críticos del riesgo de transmisión de infecciones relacionadas con la asistencia sanitaria.

Los resultados del estudio ENVIN de los años 2020 y 2021, correspondientes al momento pandémico, arrojaron datos preocupantes de crecimiento de las tasas de infección asociadas a dispositivos invasivos, llegando a constatar aumentos del 250% de las tasas en los peores momentos de la pandemia. Esto hizo pensar que se estaban produciendo excesivas situaciones de riesgo para el paciente. Cualquier estrategia preventiva debe situar la correcta higiene de manos y el uso adecuado de los guantes dentro de sus objetivos prioritarios. Por este motivo, el Consejo Asesor de los Proyectos Zero realizó una serie de adaptaciones y recomendaciones basadas en la evidencia disponible y en la opinión de expertos relacionadas con ambas medidas durante la situación de pandemia, y así favorecer las mejores prácticas en situaciones extremas. El objetivo de este artículo es revisar los aspectos clave relacionados con la higiene de manos, siempre enmarcada en la estrategia de seguridad de la OMS, las principales barreras para su cumplimiento, y la formulación de las principales adaptaciones propuestas por el Consejo Asesor de los proyectos Zero.

A novel inactivated virus system (InViS) for a fast and inexpensive assessment of viral disintegration

The COVID-19 pandemic has caused considerable interest worldwide in antiviral surfaces, and there has been a dramatic increase in the research and development of innovative material systems to reduce virus transmission in the past few years. The International Organization for Standardization (ISO) norms 18,184 and 21,702 are two standard methods to characterize the antiviral properties of porous and non-porous surfaces. However, during the last years of the pandemic, a need for faster and inexpensive characterization of antiviral material was identified. Therefore, a complementary method based on an Inactivated Virus System (InViS) was developed to facilitate the early-stage development of antiviral technologies and quality surveillance of the production of antiviral materials safely and efficiently. The InViS is loaded with a self-quenched fluorescent dye that produces a measurable increase in fluorescence when the viral envelope disintegrates. In the present work, the sensitivity of InViS to viral disintegration by known antiviral agents is demonstrated and its potential to characterize novel materials and surfaces is explored. Finally, the InViS is used to determine the fate of viral particles within facemasks layers, rendering it an interesting tool to support the development of antiviral surface systems for technical and medical applications.

Hand hygiene with hand sanitizer versus handwashing: what are the planetary health consequences?

In order to reduce the transmission of pathogens, and COVID-19, WHO and NHS England recommend hand washing (HW) and/or the use of hand sanitizer (HS). The planetary health consequences of these different methods of hand hygiene have not been quantified. A comparative life cycle assessment (LCA) was carried out to compare the environmental impact of the UK population practising increased levels of hand hygiene during the COVID-19 pandemic for 1 year. Washing hands with soap and water was compared to using hand sanitizer (both ethanol and isopropanol based sanitizers were studied). The isopropanol-based HS had the lowest environmental impact in 14 out of the 16 impact categories used in this study. For climate change, hand hygiene using isopropanol HS produced the equivalent of 1060 million kg CO₂, compared to 1460 million for ethanol HS, 2300 million for bar soap HW, and 4240 million for liquid soap HW. For both the ethanol and isopropanol HS, the active ingredient was the greatest overall contributing factor to the environmental impact (83.24% and 68.68% respectively). For HW with liquid soap and bar soap, there were additional contributing factors other than the soap itself: for example tap water use (28.12% and 48.68% respectively) and the laundering of a hand towel to dry the hands (10.17% and 17.92% respectively). All forms of hand hygiene have an environmental cost, and this needs to be weighed up against the health benefits of preventing disease transmission. When comparing hand sanitizers to handwashing with soap and water, this study found that using isopropanol based hand sanitizer is better for planetary health. However, no method of hand hygiene was ideal; isopropanol had a greater fossil fuel resource use than ethanol based hand sanitizer. More research is needed to find hand hygiene sources which do not diminish planetary health, and environmental impact is a consideration for public health campaigns around hand hygiene.

Green Synthesis of Silver Nanoparticles Coated by Water Soluble Chitosan and Its Potency as Non-Alcoholic Hand Sanitizer Formulation

The synthesis of silver nanoparticles using plant extracts, widely known as a green synthesis method, has been extensively studied. Nanoparticles produced through this method have applications as antibacterial agents. Bacterial and viral infection can be prevented by use of antibacterial agents such as soap, disinfectants, and hand sanitizer. Silver nanoparticles represent promising hand sanitizer ingredients due to their antibacterial activity and can enable reduced use of alcohol and triclosan. This study employed silver nanoparticles synthesized using Kepok banana peel extract (Musa paradisiaca L.). Nanoparticle effectiveness as a hand sanitizer can be enhanced by coating with a biocompatible polymer such as chitosan. The characterization of silver nanoparticles was conducted using UV-Vis, with an obtained peak at 434.5 nm. SEM-EDX analysis indicated nanoparticles with a spherical morphology. Silver nanoparticles coated with chitosan were characterized through FTIR to verify the attached functional groups. Gel hand sanitizers were produced using silver nanoparticles coated with different chitosan concentrations. Several tests were undertaken to determine the gel characteristics, including pH, syneresis, and antibacterial activity. Syneresis leads to unstable gels, but was found to be inhibited by adding chitosan at a concentration of 2%. Antibacterial activity was found to increase with increase in chitosan concentration.

Application of a headspace GC-MS method to evaluate the product quality of alcohol-based wipe hand sanitizers (ABHS)

The investigation of marketed wipe hand sanitizers presented an analytical challenge due to the extraction from the solid matrix of the products. The present work describes the development of a new sample preparation method for the extraction of analytes from wipe hand sanitizer matrix into dimethyl sulfoxide for analysis by headspace GCMS. ABHS wipe products labeled to contain ethanol or isopropanol as active ingredients were tested, varying in the size and weight of the wipes. The spike recovery assay was confirmed using spiking solutions containing the impurities at concentrations equivalent to 50%, 100% and 200% of the interim concentration limits. All tested analytes showed recovery within the allowable limits (80%-120%). Six marketed ABHS wipe products were tested and no impurities above the FDA interim limits were observed. One product contained ethanol below the 60% v/v limit and another product was mislabeled for isopropanol and was found to contain ethanol instead. Four of the six ABHS products did not meet the label claim, which may affect the product quality. The analytical method and sample preparation procedures will provide the FDA and ABHS manufacturers with the capability to conduct quality assurance testing of wipe hand sanitizers for active ingredient content and impurities.

Comprehensive Review on Applications of Surfactants in Vaccine Formulation, Therapeutic and Cosmetic Pharmacy and Prevention of Pulmonary Failure due to COVID-19

Our world is under serious threat of environmental degradation, climate change and in association with this the out breaks of diseases as pandemics. The devastating impact of the very recent COVID-19, The sharp increase in cases of Cancer, Pulmonary failure, Heart health has triggered questions for the sustainable development of pharmaceutical and medical sciences. In the search of inclusive and effective strategies to meet today’s demand, improvised methodologies and alternative green chemical, bio-based precursors are being introduced by scientists around the globe. In this extensive review we have presented the potentiality and Realtime applications of both synthetic and bio-based surfactants in bio-medical and pharmaceutical fields. For their excellent unique amphoteric nature and ability to solubilise in both organic and inorganic drugs, surfactants are one of the most potential candidates for bio-medicinal fields such as dermatology, drug delivery, anticancer treatment, surfactant therapy, vaccine formulation, personal hygiene care and many more. The self-assembly property of surfactants is a very powerful function for drug delivery systems that increases the bio-availability of the poorly aqueous soluble pharmaceutical products by influencing their solubility. Over the decades many researchers have reported the antimicrobial, anti-adhesive, antibiofilm, anti-inflammatory, antioxidant activities of surfactants regarding its utility in medicinal purposes. In some reports surfactants are found to have spermicidal and laxative activity too. This comprehensive report is targeted to enlighten the versatile applications of Surfactants in drug delivery, vaccine formulation, Cancer Treatment, Therapeutic and cosmetic Pharmaceutical Sciences and prevention of pulmonary failure due to COVID-19.

Differences in environmental stability among SARS-CoV-2 variants of concern: Both Omicron BA.1 and BA.2 have higher stability

Objectives

The increased infectivity and transmissibility of SARS-CoV-2 variants of concern (VOCs) could cause significant human and economic damage. Hence, understanding their characteristics is crucial to control infection. We evaluated the environmental stability of the Wuhan strain and all VOCs (Alpha, Beta, Gamma, Delta, Omicron BA.1, and Omicron BA.2 variants) on plastic and human skin surfaces and their disinfection efficacy.

Methods

To evaluate environmental stability, residual virus titres on plastic and human skin surfaces were measured over time. Their survival time and half-life were calculated using regression analysis. The effectiveness of ethanol-based disinfectants at different concentrations was determined by in vitro and ex vivo evaluations.

Results

On plastic and skin surfaces, the Alpha, Beta, Delta, and Omicron variants exhibited approximately two-fold longer survival times than the Wuhan strain; the Omicron variants had the longest survival time. The median survival times of the Wuhan strain and the Alpha, Beta, Gamma, Delta, and Omicron (BA.1 and BA.2) variants on human skin surface were 8.6, 19.6, 19.1, 11.0, 16.8, 21.1, and 22.5 h, respectively. The in vitro evaluation showed that the Wuhan strain and the Alpha, Beta, Gamma, Delta, and Omicron (BA.1 and BA.2) variants were completely inactivated within 15 s by 32.5%, 35%, 35%, 32.5%, 35%, 40%, and 40% ethanol, respectively. However, all viruses on human skin were completely inactivated by exposure to 35% ethanol for 15 s.

Conclusions

SARS-CoV-2 VOCs, especially the Omicron variants, have higher environmental stability than the Wuhan strain, increasing their transmission risk and contributing to their spread.

Use of ultraviolet light in graduate medical education to assess confidence among residents and fellows in handwashing instruction

BACKGROUND

Coronavirus disease 2019 (COVID-19) has made it imperative to focus on strategies to improve hand hygiene to minimize threats of viral transmission in hospitals.

OBJECTIVE

We investigated the potential of using ultraviolet (UV) light as a visual tool in hand-hygiene education to bring awareness of individual handwashing effectiveness to healthcare workers.

METHODS

In 2020, 117 individuals participated in the simulation and completed surveys on proper handwashing technique. Of these, 114 were first-year residents and fellows. Surveys of confidence in hand hygiene were obtained before and after formal hand-hygiene education utilizing UV light with Glo Germ lotion. The UV light and Glo Germ lotion were used to identify deficiencies in individual handwashing technique.

RESULTS

With a total response rate of 97.4%, first-year residents and fellows demonstrated a significant decrease in handwashing confidence in pre- and posteducation surveys. Study participants who had had formal hand-hygiene training in the previous 3 years also indicated confidence in hand hygiene similar to those who had not had previous hand-hygiene training. Conclusions: Overall, resident interns and fellows may have falsely elevated their hand-hygiene confidence levels. However, conclusions regarding the confidence of residents and fellows individually could not be made due to sample size. Many healthcare personnel practice improper handwashing techniques, which may be improved with education and training that includes UV light.

Assessment of quality of alcohol-based hand sanitizers used in Johannesburg area during the CoViD-19 pandemic

Since the outbreak of the Coronavirus Disease 2019 (CoViD-19), the World Health Organization has recommended that, in absence of soap and water, alcohol-based hand sanitizer can be used to prevent the transmission of coronaviruses. Unfortunately, many media and anecdotal reports indicate that many alcohol-based hand sanitizers sold in South Africa are substandard and some contain potentially toxic ingredients. The study aimed to identify hand sanitizers used in the Johannesburg area during the CoViD-19 pandemic that do not contain the recommended alcohol concentration of at least 70% propanol or 60% ethanol, and contain traces of toxic ingredients. Hand sanitizers randomly collected from various traders around Johannesburg were analyzed using Agilent auto sampler coupled to a gas chromatograph utilizing flame ionisation detection. Of the 94 hand sanitizer samples collected, three preparations contained no alcohol, whereas the rest contained either ethanol, 2-propanol or 1-propanol or a combination of two alcohols. Of the alcohol-containing hand sanitizers, 37 (41%) contained less than 60% alcohol. Ethyl acetate, isobutanol and other non-recommended alcohols (methanol and 3-methyl-butanol) were also identified. Consumers are therefore warned that among the many brands of hand sanitizers found around Johannesburg, there are some substandard preparations and some that contain traces of toxic ingredients.

Deciphering Ethanol-Driven Swelling, Rupturing, Aggregation, and Fusion of Lipid Vesicles Using Coarse-Grained Molecular Dynamics Simulations

Traditionally, liquid ethanol is known to enhance the permeability of lipid membranes and causes vesicle aggregation and fusion. However, how the amphiphilic ethanol molecules perturb the lipid vesicles to facilitate their aggregation or fusion has not been addressed at any level of molecular simulations. Herein, not only have we developed a coarse-grained (CG) model for liquid ethanol, its aqueous mixture, and hydrated lipid membranes for molecular dynamics (MD) simulations, but also utilized it to delineate the aggregation and fusion of lipid vesicles using CG-MD simulations with multimillion particles. We have systematically parametrized the force-field for pure ethanol and its interactions with hydrated POPC and POPE model lipid membranes. In this process, we have successfully reproduced the bulk ethanol structure and concentration-dependent density of aqueous ethanol. To quantify the interaction of ethanol with lipid membranes, we have reproduced the transfer free energy of the ethanol molecule across the hydrated bilayers, and the concentration-dependent distribution of ethanol molecules across the lipid bilayers. After having acceptable force-field parameters for ethanol-membrane interactions, we have checked the effect of ethanol toward the vesicles comprising POPC lipids. We observe a rapid increase in the size of the POPC lipid vesicles with increasing amounts of ethanol up to 30 mol %. We unambiguously observe swelling and decrease in the thickness of the POPC vesicles with increasing amounts of ethanol up to 30 mol %, beyond which the vesicles begin to lose their integrity and rupture at higher mol % of ethanol. The fusion study of two vesicles demonstrates that fused vesicles can be obtained from 20 to 30 mol % of ethanol provided that they are brought closer than a critical distance at a particular mol %. The multivesicle simulations show that along with the increase in the sizes of vesicles the propensity of vesicle aggregation increases as the mol % of ethanol increases.