Influence of glycerol and an alternative humectant on the immediate and 3-hours bactericidal efficacies of two isopropanol-based antiseptics in laboratory experiments in vivo according to EN 12791

A critical evaluation of contents, labeling, and cost of hand sanitizers marketed in India during COVID-19 pandemic

Background

Antiseptics were introduced a long time ago, but their significance was noteworthy during the COVID-19 pandemic. Hand sanitizer plays a pivotal role as a preventive measure. Multiple national authorities have advocated for the application of Alcohol-Based Hand Sanitizers (ABHS). During the pandemic, a surge in demand and limited supply prompted numerous manufacturers to ramp up production. Consequently, it is imperative to scrutinize the composition, labeling, and price of hand sanitizers.

Aims and Objective

To assess the contents, labeling, and price of hand sanitizers available in the Indian market.

Methodology

Hand sanitizers, both online and offline, marketed in India between May 2019 and May 2022 were included. Hand sanitizers by local manufacturers without labeling were excluded. Contents and labeling of hand sanitizers were evaluated as per World Health Organization (WHO) recommendations. Price was assessed as a percentage cost variation.

Result

Out of 79, the majority (98.73%) were ABHS, and 28.20% of them met the recommended criteria for "Adequate" alcohol concentration. Ethyl alcohol emerged as the most prevalent (69.23%), often accompanied by emollients, humectants, fragrances, and color additives. Notably, 69.62% of the hand sanitizers featured comprehensive labeling, while incomplete labels lacked essential details under "Warning and Cautions." The average price of hand sanitizers was Rs 505.11 ± 255.36.

Conclusion

Choosing ABHS with appropriate alcohol concentrations in line with recommendations is crucial. To ensure the proper and safe use of hand sanitizers, individuals should follow the instructions provided on the product labels; both manufacturers and regulators are responsible for adhering to standards for hand sanitizers made available to the public.

A comparative study on the effect of alcohol-based hand sanitizers in spray and gel formulation on the skin: A prospective, randomised, crossover trial

BACKGROUND

Many formulations of Alcohol-based hand rubs (ABHRs), such as liquid, gel, and spray have been developed and used for preventing infections. This study aimed to compare skin irritation from using ABHRs in gel and spray formulations.

METHOD

This was a prospective, randomised, crossover trial conducted to investigate the effect of skin irritation caused by ABHRs in gel compared to spray formulation after 21 days of using each formulation. Clinical outcomes were assessed using subjective Larson's skin assessment score and Frosch and Kligman observer skin assessment score, as well as bioengineering measures: transepidermal water loss (TEWL) and skin capacitance on days 3, 7, 14, and 21.

RESULTS

Among 38 participants, both formulations showed no significant change in clinical scores and skin capacitance during the study. However, TEWL increased significantly from baseline on day 3 (p = 0.029) for the spray formulation and on day 21 (p = 0.019) for the gel formulation, with no statistically significant difference between the formulations (p = 0.46).

CONCLUSION

Our research supports the safety of gel and spray ABHRs for regular use, with the only potential issue being mild skin irritation. For those with sensitive skin, the gel formulation is preferable.

Acceptability of an alcohol-based handrub gel with superfatting agents among healthcare workers: a randomized crossover controlled study

Introduction

Healthcare workers often experience skin dryness and irritation from performing hand hygiene frequently. Low acceptability and tolerability of a formulation are barriers to hand hygiene compliance, though little research has been conducted on what specific types of formulation have higher acceptability than others.

Objective

To compare the acceptability and tolerability of an ethanol-based handrub gel with superfatting agents to the isopropanol-based formulations (a rub and a gel formulation) currently used by healthcare workers at the University of Geneva Hospitals, Geneva, Switzerland.

Methods

Forty-two participants were randomized to two sequences, testing the isopropanol-based formulation that they are using currently (Hopirub® or Hopigel®), and the ethanol-based formulation containing superfatting agents (Saniswiss Sanitizer Hands H1). Participants tested each of the formulations over 7–10 day work shifts, after which skin condition was assessed and feedback was collected.

Results

H1 scored significantly better than the control formulations for skin dryness (P = 0.0209), and participants felt less discomfort in their hands when using that formulation (P = 0.0448). H1 caused less skin dryness than Hopirub®/Hopigel® (P = 0.0210). Though overall preference was quite polarized, 21 participants preferred H1 intervention formulation and 17 preferred the Hopirub®/Hopigel® formulation that they normally used in their care activities.

Conclusion

We observed a difference in acceptability and strongly polarized preferences among the participants' reactions to the formulations tested. These results indicate that giving healthcare workers a choice between different high-quality products is important to ensure maximum acceptability.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-022-01129-4.

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 disinfectant efficacy in reducing microbial growth

The incidence of hospital- and community-acquired infections has been dramatically increased worldwide. Accordingly, hands hygiene and the use of disinfectants have been increased leading to the expansion in hand sanitizers production to meet public demand. This study was conducted to assess the efficiency of common disinfectants in the market of Riyadh, Saudi Arabia in inhibiting the microbial growth during the time of Coronavirus disease 2019 (COVID-19) pandemic. Five bacterial strains of commonly hospital-acquired infections (Pseudomonas aeruginosa, Escherichia coli, Salmonella enteritidis, Staphylococcus aureus, and Enterococcus faecalis) (ATCC reference strains and clinical isolates) were examined for their susceptibility against 18 disinfectants collected from the Saudi market. The tested 18 disinfectants were broadly clustered into different groups based on their active chemical composition as following: 12 products contained alcohol, 2 products had chlorhexidine, 3 products contained mixed concentration of alcohol/chlorhexidine and 1 product had a mixture of chlorhexidine/Hexamidine/Chlorocresol. By measuring the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC), our results revealed that all the 18 disinfectants have reduced the microbial growth of all the tested strains. Generally, the MICs and the MBCs for the clinical strains are higher than those of the reference strains. Taken together, our findings showed that all tested products have high disinfectants’ killing rate against microbes of different origins, which suggest the high quality of these disinfectants and the good surveillance practice by the local authorities in Saudi Arabia.

A Fresh Look at Mouthwashes-What Is Inside and What Is It For?

Mouthwashes are a very popular additional oral hygiene element and there are plenty of individual products, whose compositions are in a state of flux. The aim of our study was to investigate the compositions of mouthwashes and their functions, as well as to discuss their effectiveness in preventing and curing oral diseases and side effects. We searched for mouthwashes available on the market in Poland. We identified 241 individual mouthwash products. The extraction of compositions was performed and functions of the ingredients were assessed. Then, analysis was performed. The evaluation revealed that there are plenty of ingredients, but a typical mouthwash is a water–glycerine mixture and consists of additional sweetener, surfactant, preservative, and some colourant and flavouring agent, as well as usually having two oral health substances, anticaries sodium fluoride and antimicrobial essential oils. The effectiveness or side effects of several substances of mouthwashes were thoroughly discussed. We recommend not multiplying individual mouthwash products and their ingredients beyond medical or pharmaceutical necessity, especially without scientific proof.

Topical Antiseptic Formulations for Skin and Soft Tissue Infections

Skin and soft tissue infections (SSTIs) are usually acute conditions of inflammatory microbial occupation of the skin layers and underlying soft tissues. SSTIs are one of the most frequent types of infection, typically requiring medical intervention and contribute to morbidity and mortality in both primary care and hospitalised patients. Due to the dramatic rise of antibiotic resistance, antiseptic agents can be potential alternatives for the prevention and treatment of SSTIs. Notably, they are commonly recommended in many global practical guidelines for use in per- and post- operative procedures. A range of antiseptics, including chlorhexidine, triclosan, alcohol, and povidone-iodine, are used and are mainly formulated as traditional, simple dosage forms such as solutions and semi-solids. However, in recent years, there have been studies reporting the potential for nanotechnology in the delivery of antiseptics. In this review, we have collated the scientific literature that focuses on topical antiseptic formulations for prevention and treatment of SSTIs, and have divided findings into traditional and advanced formulations. We conclude that although nanotechnological formulations have demonstrated potential advantages for delivering drugs; nevertheless, there is still scope for traditional formulations and further development of optimised topical formulations to address the rise of antimicrobial resistance.

Hydrogels in Hand Sanitizers

Hand hygiene can be considered a strategic key useful in the containment of infections such as COVID-19 both at home and in communities because it can dramatically reduce the widespread outbreak of infections. In case of the unavailability of soap and water, "instant" hand sanitizers are recommended because their application can be considered easy, versatile, quick and often less aggressive for the skin. For these reasons, alcoholic and alcohol-free hand rub gels can be considered the best performing formulations on the market. Together with disinfectants and antiseptic agents, hydrogels play a fundamental role in obtaining stable formulations and are easy to disperse, with a pleasant skin feel and an overall good performance. Several compounds commonly used in the pharmaceutical, cosmetic and food industry are available for this purpose, in particular, cellulose derivatives and synthetic polymers derivatives. Each of them is available in several grades, presenting different thickening behavior, rheological properties and compatibility with other ingredients, alcohols in particular. For all these reasons, it is important to explore hydrogel properties and behaviors in different contexts (i.e., hydroalcoholic and aqueous media) in order to develop new and performing hand rub gels, always taking into account the different international legal frameworks regarding disinfectant and sanitizing formulations.

SARS-CoV-2 decontamination of skin with disinfectants active during and after application

Background

The coronavirus disease 2019 pandemic has resulted in high levels of exposure of medical workers to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Hand decontamination is one of the actions recommended to reduce the risk of infection.

Aim

Two disinfectants – BIAKŌS antimicrobial skin and wound cleanser (AWC) and AWC2 (Sanara MedTech, Fort Worth, TX, USA) – were tested to determine whether they can inactivate SARS-CoV-2 upon contact or as a coating applied before contact with the virus.

Methods

The ability of AWC and AWC2 to inactivate SARS-CoV-2 was tested in liquid and dried form on plastic surfaces and porcine skin.

Findings

AWC and AWC2 were effective in reducing the infectious titre of SARS-CoV-2 in liquid form during application and in dried form 4 h after application. Virus on skin was reduced up to 2 log₁₀-fold and 3.5 log₁₀-fold after treatment with AWC and AWC2, respectively.

Conclusion

Application of AWC and AWC2 to skin reduces the level of SARS-CoV-2 and the risk of infection.

Alcohol-based hand sanitisers as first line of defence against SARS-CoV-2: a review of biology, chemistry and formulations

The pandemic due to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has emerged as a serious global public health issue. Since the start of the outbreak, the importance of hand-hygiene and respiratory protection to prevent the spread of the virus has been the prime focus for infection control. Health regulatory organisations have produced guidelines for the formulation of hand sanitisers to the manufacturing industries. This review summarises the studies on alcohol-based hand sanitisers and their disinfectant activity against SARS-CoV-2 and related viruses. The literature shows that the type and concentration of alcohol, formulation and nature of product, presence of excipients, applied volume, contact time and viral contamination load are critical factors that determine the effectiveness of hand sanitisers.

Hand sanitisers amid CoViD-19: A critical review of alcohol-based products on the market and formulation approaches to respond to increasing demand

The world is facing a medical crisis amid the CoViD-19 pandemic and the role of adequate hygiene and hand sanitisers is inevitable in controlling the spread of infection in public places and healthcare institutions. There has been a great surge in demand for hand sanitisation products leading to shortages in their supply. A consequent increase of substandard products in the market has raised safety concerns. This article, therefore, presents a critical review of hand sanitation approaches and products available on the market in light of the scientific evidence available to date. This review also provides a range of hand sanitisation product formulations, and manufacturing instructions to allow for extemporaneous preparations at the community and hospital pharmacies during this urgent crisis. In addition, this emergent situation is expected to continue, hence hand sanitisers will be in demand for an extended time, and the availability and purchase of substandard products on the market create an ongoing safety concern. Therefore, this article shall also provide various commercial organisations, interested in stepping forward the production and marketing of hand sanitisers, with a guide on the development of products of standardised ingredients and formulations.

Glycerol content within the WHO ethanol-based handrub formulation: balancing tolerability with antimicrobial efficacy

Background

The World Health Organization (WHO) ethanol-based handrub (EBHR) formulation contains 1.45% glycerol as an emollient to protect healthcare workers' (HCWs) skin against dryness and dermatitis. However, glycerol seems to negatively affect the antimicrobial efficacy of alcohols. In addition, the minimal concentration of glycerol required to protect hands remain unknown. We aim to evaluate the tolerance of HCWs to the WHO EBHR formulation using different concentrations of glycerol in a tropical climate healthcare setting.

Methods

We conducted a cluster-randomized, double-blind, crossover study among 40 HCWs from an intensive care unit of a tertiary-care hospital in Brazil, from June 1st to September 30, 2017. We tested the WHO EBHR original formulation containing 1.45% glycerol against three other concentrations (0, 0.5, and 0.75%). HCWs used one formulation at a time for seven working days during their routine practice and then had their hands evaluated by an external observer using the WHO scale for visual inspection. Participants also used a WHO self-evaluation tool to rate their own skin condition. We used a generalized estimating equations of the logit type to compare differences between the tolerability to different formulations.

Results

According to the independent observation, participants had 2.4 times (95%CI: 1.12-5.15) more chance of having a skin condition considered good when they used the 0.5% compared to the 1.45% glycerol formulation. For the self-evaluation scale, participants were likely to have a worst evaluation (OR: 0.23, 95%CI: 0.11-0.49) when they used the preparation without glycerol compared to the WHO standard formulation (1.45%), and there were no differences between the other formulations used.

Conclusion

In a tropical climate setting, the WHO-modified EBHR formulation containing 0.5% glycerol led to better ratings of skin tolerance than the original formulation, and, therefore, may offer the best balance between skin tolerance and antimicrobial efficacy.

Chlorhexidine-coated surgical gloves influence the bacterial flora of hands over a period of 3 hours

Background

The risk of SSI increases in the presence of foreign materials and may be caused by organisms with low pathogenicity, such as skin flora derived from hands of surgical team members in the event of a glove breach. Previously, we were able to demonstrate that a novel antimicrobial surgical glove coated chlorhexidine-digluconate as the active ingredient on its inner surface was able to suppress surgeons' hand flora during operative procedures by a magnitude of 1.7 log₁₀ cfu/mL. Because of the clinical design of that study, we were not able to measure the full magnitude of the possible antibacterial suppression effect of antimicrobial gloves over a full 3 h period.

Methods

The experimental procedure followed the method for assessment of the 3-h effects of a surgical hand rub's efficacy to reduce the release of hand flora as described in the European Norm EN 12791. Healthy volunteers tested either an antimicrobial surgical glove or non-antimicrobial surgical latex gloves in a standardized laboratory-based experiment over a wear time of 3 h.

Results

Wearing antimicrobial surgical glove after a surgical hand rub with 60% (v/v) n-propanol resulted in the highest 3-h reduction factor of 2.67 log₁₀. Non-antimicrobial surgical gloves demonstrated significantly lower (p ≤ 0.01) 3-h reduction factors at 1.96 log₁₀ and 1.68 log₁₀, respectively. Antibacterial surgical gloves are able to maintain a sustainable bacterial reduction on finger tips in a magnitude of almost 3 log₁₀ (log₁₀ 2.67 cfu) over 3 h wear time.

Conclusion

It was demonstrated that wear of an antibacterial surgical glove coated with chlorhexidine-digluconate is able to suppress resident hand flora significantly over a period of 3-h.

Glycerol Solvates DPPC Headgroups and Localizes in the Interfacial Regions of Model Pulmonary Interfaces Altering Bilayer Structure

The inclusion of glycerol in formulations for pulmonary drug delivery may affect the bioavailability of inhaled steroids by retarding their transport across the lung epithelium. The aim of this study was to evaluate whether the molecular interactions of glycerol with model pulmonary interfaces provide a biophysical basis for glycerol modifying inhaled drug transport. Dipalmitoylphosphatidylcholine (DPPC) monolayers and liposomes were used as model pulmonary interfaces, in order to examine the effects of bulk glycerol (0-30% w/w) on their structures and dynamics using complementary biophysical measurements and molecular dynamics (MD) simulations. Glycerol was found to preferentially interact with the carbonyl groups in the interfacial region of DPPC and with phosphate and choline in the headgroup, thus causing an increase in the size of the headgroup solvation shell, as evidenced by an expansion of DPPC monolayers (molecular area increased from 52 to 68 Ų) and bilayers seen in both Langmuir isotherms and MD simulations. Both small angle neutron scattering and MD simulations indicated a reduction in gel phase DPPC bilayer thickness by ∼3 Å in 30% w/w glycerol, a phenomenon consistent with the observation from FTIR data, that glycerol caused the lipid headgroup to remain oriented parallel to the membrane plane in contrast to its more perpendicular conformation adopted in pure water. Furthermore, FTIR measurements suggested that the terminal methyl groups of the DPPC acyl chains were constrained in the presence of glycerol. This observation is supported by MD simulations, which predict bridging between adjacent DPPC headgroups by glycerol as a possible source of its putative membrane stiffening effect. Collectively, these data indicate that glycerol preferentially solvates DPPC headgroups and localizes in specific areas of the interfacial region, resulting in structural changes to DPPC bilayers which may influence cell permeability to drugs.

Disinfection of artificially contaminated gloved hands reduces transmission of Staphylococcus epidermidis to catheter valves

Disinfection of gloved hands is advocated increasingly in situations where visibly unsoiled gloves are used during multiple clinical activities on the same patient. As there are no data demonstrating that such practice attributes to lower bacterial transfer during clinical care, a standardized experimental study was conducted. Gloved hands touched chicken breasts contaminated with Staphylococcus epidermidis with or without disinfection before touching sterile catheter valves. Contaminated gloves transferred 5.18 log₁₀ colony-forming units (cfu) S. epidermidis to the catheter valves. Disinfection of contaminated gloves significantly reduced the numbers transferred to 0.78 log₁₀ cfu. Disinfection of gloved hands may reduce the risk of transmission.