Comparison of In Vitro Inactivation of SARS CoV-2 with Hydrogen Peroxide and Povidone-Iodine Oral Antiseptic Rinses

Antimicrobial Activity of Hydrogen Peroxide for Application in Food Safety and COVID-19 Mitigation: An Updated Review

Hydrogen peroxide (H2O2) is a well-known agent with a broad-spectrum antimicrobial activity against pathogenic bacteria, fungi, and viruses. It is a colorless liquid and commercially available in aqueous solution over a wide concentration range. It has been extensively used in the food industry by virtue of its strong oxidizing property and its ability to cause cellular oxidative damage in microbial cells. This review comprehensively documents recent research on the antimicrobial activity of H2O2 against organisms of concern for the food industry, as well as its effect against SARS-CoV-2 responsible for the COVID-19 pandemic. In addition, factors affecting the antimicrobial effectiveness of H2O2, different applications of H2O2 as a sanitizer or disinfectant in the food industry as well as safety concerns associated with H2O2 are discussed. Finally, recent efforts in enhancing the antimicrobial efficacy of H2O2 are also outlined.

The effects of mouth rinsing and gargling with mouthwash containing povidone-iodine and hydrogen peroxide on the cycle threshold value of Severe Acute Respiratory Syndrome Coronavirus 2: A randomized controlled trial of asymptomatic and mildly symptomatic patients

Background

Coronavirus disease 2019 can spread rapidly. Surgery in the oral cavity poses a high risk of transmission of severe acute respiratory syndrome coronavirus 2. The American Dental Association and the Centers for Disease Control and Prevention recommend the use of mouthwash containing 1.5% hydrogen peroxide (H 2O 2) or 0.2% povidone iodine (PI) to reduce the viral load in the upper respiratory tract and decrease the risk of transmission. The aim of the present study was to analyze the effect of mouth rinsing and gargling with mouthwash containing 1% PI, 0.5% PI, 3% H 2O 2, or 1.5% H 2O 2 and water on the cycle threshold (CT) value obtained by real-time reverse transcription polymerase chain reaction (RT-PCR).

Methods

This study is a randomized single blind controlled clinical trial which has been registered in the International Standard Randomized Controlled Trial Number (ISRCTN) registry on the 3 rd February 2022 (Registration number: ISRCTN18356379). In total, 69 subjects recruited from Persahabatan General Hospital who met the inclusion criteria were randomly assigned to one of four treatment groups or the control group. The subjects were instructed to gargle with 15 mL of mouthwash for 30 s in the oral cavity followed by 30 s in the back of the throat, three times per day for 5 days. CT values were collected on postprocedural days 1, 3, and 5.

Results

The results of the Friedman test significantly differed among the groups (n=15). The CT values increased from baseline (day 0) to postprocedural days 1, 3, and 5.

Conclusions

Mouth rinsing and gargling with mouthwash containing 1% PI, 0.5% PI, 3% H 2O 2, or 1.5% H 2O 2 and water increased the CT value.

Effect of Preventive Dental Products on Bonding Force: An in vitro Study

Aim

Testing the effect of Fluoride, chlorhexidine, and molecular iodine applications on the mean micro-shear bond strength (SBS) of enamel in an attempt to preserve enamel integrity during the bonding process.

Materials and Methods

The study was an observational case-control one in which 150 human teeth were classified into 10 groups according to the product kind and the prescribed treatment. Each group consisted of 15 teeth. Group C was the control group. Groups FP, FV, and OS utilized products that could be utilized in a professional dental setting. Group FP was treated with 1.23% NaF prophy paste, Group FV was treated with 5% NaF varnish, and Group OS was treated with Opal® Seal Fluoride releasing primer and sealant. Groups L, LF, CHX, and I were treated with mouth rinses. Group L was treated with Listerine Zero Fluoride-Free Mouthwash, Group LF with Listerine Zero 0.02% NaF Mouth Rinse, Group CHX with 0.12% chlorhexidine gluconate, and Group I with ioRinse RTU 100 ppm molecular iodine rinse. Groups TP and G utilized alternative remineralization products. Group TP was treated with Fluoro Calcium Phosphosilicate bioglass containing toothpaste, and Group G was treated with Curodont Protect remineralizing tooth gel. One-way ANOVA test was utilized to perform all statistical analysis in this study.

Results

For mean micro-SBS, no significant difference (P > 0.05) between any of the experimental groups was observed when compared to the control group. There was a significant difference (P < 0.05) between Opal Seal versus Listerine Total, Opal Seal versus Peridex, Listerine versus Listerine Total, and Listerine versus Peridex. All other experimental group comparisons revealed a nonsignificant difference (P > 0.05).

Conclusions

As the null hypothesis (H0) assumes that changes observed in an experiment are due to chance, hence, the outcomes of this study are coherent with (H0) since the aforementioned application methods did not significantly impact the SBS of orthodontic resin cement to enamel.

Virucidal activity of a plant-oil-based oral rinse against respiratory viruses

BACKGROUND

Respiratory viruses have been reported to infect the salivary glands and the throat, which are potential reservoirs for virus replication and transmission. Therefore, strategies to reduce the amount of infective virus particles in the oral mucous membranes could lower the risk of transmission.

METHODS

The viral inactivation capacity of a plant-oil-based oral rinse (Salviathymol®) was evaluated in comparison with chlorhexidine (Chlorhexamed® FORTE) using a quantitative suspension test according to EN 14476.

FINDINGS

Salviathymol efficiently inactivated severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2), respiratory syncytial virus (RSV) and two influenza strains to undetectable levels.

CONCLUSION

Salviathymol has potential as preventive measure to lower transmission of respiratory viruses.

The effect of preprocedural mouthrinses against COVID-19 before acid etching on the microleakage of a resin-based sealant in permanent molars: An in vitro experimental study

Aim

To determine whether rinsing with preprocedural mouthrinses against coronavirus disease before acid etching affects resin-based sealant microleakage.

Materials and Methods

A presented in vitro experimental study was performed on 15 extracted permanent third molars. Samples were randomly allocated into five groups: Group 1-distilled water (control); Group 2-1% hydrogen peroxide; Group 3-1.5% hydrogen peroxide; Group 4-0.5% povidone-iodine; and Group 5-1% povidone-iodine. After the teeth were immersed in the assigned mouth rinses for 60 s, they were sealed with Concise™ white sealant. Subsequently, the teeth were thermocycled for 500 cycles, immersed in 2% methylene blue solution for 24 h, and sectioned with two parallel cuts in the buccolingual direction. Sixty surfaces (12 surfaces in each group) were examined for microleakage under a 40× light microscope and scored as described by Zyskind et al. Welch's one-way analysis of variance test and the Games-Howell test were used to analyze the results at a significance level of P < 0.05 for all tests.

Results

The intergroup comparisons indicated that the 0.5% povidone-iodine group and the 1% povidone-iodine group had significantly higher microleakage compared with the control group. The 1% and 1.5% hydrogen peroxide groups demonstrated no significant difference in mean microleakage scores compared with the control group. There was no significant difference between the povidone groups and the hydrogen peroxide groups.

Conclusions

Preprocedural rinsing with 0.5% and 1% povidone-iodine before acid etching caused higher microleakage of resin-based sealant, while hydrogen peroxide rinsing gave comparable microleakage compared with the control group.

Efficacy of different mouthwashes against COVID-19: A systematic review and network meta-analysis

To evaluate the effectiveness of antiseptic mouthwashes in reducing SARS-CoV-2 load clinically and in vitro. A systematic electronic search (MEDLINE/Scopus/Cochrane) was conducted to identify prospective clinical and in vitro studies published between 2019 included and 16 June 2023 assessing the effectiveness of mouthwashes in reducing SARS-CoV-2 load in saliva or surrogates. Data were summarized in tables and a network meta-analysis was performed for clinical trials. Thirty-five studies (14 RCTs, 21 in vitro) fulfilled the inclusion criteria. The risk of bias was judged to be high for 2 clinical and 7 in vitro studies. The most commonly test product was chlorhexidine alone or in combination with other active ingredients, followed by povidone-iodine, hydrogen peroxide and cetylpyridinium chloride. Overall, the descriptive analysis revealed the effectiveness of the mouthwashes in decreasing the salivary viral load both clinically and in vitro. Network meta-analysis demonstrated a high degree of heterogeneity. Among these studies, only chlorhexidine 0.20% was associated to a significant Ct increase in the saliva 5 min after rinsing compared to non-active control (p = 0.027). Data from clinical and in vitro studies suggested the antiviral efficacy of commonly used mouthwashes. Large well-balanced trials are needed to identify the best rinsing protocols.

In vivo efficacy of 2% povidone iodine, chlorhexidine gluconate, and herbal extract mouthwash on SARS-CoV-2 viral load in saliva: A randomized clinical trial

Background

One of the major techniques to reduce the transmission rate of COVID-19 would be to decrease the viral titers of SARS-CoV-2 in the saliva of infected patients and it is particularly useful in a dental setting. The present study evaluated the change in salivary viral load of COVID-19 patients using povidone iodine (PI), chlorhexidine (CHX), and an herbal extract (RightSure®) oral antiviral herbal mouthwash (HM) at clinically recommended duration and concentrations.

Materials and Methods

Thirty individuals with SARS-CoV-2 were randomly allocated to three groups: (1) Group 1, PI mouthwash; (2) Group 2, CHX mouthwash; and (3) Group 3, HM mouthwash. A baseline salivary throat sample was collected from all the participants who were later instructed to rinse with their respective mouthwash for 30 s. A second salivary sample was collected 30 min after rinsing. The SARS-CoV-2 viral load was analyzed using real-time reverse-transcription polymerase chain reaction wherein the cyclic threshold (Ct) values were evaluated.

Results

Independent t-test analysis reported a statistically significant difference concerning the PI group (before-after comparison) (P < 0.05). The rest of the two study groups failed to report any significant difference in the nucleocapsid gene and open reading frame 1a gene levels.

Conclusion

While all three types of mouthwash increased the Ct values, a statistically significant difference was observed with PI mouthwash, indicating that it might potentially reduce the spread of the SARS-CoV-2 virus, especially via aerosol but further studies with larger sample size and longer follow-up periods are required to investigate this relationship.

Lesson learned from COVID-19 pandemic for the future of food industry

With WHO announcing COVID-19 no longer as a public health emergency of international concern (PHEIC) on May 5, 2023, coupled with the fact that the majority of the countries of the world have dropped strict city lockdown or border closure, this perhaps signals the end of the COVID-19 crisis caused by the SARS-CoV-2 virus. However, the COVID-19 pandemic has resulted in far-reaching effects affecting nearly every aspect of our lives and society. Notably, the food industry including agriculture, food manufacturers, food logistics, distributors and retailers have all felt the profound impact and had experienced significant stress during the pandemic. Therefore, it is essential to retrospect the lessons that can be learned from this pandemic for the food industry. This short review aims to address the food safety issues related to the COVID-19 pandemic by focusing on its foodborne transmission potential, innovations of virus detection strategies suitable for food industry; development of phathogenicaidal methods and devices to inactivate SARS-CoV-2 virus (particularly in industrial scale); and the set-up of related food regulations and guidelines as preventive and control measures for preventing the spread of SARS-CoV-2 virus through the food supply chain during the pandemic. This article may provide useful references for the food industry to minimize the food safety impact of COVID-19 (as well as other respiratory virus) and allows them to better prepare for similar future challenges.

Efficacy of mouthwash on reducing salivary SARS-CoV-2 viral load and clinical symptoms: a systematic review and meta-analysis

BACKGROUND

COVID-19 has been a public health emergency of international concern (PHEIC) for a lengthy period of time. The novel coronavirus is primarily spread via aerosols at a short distance, with infected individuals releasing large amounts of aerosols when speaking and coughing. However, there is an open question regarding whether mouthwash could effectively reduce virus transmission during the COVID-19 pandemic and support the prevention of infection among medical workers.

METHODS

Cochrane Library, PubMed, Web of Science, and Embase databases were systematically searched from the inception of each database to January 12, 2023 for currently available randomized clinical trials (RCTs) on the effect of mouthwash on novel coronavirus load in the oral cavity in COVID-19 patients. The treatment group received mouthwash for rinsing the mouth, while the control group received a placebo or distilled water for COVID-19 patients. The primary outcomes were CT value and viral load. Odds ratios (ORs) were estimated using a random-effects model. Subgroup and sensitivity analyses were performed to minimize the bias and the impact of heterogeneity.

RESULTS

Thirteen RCTs were included. Seven studies reported the intervention effect of mouthwash on the CT value of novel coronavirus. The analysis results showed that the mouthwash group had a positive impact on the CT value of novel coronavirus [ SMD = 0.35, 95% CI (0.21, 0.50)] compared with the control group. In addition, subgroup analysis showed a significant positive effect of mouthwash on CT values in the treatment group compared with the control group, with chlorhexidine (CHX) [SMD = 0.33, 95% CI (0.10, 0.56)], povidone-iodine (PVP-I) [SMD = 0.61, 95% CI (0.23, 0.99)], or hydrogen peroxide (HP) [SMD = 1.04, 95% CI (0.30, 1.78)] as an ingredient of the mouthwash. Six studies reported the intervention effect of mouthwash on the viral load, 263 cases in the treatment group and 164 cases in the control group. The analysis results showed that there was no statistical difference between the mouthwash group and the control group in the viral load of novel coronavirus [SMD = -0.06, 95% CI (-0.18, 0.05)]. In the subgroup analysis by measurement time, there were statistically significant differences between the mouthwash and control groups for CT values [SMD = 0.52, 95% CI (0.31, 0.72)] and viral load [SMD =  - 0.32, 95% CI (- 0.56, - 0.07)] within 30 min of gargling.

CONCLUSIONS

In summary, mouthwash has some efficacy in reducing the viral load of novel coronavirus, especially within 30 min after rinsing the mouth. Mouthwash containing CHX, PVP-I and HP all had significant positive effects on CT values, and PVP-I-containing mouthwash may be a promising option to control novel coronavirus infections and relieve virus-related symptoms. However, studies on the dose and frequency of use of mouthwash for infection control are still lacking, which may limit the clinical application of mouthwash.

TRIAL REGISTRATION

Protocol registration: The protocol was registered at PROSPERO (CRD42023401961).

Plant Cell-Engineered Gold Nanoparticles Conjugated to Quercetin Inhibit SARS-CoV-2 and HSV-1 Entry

Recent studies have revealed considerable promise in the antiviral properties of metal nanomaterials, specifically when biologically prepared. This study demonstrates for the first time the antiviral roles of the plant cell-engineered gold nanoparticles (pAuNPs) alone and when conjugated with quercetin (pAuNPsQ). We show here that the quercetin conjugated nanoparticles (pAuNPsQ) preferentially inhibit the cell entry of two medically important viruses-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and herpes simplex virus type-1 (HSV-1) using different mechanisms. Interestingly, in the case of SARS-CoV-2, the pre-treatment of target cells with pAuNPsQ inhibited the viral entry, but the pre-treatment of the virus with pAuNPsQ did not affect viral entry into the host cell. In contrast, pAuNPsQ demonstrated effective blocking capabilities against HSV-1 entry, either during the pre-treatment of target cells or by inducing virus neutralization. In addition, pAuNPsQ also significantly affected HSV-1 replication, evidenced by the plaque-counting assay. In this study, we also tested the chemically synthesized gold nanoparticles (cAuNPs) of identical size and shape and observed comparable effects. The versatility of plant cell-based nanomaterial fabrication and its modification with bioactive compounds opens a new frontier in therapeutics, specifically in designing novel antiviral formulations.

Persistence of Coronavirus on Surface Materials and Its Control Measures Using Nonthermal Plasma and Other Agents

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has been responsible for the initiation of the global pandemic since 2020. The virus spreads through contaminated air particles, fomite, and surface-contaminated porous (i.e., paper, wood, and masks) and non-porous (i.e., plastic, stainless steel, and glass) materials. The persistence of viruses on materials depends on porosity, adsorption, evaporation, isoelectric point, and environmental conditions, such as temperature, pH, and relative humidity. Disinfection techniques are crucial for preventing viral contamination on animated and inanimate surfaces. Currently, there are few effective methodologies for preventing SARS-CoV-2 and other coronaviruses without any side effects. Before infection can occur, measures must be taken to prevent the persistence of the coronavirus on the surfaces of both porous and non-porous inanimate materials. This review focuses on coronavirus persistence in surface materials (inanimate) and control measures. Viruses are inactivated through chemical and physical methods; the chemical methods particularly include alcohol, chlorine, and peroxide, whereas temperature, pH, humidity, ultraviolet irradiation (UV), gamma radiation, X-rays, ozone, and non-thermal, plasma-generated reactive oxygen and nitrogen species (RONS) are physical methods.

Development of a novel, entirely herbal-based mouthwash effective against common oral bacteria and SARS-CoV-2

BACKGROUND

Parallel to the growth of the oral healthcare market, there is a constantly increasing demand for natural products as well. Many customers prefer products that contain fewer toxic agents, therefore providing an environmentally friendly solution with the benefit of smaller risk to the user. Medieval and early modern medicinal knowledge might be useful when looking for natural, herbal-based components to develop modern products. Along with these considerations we created, tested, and compared an entirely natural mouthwash, named Herba Dei.

METHODS

The manufacturing procedure was standardized, and the created tincture was evaluated by GC/MS analysis for active compounds, experimentally tested in cell-based cytotoxicity, salivary protein integrity, cell-free antioxidant activity, anti-bacterial and anti-viral assays, and compared with three market-leading mouthwashes.

RESULTS

Our tincture did not show significant damage in the cytotoxicity assays to keratinocyte and Vero E6 cells and did not disrupt the low molecular weight salivary proteins. Its radical scavenging capacity surpassed that of two tested, partly natural, and synthetic mouthwashes, while its antibacterial activity was comparable to the tested products, or higher in the bacterial aerobic respiratory assay. The active compounds responsible for the effects include naturally occurring phenylpropanoids, terpenes, and terpenoids. Our mouthwash proved to be effective in vitro in lowering the copy number of SARS-CoV-2 in circumstances mimicking the salivary environment.

CONCLUSIONS

The developed product might be a useful tool to impede the transmission and spread of SARS-CoV-2 in interpersonal contact and aerosol-generating conditions. Our mouthwash can help reduce the oral bacterial flora and has an antioxidant activity that facilitates wound healing and prevents adverse effects of smoke in the oral cavity.

Preprocedural mouthwashes for infection control in dentistry-an update

OBJECTIVES

Aerosols and splatter are routinely generated in dental practice and can be contaminated by potentially harmful bacteria or viruses such as SARS-CoV-2. Therefore, preprocedural mouthwashes containing antiseptic agents have been proposed as a potential measure for infection control in dental practice. This review article aims to summarize the clinical (and, if insufficient, preclinical) evidence on preprocedural mouthwashes containing antiseptic agents and to draw conclusions for dental practitioners.

METHODS

Literature on preprocedural mouthwashes for reduction of bacterial or viral load in dental aerosols was searched and summarized.

RESULTS

Preprocedural mouthwashes, particularly those containing chlorhexidine digluconate (CHX), cetylpyridinium chloride (CPC), or essential oils (EO), can significantly reduce the bacterial load in dental aerosols. With respect to viruses such as HSV-1, there are too little clinical data to draw any clear recommendations. On the other hand, clinical data is consolidating that CPC-containing mouthwashes can temporarily reduce the intraoral viral load and infectivity in SARS-CoV-2 positive individuals. Nevertheless, potential risks and side effects due to regular antiseptic use such as ecological effects or adaptation of bacteria need to be considered.

CONCLUSIONS

The use of preprocedural mouthwashes containing antiseptics can be recommended according to currently available data, but further studies are needed, particularly on the effects on other viruses besides SARS-CoV-2. When selecting a specific antiseptic, the biggest data basis currently exists for CHX, CPC, EO, or combinations thereof.

CLINICAL RELEVANCE

Preprocedural mouthwashes containing antiseptics can serve as part of a bundle of measures for protection of dental personnel despite some remaining ambiguities and in view of potential risks and side effects.

Inactivation of SARS-CoV-2 and Other Enveloped and Non-Enveloped Viruses with Non-Thermal Plasma for Hospital Disinfection

As recently highlighted by the SARS-CoV-2 pandemic, viruses have become an increasing burden for health, global economy, and environment. The control of transmission by contact with contaminated materials represents a major challenge, particularly in hospital environments. However, the current disinfection methods in hospital settings suffer from numerous drawbacks. As a result, several medical supplies that cannot be properly disinfected are not reused, leading to severe shortages and increasing amounts of waste, thus prompting the search for alternative solutions. In this work, we report that non-thermal plasma (NTP) can effectively inactivate SARS-CoV-2 from non-porous and porous materials commonly found in healthcare facilities. We demonstrated that 5 min treatment with a dielectric barrier discharge NTP can inactivate 100% of SARS-CoV-2 (Wuhan and Omicron strains) from plastic material. Using porcine respiratory coronavirus (surrogate for SARS-CoV-2) and coxsackievirus B3 (highly resistant non-enveloped virus), we tested the NTP virucidal activity on hospital materials and obtained complete inactivation after 5 and 10 min, respectively. We hypothesize that the produced reactive species and local acidification contribute to the overall virucidal effect of NTP. Our results demonstrate the potential of dielectric barrier discharge NTPs for the rapid, efficient, and low-cost disinfection of healthcare materials.

Efficacy of a Mouthwash Containing CHX and CPC in SARS-CoV-2-Positive Patients: A Randomized Controlled Clinical Trial

Soon after the outbreak of the coronavirus disease 2019 (COVID-19) pandemic, preprocedural mouthwashes were recommended for temporarily reducing intraoral viral load and infectivity of individuals potentially infected with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in order to protect medical personnel. Particularly, the antiseptic cetylpyridinium chloride (CPC) has shown virucidal effects against SARS-CoV-2 in vitro. Therefore, the aim of this randomized controlled clinical trial was to investigate the efficacy of a commercially available mouthwash containing CPC and chlorhexidine digluconate (CHX) at 0.05% each in SARS-CoV-2-positive patients as compared to a placebo mouthwash. Sixty-one patients who tested positive for SARS-CoV-2 with onset of symptoms within the last 72 h were included in this study. Oropharyngeal specimens were taken at baseline, whereupon patients had to gargle mouth and throat with 20 mL test or placebo (0.9% NaCl) mouthwash for 60 s. After 30 min, further oropharyngeal specimens were collected. Viral load was analyzed by quantitative reverse transcriptase polymerase chain reaction, and infectivity of oropharyngeal specimens was analyzed by virus rescue in cell culture and quantified via determination of tissue culture infectious doses 50% (TCID₅₀). Data were analyzed nonparametrically (α = 0.05). Viral load slightly but significantly decreased upon gargling in the test group (P = 0.0435) but not in the placebo group. Viral infectivity as measured by TCID₅₀ also significantly decreased in the test group (P = 0.0313), whereas there was no significant effect but a trend in the placebo group. Furthermore, it was found that the specimens from patients with a vaccine booster exhibited significantly lower infectivity at baseline as compared to those without vaccine booster (P = 0.0231). This study indicates that a preprocedural mouthwash containing CPC and CHX could slightly but significantly reduce the viral load and infectivity in SARS-CoV-2-positive patients. Further studies are needed to corroborate these results and investigate whether the observed reductions in viral load and infectivity could translate into clinically useful effects in reducing COVID-19 transmission (German Clinical Trials Register DRKS00027812).

Effect of Anti-COVID-19 Mouthwashes on Shear Bond Strength of Resin-Matrix Ceramics Repaired with Resin Composite Using Universal Adhesive: An In Vitro Study

Using anti-COVID-19 mouthwashes has become necessary to reduce acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transmissions. Resin-matrix ceramic (RMCs) materials that are exposed to mouthwashes may affect the bonding of repaired materials. This research was performed to assess the effects of anti-COVID-19 mouthwashes on the shear bond strengths (SBS) of RMCs repaired with resin composites. A total of 189 rectangular specimens of two different RMCs (Vita Enamic (VE) and Shofu Block HC (ShB)) were thermocycled and randomly divided into nine subgroups according to different mouthwashes (distilled water (DW), 0.2% povidone–iodine (PVP-I), and 1.5% hydrogen peroxide (HP)) and surface treatment protocols (no surface treatment, hydrofluoric acid etching (HF), and sandblasting (SB)). A repair protocol for RMCs was performed (using universal adhesives and resin composites), and the specimens were assessed using an SBS test. The failure mode was examined using a stereomicroscope. The SBS data were evaluated using a three-way ANOVA and a Tukey post hoc test. The SBS were significantly affected by the RMCs, mouthwashes, and surface treatment protocols. Both surface treatment protocols (HF and SB) for both RMCs, whether immersed in anti-COVID-19 mouthwash or not, improved the SBS. For the VE immersed in HP and PVP-I, the HF surface treatment had the highest SBS. For the ShB immersed in HP and PVP-I, the SB surface treatment had the highest SBS.

Utility of mouth rinses with povidone-iodine and hydrogen peroxide in patients with COVID-19

INTRODUCTION

Povidone-iodine and hydrogen peroxide could be effective in against SARS-CoV-2.

METHODS

A "non-interventional trial" in 88 patients (43±17 yrs., 55% men) with SARS-CoV-2 in nasopharyngeal swabs (RT-PCR). 31 received mouth rinses/gargling with povidone-iodine (every 8h, two consecutive days), 17 with mouth rinses/gargling of hydrogen peroxide, and 40 controls. Were repeated PCR in 3, 11 and 17 days.

RESULTS

After intervention the viral load (Log10 copies/ml) remained similar in povidone-iodine (4.3±2.7 copies/ml), hydrogen peroxide (4.6±2.9 copies/ml; p=0.40) and controls (4.4±3.0 copies/ml). The percentage of patients with a negative result in the second PCR was 27% in povidone-iodine group, 23% in hydrogen peroxide and 32% in controls; in the third PCR, 62%, 54% y 58% respectively; and in the fourth PCR, 81%, 75% y 81%.

CONCLUSION

Our results do not support the clinical usefulness of mouth rinses/gargling with povidone-iodine or hydrogen peroxide in patients with COVID-19.

[Utility of mouth rinses with povidone-iodine and hydrogen peroxide in patients with COVID-19]

Introduction

Povidone-iodine and hydrogen peroxide could be effective in against SARS-CoV-2.

Methods

A "non-interventional trial" in 88 patients (43 ± 17 yrs, 55% men) with SARS-CoV-2 in nasopharyngeal swabs (RT-PCR). 31 received mouth rinses/gargling with povidone-iodine (every 8 h, two consecutive days), 17 with mouth rinses/gargling of hydrogen peroxide, and 40 controls. PCR were repeated at 3, 11 and 17 days.

Results

After intervention the viral load (Log 10 copies/ml) remained similar in povidone-iodine (4.3 ± 2.7 copies/ml), hydrogen peroxide (4.6 ± 2.9 copies/ml; p = 0.40) and controls (4.4 ± 3.0 copies/ml). The percentage of patients with a negative result in the second PCR was 27% in povidone-iodine group, 23% in hydrogen peroxide and 32% in controls; in the third PCR, 62%, 54% and 58% respectively; and in the fourth PCR, 81%, 75% and 81%.

Conclusion

Our results do not support the clinical usefulness of mouth rinses/gargling with povidone-iodine or hydrogen peroxide in patients with COVID-19.

Role of antiseptics in the prevention and treatment of infections in nursing homes

Inadequate infection control, wound care, and oral hygiene protocols in nursing homes pose challenges to residents' quality of life. Based on the outcomes from a focus group meeting and a literature search, this narrative review evaluates the current and potential roles of antiseptics within nursing home infection management procedures. We examine contemporary strategies and concerns within the management of meticillin-resistant Staphylococcus aureus (MRSA; including decolonization regimes), chronic wound care, and oral hygiene, and review the available data for the use of antiseptics, with a focus on povidone-iodine. Compared with chlorhexidine, polyhexanide, and silver, povidone-iodine has a broader spectrum of antimicrobial activity, with rapid and potent activity against MRSA and other microbes found in chronic wounds, including biofilms. As no reports of bacterial resistance or cross-resistance following exposure to povidone-iodine exist, it may be preferable for MRSA decolonization compared with mupirocin and chlorhexidine, which can lead to resistant MRSA strains. Povidone-iodine oral products have greater efficacy against oral pathogens compared with other antiseptics such as chlorhexidine mouthwash, highlighting the clinical benefit of povidone-iodine in oral care. Additionally, povidone-iodine-based products, including mouthwash, have demonstrated rapid in-vitro virucidal activity against SARS-CoV-2 and may help reduce its transmission if incorporated into nursing home coronavirus 2019 control protocols. Importantly, povidone-iodine activity is not adversely affected by organic material, such as that found in chronic wounds and the oral cavity. Povidone-iodine is a promising antiseptic agent for the management of infections in the nursing home setting, including MRSA decolonization procedures, chronic wound management, and oral care.

Mouth rinses efficacy on salivary SARS-CoV-2 viral load: A randomized clinical trial

Considering the global trend to confine the COVID-19 pandemic by applying various preventive health measures, preprocedural mouth rinsing has been proposed to mitigate the transmission risk of SARS-CoV-2 in dental clinics. The study aimed to investigate the effect of different mouth rinses on salivary viral load in COVID-19 patients. This study was a single-center, randomized, double-blind, six-parallel-group, placebo-controlled clinical trial that investigated the effect of four mouth rinses (1% povidone-iodine, 1.5% hydrogen peroxide, 0.075% cetylpyridinium chloride, and 80 ppm hypochlorous acid) on salivary SARS-CoV-2 viral load relative to the distilled water and no-rinse control groups. The viral load was measured by quantitative reverse transcription PCR (RT-qPCR) at baseline and 5, 30, and 60 min post rinsing. The viral load pattern within each mouth rinse group showed a reduction overtime; however, this reduction was only statistically significant in the hydrogen peroxide group. Further, a significant reduction in the viral load was observed between povidone-iodine, hydrogen peroxide, and cetylpyridinium chloride compared to the no-rinse group at 60 min, indicating their late antiviral potential. Interestingly, a similar statistically significant reduction was also observed in the distilled water control group compared to the no-rinse group at 60 min, proposing mechanical washing of the viral particles through the rinsing procedure. Therefore, results suggest using preprocedural mouth rinses, particularly hydrogen peroxide, as a risk-mitigation step before dental procedures, along with strict adherence to other infection control measures.

Comparative efficacy evaluation of disinfectants against severe acute respiratory syndrome coronavirus-2

BACKGROUND

Disinfection is one of the most effective ways to block the rapid transmission of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). Due to the prolonged coronavirus disease 2019 (COVID-19) pandemic, disinfectants have become crucial to prevent person-to-person transmission and decontaminate hands, clothes, facilities and equipment. However, there is a lack of accurate information on the virucidal activity of commercial disinfectants.

AIM

To evaluate the virucidal efficacy of 72 commercially available disinfectants constituting 16 types of ingredients against SARS-CoV-2.

METHODS

SARS-CoV-2 was tested with various concentrations of disinfectants at indicated exposure time points as recommended by the manufacturers. The 50% tissue culture infectious dose assay was used to calculate virus titre, and trypan blue staining and CCK-8 were used to assess cell viability after 3-5 days of SARS-CoV-2 infection.

FINDINGS

This study found that disinfectants based on 83% ethanol, 60% propanol/ethanol, 0.00108-0.0011% sodium dichloroisocyanurate and 0.497% potassium peroxymonosulfate inactivated SARS-CoV-2 effectively and safely. Although disinfectants based on 0.05-0.4% benzalkonium chloride (BAC), 0.02-0.07% quaternary ammonium compound (QAC; 1:1), 0.4% BAC/didecyldimethylammonium chloride (DDAC), 0.28% benzethonium chloride concentrate/2-propanol, 0.0205-0.14% DDAC/polyhexamethylene biguanide hydrochloride (PHMB) and 0.5% hydrogen peroxide inactivated SARS-CoV-2 effectively, they exhibited cytotoxicity. Conversely, disinfectants based on 0.04-4% QAC (2:3), 0.00625% BAC/DDAC/PHMB, and 0.0205-0.14% and 0.0173% peracetic acid showed approximately 50% virucidal efficacy with no cytotoxicity. Citric acid (0.4%) did not inactivate SARS-CoV-2.

CONCLUSION

These results indicate that most commercially available disinfectants exert a disinfectant effect against SARS-CoV-2. However, re-evaluation of the effective concentration and exposure time of certain disinfectants is needed, especially citric acid and peracetic acid.

Efficacy of mouthrinses in reducing oral SARS-COV-2 load: a review

Accumulated evidence has shown that the oral cavity may be an important reservoir for SARS-CoV-2. Some authors have suggested that the use of mouthrinses could reduce SARS-CoV-2 viral load in the saliva. Thus, the aim of this review was to synthesize evidence about the efficacy of mouthrinses in reducing the salivary viral load of SARS-CoV-2. 2. Nine randomized controlled trials (RCTs) have investigated the efficacy of different mouthrinses in reducing salivary SARS-CoV-2 loads. Various active ingredients have been tested in these trials: 0.5%,1% and 2% povidone-iodine, 0.2% and 0.12% chlorhexidine (CHX), 0.075% cetylpyridinium chloride (CPC), 0.075% CPC with Zinc lactate, 1% and 1.5% hydrogen peroxide (HP), 1.5% HP + 0.12% CHX and ß-cyclodextrin and citrox. The studies reported an intra-group reduction in the salivary levels of the virus, when compared with the baseline. However, the majority of these trials failed to demonstrate a significant inter-group difference between active groups and the control group relative to the decrease in salivary SARS-CoV-2 loads. Although promising, these results should be confirmed by larger trials.

Efectividad de enjuagues bucales contra virus de la familia coronavirus

La aparición del virus Sars-CoV-2 y la enfermedad Covid-19 han provocado un estado de emergencia en el sistema de salud. Teniendo en cuenta el potencial de la saliva como material contaminante, la práctica odontológica fue una de las áreas que se vio afectada debido al uso de instrumentos que pueden esparcir aerosoles y salpicaduras que contienen microorganismos hacia el medio ambiente. Por esta razón, conociendo su potencial en la inactivación de patógenos, se propuso la utilización de enjuagues bucales en la práctica clínica previo a la realización de procedimientos dentales, sin embargo la evidencia no es clara respecto a su efectividad. Objetivo. Establecer el estado de evidencia actual del efecto de los enjuagues bucales sobre los coronavirus que se encuentran en cavidad. Métodos. Se realizó una revisión sistemática siguiendo todos los parámetros descritos en las DirectricesPRISMA basada en información obtenida en los buscadores Science direct, Pubmed y Dentistry and Oral Science Source. Los criterios de selección incluyeron estudios in vivo e in vitro de texto completo que evidenciaron la efectividad del enjuague bucal contra coronavirus. Resultados. Se obtuvieron 90 artículos, de los cuales sólo 12 cumplían con los criterios de inclusión,8 in vitro y 4 in vivo, que fueron sometidos a la evaluación de calidad metodológica utilizando la lista de verificación de evaluación crítica del JBI.  Conclusiones. Los resultados sugieren que la povidona yodada es efectiva para la inactivación del virus Sars-coV-2 en todas sus concentraciones.

Repurposing povidone-iodine to reduce the risk of SARS-CoV-2 infection and transmission: a narrative review

BACKGROUND

Accumulating data suggest antiviral effects of povidone-iodine against the Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus. This narrative review aims to examine the antiviral mechanisms of povidone-iodine, efficacy of povidone-iodine against the SARS-CoV-2 virus, and safety of povidone-iodine to human epithelial cells and thyroid function.

METHODS

We searched the electronic databases PubMed, Embase, Cochrane Library, ClinicalTrials.gov and World Health Organization's International Clinical Trials Registry Platform for articles containing the keywords "povidone-iodine", "SARS-CoV-2" and "COVID-19" from database inception till 3 June 2021.

RESULTS

Despite in vitro data supporting the anti-SARS-CoV-2 effects of povidone-iodine, findings from clinical studies revealed differences in treatment response depending on study settings (healthy vs. hospitalized individuals), treatment target (nasal vs. oral vs. pharynx), method of administration (oral rinse vs. gargle vs. throat spray) and choice of samples used to measure study endpoints (nasopharyngeal vs. saliva). One large-scale clinical trial demonstrated reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak. Povidone-iodine is also used to disinfect the oro-pharyngeal space prior to dental or otolaryngology procedures. Although existing data suggest minimal impact of povidone-iodine on thyroid function, high-quality safety data are presently lacking.

CONCLUSIONS

Povidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.Key messagesAccumulating data suggest antiviral effects of povidone-iodine against the SARS-CoV-2 virus.Findings from clinical studies reveal differences in treatment response depending on study settings, treatment target, method of administration and choice of samples used to measure study endpoints. One large-scale clinical trial observed reduction in the incidence of SARS-CoV-2 infection among participants who administered povidone-iodine 3 times daily during an active outbreak.Povidone-iodine application to the oropharyngeal space could complement existing non-pharmacological interventions to reduce SARS-CoV-2 infection especially in high exposure settings.

Stable thyroid function despite regular use of povidone-iodine throat spray for SARS-CoV-2 prophylaxis

BACKGROUND

It is unclear whether unintentional ingestion of povidone-iodine following its application to the oropharyngeal space could affect thyroid function.

OBJECTIVE

To examine thyroid function among individuals who regularly apply povidone-iodine throat spray for SARS-CoV-2 prophylaxis.

METHODS

We designed a case-control study to compare thyroid function among participants who received povidone-iodine throat spray three times a day for 42 days ('cases') and those who received vitamin C ('controls'). Thyroid function was assessed by profiling serum TSH, free T3, and free T4; iodine status was estimated using serum thyroglobulin level, while infection status was determined by measuring anti-SARS-CoV-2 antibody against the nucleocapsid antigen. All measurements were performed in pairs, at baseline and 42 days later. Pre-post changes in thyroid function were compared between groups, before and after stratification according to baseline TSH quartiles.

RESULTS

A total of 177 men (117 cases and 60 controls) (mean age, 32.2 years) were included. Despite comparable demographics and clinical profiles, no clinically or statistically significant differences were observed in thyroid indices between 'cases' and 'controls' before and after stratification according to TSH quartiles. None of the participants developed symptomatic hypo- or hyperthyroidism throughout the study. Post-hoc analysis did not reveal differences in thyroid function according to infection status.

CONCLUSIONS

Data from this study support the overall safety of povidone-iodine use in the oropharyngeal space for SARS-CoV-2 prophylaxis among individuals with normal thyroid function and subclinical thyroid disease.

Virucidal activity in vitro of mouthwashes against a feline coronavirus type II

Transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can occur through saliva and aerosol droplets deriving from the upper aerodigestive tract during coughing, sneezing, talking, and even during oral inspection or dental procedures. The aim of this study was to assess in vitro virucidal activity of commercial and experimental mouthwashes against a feline coronavirus (FCoV) strain. Commercial and experimental (commercial-based products with addition of either sodium dodecyl sulfate (SDS) or thymus vulgaris essential oil (TEO) at different concentrations) mouthwashes were placed in contact with FCoV for different time intervals, that is, 30 s (T30), 60 s (T60), and 180 s (T180); subsequently, the virus was titrated on Crandell Reese Feline Kidney cells. An SDS-based commercial mouthwash reduced the viral load by 5 log10 tissue culture infectious dose (TCID)₅₀ /50 µl at T30 while a cetylpyridinium (CPC)-based commercial mouthwash was able to reduce the viral titer of 4.75 log10 at T60. Furthermore, five experimental mouthwashes supplemented with SDS reduced the viral titer by 4.75-5 log10 according to a dose- (up to 4 mM) and time-dependent fashion.

Evaluation of Current Evidence on the Use of Oral Antiseptics Against SARS-CoV-2: A Narrative Review

AIMS AND OBJECTIVES

The detection of SARS-COV-2 in the oral cavity has generated endless claims about the efficacy of using oral mouthwashes to reduce viral load. This review aims to assess the current evidence on the use of oral antiseptics against SARS-CoV-2 and to assess the certainty of the evidence according to the GRADE system. The question this study focussed on was what is the efficacy of oral antiseptics against SARS-CoV-2?

MATERIALS AND METHODS

A bibliographic search was performed in Medline databases through PubMed, Science Direct, and Google Scholar (until February 2022), using search terms related to COVID-19 and oral antiseptics. Two independent researchers extracted the information from the articles included in an excel form. The identification and selection of the studies was carried out from August 2021 to February 2022.

RESULTS

It was found that oral antiseptics can have a potential beneficial effect on COVID-19, mainly in reducing viral load. However, these potential benefits are mainly based on in-vitro studies or clinical studies with various methodological limitations. At present, the certainty of the evidence is very low due to inconsistency (heterogeneity), moderate-to-high risk of bias, and imprecision of the results.

CONCLUSION

The certainty of the current evidence on the efficacy of oral antiseptics against SARS-CoV-2 is very low, mainly due to the methodological limitations of the studies. Therefore, for evidence-based decision-making about this intervention, clinical studies with greater methodological rigor are required. Oral antiseptics could present potential benefits in patients with COVID-19 mainly by reducing viral load. However, a careful and conscious evaluation of the evidence is required for decision-making in clinical practice.

Lignin: A Sustainable Antiviral Coating Material

Transmission of viruses through contact with contaminated surfaces is an important pathway for the spread of infections. Antiviral surface coatings are useful to minimize such risks. Current state-of-the-art approaches toward antiviral surface coatings either involve metal-based materials or complex synthetic polymers. These approaches, however, even if successful, will have to face great challenges when it comes to large-scale applications and their environmental sustainability. Here, an antiviral surface coating was prepared by spin-coating lignin, a natural biomass residue of the paper production industry. We show effective inactivation of herpes simplex virus type 2 (>99% after 30 min) on a surface coating that is low-cost and environmentally sustainable. The antiviral mechanism of the lignin surface was investigated and is attributed to reactive oxygen species generated upon oxidation of lignin phenols. This mechanism does not consume the surface coating (as opposed to the release of a specific antiviral agent) and does not require regeneration. The coating is stable in ambient conditions, as demonstrated in a 6 month aging study that did not reveal any decrease in antiviral activity. This research suggests that natural compounds may be used for the development of affordable and sustainable antiviral coatings.

Effect of Mouthwashes for COVID-19 Prevention on Surface Changes of Resin Composites

OBJECTIVE

The aim of this research was to investigate the effect of various mouthwashes for COVID-19 prevention on surface hardness, roughness, and colour changes of bulk-fill and conventional resin composites and determine the pH and titratable acidity of mouthwashes.

METHODS

Four hundred eighty specimens were fabricated in cylindrical moulds (10 mm in diameter and 2 mm in thickness). Before immersion, baseline data of surface hardness, roughness, and colour values were recorded. Each product of specimens (Filtek Z350XT, Premise, Filtek One Bulk Fill Restorative, SonicFil 2) were divided into 4 groups for 0.2% povidone iodine, 1% hydrogen peroxide, 0.12% chlorhexidine, and deionised water (serving as a control). The specimens were immersed in mouthwashes for 1 minute and then stored in artificial saliva until 24 hours. This process was repeated for 14 days. After immersion, surface hardness, roughness, and colour values of specimens were measured at 7 and 14 days. The data were statistically analysed by 2-way repeated analysis of variance, Tukey honestly significant difference, and t test (P < .05).

RESULTS

After immersion, all mouthwashes caused significantly lower surface hardness and greater roughness and colour values (P < .05) on all resin composites tested.

CONCLUSIONS

Mouthwashes had an effect on all resin composites evaluated leading to a significant decreased surface hardness and an increased roughness and colour values (P < .05).

Yogic Neti-Kriya Using Povidone Iodine: Can it have a Preventive Role Against SARS-CoV-2 Infection Gateway?

During this COVID-19 pandemic, except steroid, none of the therapeutic measures have showed any evidence of efficacy. Traditionally jala-neti using lukewarm salted water remains a yogic way of maintaining upper airway hygiene. Saline irrigation decreases the concentration of inflammatory mediators (e.g. histamine, leukotriene etc.) in nasal secretions, reduces the severity and frequency of sinusitis, reduce need of antibiotic therapy and restores competency of nasal mucosa. Jala-neti is an integral part of six cleansing techniques of yogic kriyas practised in India since thousands of years. Jala-neti can clean the upper airways, prevents colonization of infectious agents, removes foreign bodies, prevents stasis of mucous and subsequently enhances the drainage of paranasal sinuses and maintain health. Regular practice of Jala neti improves nasal symptoms and overall health status of patients with sinusitis. Jala-neti sample can even be used for COVID-19 diagnosis. Povidone iodine (PVP-I) has been utilized as a time tested antimicrobial agent with broad spectrum coverage against wide range of bacteria and viruses. Anti-SARS-CoV-2 action of PVP-I was seen at a concentration as low as 0.45%. PVP-I is generally well tolerated upto 5%, however nasal ciliotoxicity is reported at this concentration, however, this toxicity is not reported with lower concentrations(1.25% and 0.5%). So, theoretically, by using neti-kriya with povidone iodine (0.5-1%) as irrigation solution can combine and enhance the protection against COVID-19 and this can be an important armor in the fight against COVID-19. However, this hypothesis needs to be validated in real life clinical trial scenario before implementing.

Efficacy of Mouth Rinses and Nasal Spray in the Inactivation of SARS-CoV-2: A Systematic Review and Meta-Analysis of In Vitro and In Vivo Studies

Severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) is a global and evolving pandemic associated with heavy health and financial burdens. Considering the oral cavity as the major reservoir for SARS-CoV-2, a systematic review and meta-analysis were conducted to assess the efficacy of mouth rinses and nasal sprays in reducing the salivary viral load of SARS-CoV-2. All in vivo and in vitro studies that assessed the virucidal efficacy of mouth rinses and nasal sprays against SARS-CoV-2 and were published in the English language from December 2019 to April 2022 were considered for analyses. Special Medical Subject Headings terms were used to search Pubmed, Scopus, Embase Ovid, and Web of Science databases. The toxicological data reliability assessment tool (ToxRToool) was used to assess the quality of the included studies. Thirty-three studies (11 in vivo and 22 in vitro) were deemed eligible for inclusion in this analysis. Results of the pooled data showed that povidone-iodine is the most efficacious intervention in vivo in terms of reducing the SARS-CoV-2 salivary viral load, followed by chlorhexidine. The mean difference in the viral load was 86% and 72%, respectively. Similarly, povidone-iodine was associated with the highest log₁₀ reduction value (LRV) in vitro, followed by cetylpyridinium chloride, (LRV = 2.938 (p < 0.0005) and LRV = 2.907 (p = 0.009), respectively). Povidone-iodine-based oral and nasal preparations showed favourable results in terms of reducing SARS-CoV-2 viral loads both in vivo and in vitro. Considering the limited number of patients in vivo, further studies among larger cohorts are recommended.

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.

Evaluation of surface disinfection methods to inactivate the beta coronavirus Murine Hepatitis Virus

The list of EPA-approved disinfectants for coronavirus features many products for use on hard, non-porous materials. There are significantly fewer products registered for use on porous materials. Further, many common, high-touch surfaces fall in between non-porous materials such as glass and porous materials such as soft fabrics. The objective of this study was to assess the efficacy of selected commercially available disinfectant products against coronaviruses on common, high-touch surfaces. Four disinfectants (Clorox Total 360, Bleach solution, Vital Oxide, and Peroxide Multi-Surface Cleaner) were evaluated against Murine Hepatitis Virus A59 (MHV) as a surrogate coronavirus for SARS-CoV-2. MHV in cell culture medium was inoculated onto four materials: stainless steel, latex-painted drywall tape, Styrene Butadiene rubber (rubber), and bus seat fabric. Immediately (T0) or 2-hr (T2) post-inoculation, disinfectants were applied by trigger-pull or electrostatic sprayer and either held for recommended contact times (Spray only) or immediately wiped (Spray and Wipe). Recovered infectious MHV was quantified by median tissue culture infectious dose assay. Bleach solution, Clorox Total 360, and Vital Oxide were all effective (>3-log₁₀ reduction or complete kill of infectious virus) with both the Spray Only and Spray and Wipe methods on stainless steel, rubber, and painted drywall tape when used at recommended contact times at both T0 and T2 hr. Multi-Surface Cleaner unexpectedly showed limited efficacy against MHV on stainless steel within the recommended contact time; however, it showed increased (2.3 times greater efficacy) when used in the Spray and Wipe method compared to Spray Only. The only products to achieve a 3-log₁₀ reduction on fabric were Vital Oxide and Clorox Total 360; however, the efficacy of Vital Oxide against MHV on fabric was reduced to below 3-log₁₀ when applied by an electrostatic sprayer compared to a trigger-pull sprayer. This study highlights the importance of considering the material, product, and application method when developing a disinfection strategy for coronaviruses on high-touch surfaces.

Significance of chlorine-dioxide-based oral rinses in preventing SARS-CoV-2 cell entry

OBJECTIVE

This work aims to determine the efficacy of preprocedural oral rinsing with chlorine dioxide solutions to minimize the risk of coronavirus disease 2019 (COVID-19) transmission during high-risk dental procedures.

METHODS

The antiviral activity of chlorine-dioxide-based oral rinse (OR) solutions was tested by pre-incubating with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pseudovirus in a dosage-dependent manner before transducing to human embryonic kidney epithelial (HEK293T-ACE2) cells, which stably expresses ACE-2 receptor. Viral entry was determined by measuring luciferase activity using a luminescence microplate reader. In the cell-to-cell fusion assay, effector Chinese hamster ovary (CHO-K1) cells co-expressing spike glycoprotein of SARS-CoV-2 and T7 RNA polymerase were pre-incubated with the ORs before co-culturing with the target CHO-K1 cells co-expressing human ACE2 receptor and luciferase gene. The luciferase signal was quantified 24 h after mixing the cells. Surface expression of SARS-CoV-2 spike glycoprotein and ACE-2 receptor was confirmed using direct fluorescent imaging and quantitative cell-ELISA. Finally, dosage-dependent cytotoxic effects of ORs were evaluated at two different time points.

RESULTS

A dosage-dependent antiviral effect of the ORs was observed against SARS-CoV-2 cell entry and spike glycoprotein mediated cell-to-cell fusion. This demonstrates that ORs can be useful as a preprocedural step to reduce viral infectivity.

CONCLUSIONS

Chlorine-dioxide-based ORs have a potential benefit for reducing SARS-CoV-2 entry and spread.

Oral Antiseptics against SARS-CoV-2: A Literature Review

Dentists are health care workers with the highest risk of exposure to COVID-19, because the oral cavity is considered to be a reservoir for SARS-CoV-2 transmission. The identification of SARS-CoV-2 in saliva, the generation of aerosols, and the proximity to patients during dental procedures are conditions that have led to these health care workers implementing additional disinfection strategies for their protection. Oral antiseptics are widely used chemical substances due to their ability to reduce the number of microorganisms. Although there is still no evidence that they can prevent the transmission of SARS-CoV-2, some preoperative oral antiseptics have been recommended as control measures, by different health institutions worldwide, to reduce the number of microorganisms in aerosols and droplets during dental procedures. Therefore, this review presents the current recommendations for the use of oral antiseptics against SARS-CoV-2 and analyzes the different oral antiseptic options used in dentistry.

Efficacy of antiseptic mouthrinses against SARS-CoV-2: A prospective randomized placebo-controlled pilot study

Objectives

Methods

Results

Conclusions

Clinical relevance

The Effect of Hydrogen Peroxide and Povidone-Iodine on the Shear Bond Strength of Orthodontic Brackets: An In Vitro Study

BACKGROUND: Chlorhexidine, which is the gold-standard antimicrobial mouthwash, cannot effectively decrease the count of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the causative agent for coronavirus disease-2019 (COVID-19). Since SARS-CoV-2 is susceptible to oxidation, mouthwashes containing oxidizing agents such as hydrogen peroxide (H2O2) or Povidone-iodine (PVP-I) are recommended to decrease the viral count. AIM: This study aimed to assess the effects of H2O2 and PVP-I mouthwashes on the shear bond strength (SBS) of metal orthodontic brackets to the enamel. MATERIALS AND METHODS: This in vitro experimental study evaluated 45 freshly extracted maxillary premolars. The teeth were cleaned and randomized into three groups (n = 15) for rinsing with distilled water (control group), 1% PVP-I (betadine), and 1.5% H2O2 for 60 s. All teeth were etched with 37% phosphoric acid gel, and metal orthodontic brackets were bonded to the teeth using the Transbond XT bonding system. The teeth were mounted in auto-polymerized acrylic resin and incubated in water at 37°C for 72 h. The teeth were then thermocycled for 48 h, and their SBS was measured in a universal testing machine. The adhesive remnant index (ARI) score was also calculated. The groups were compared by ANOVA and Chi-square Monte Carlo test. RESULTS: No significant difference was noted among the three groups in SBS (p = 0.938) or the ARI score (p = 0.780). CONCLUSION: Use of H2O2 and PVP-I mouthwashes has no adverse effect on SBS or mode of failure of metal orthodontic brackets bonded to enamel.

Mouthrinses against SARS-CoV-2 – high antiviral effectivity by membrane disruption in vitro translates to mild effects in a randomized placebo-controlled clinical trial

The emergence of the Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2) represents an unprecedented threat for the human population, necessitating rapid and effective intervention measures. Given the main infection route by airborne transmission, significant attention has been bestowed upon the use of antiseptic mouthrinses as a way to possibly reduce infectious viral titers. However, clinical evaluations are still sparse. Thus, we evaluated a wide variety of antiseptic agents that can be used as mouthrinses for their antiviral effects in vitro and their respective mode of action. One of the most promising antiseptic agents (benzalkoniumchloride, BAC) was used in a randomized placebo-controlled clinical trial with subsequent analysis of viral loads by RT-qPCR and virus rescue in cell culture. Mechanistic analysis revealed that treatment with BAC and other antiseptic agents efficiently inactivated SARS-CoV-2 in vitro by primarily disrupting the viral envelope, without affecting viral RNA integrity. However, the clinical application only resulted in a mild reduction of viral loads in the oral cavity. These results indicate that gargling with mouthrinses comprising single antiseptic agents may play a minor role towards a potential reduction of transmission rates and thus, these findings are of utmost importance when considering alternative COVID-19 prevention strategies.

Antiviral Activity of Contemporary Contact Lens Care Solutions against Two Human Seasonal Coronavirus Strains

Background: Given that reports have suggested SARS-CoV-2 can be transmitted via conjunctiva, the ability of contact lens (CL) care products to reduce the infectiousness of two seasonal human coronavirus (HCoV) (HCoV-229E and HCoV-OC43) surrogates for SARS-CoV-2 was investigated. Methods: Biotrue and Boston Simplus (Bausch&Lomb), OPTI-FREE Puremoist and Clear Care (Alcon), and cleadew and cleadew GP (Ophtecs) were tested. Their ability to inactivate HCoV was evaluated using contact times of 4 and 6 h as well as 1% and 10% of virus inoculum. Results: Non-oxidative systems (Biotrue, Boston Simplus, and OPTI-FREE) did not exhibit a significant log10 reduction compared to controls for the two viral strains for either incubation time (all p > 0.05) when 10% tests were performed. For the 1% test, while Boston Simplus and OPTI-FREE exhibited a significant log10 reduction of both HCoV-229E (after 6 h) and HCoV-OC43 (after either 4 or 6 h incubation), those products showed less than 1 log10 reduction of the two infectious viruses. Oxidative systems based on hydrogen peroxide or povidone-iodine showed a significant log10 reduction compared with the controls for both HCoV-229E and HCoV-OC43 in all tested conditions (all p < 0.01). Clear Care led to virus inactivation to below the limit of quantification for tests performed with 1% of inoculum after 6 h incubation, while cleadew and cleadew GP led to inactivation of the two viruses to below the limit of quantification in all tested conditions. Conclusion: Oxidative CL disinfection systems showed significant virucidal activity against HCoV-229E and HCoV-OC43, while non-oxidative systems showed minimal ability to inactivate the HCoV species examined.

Efficacy of Pre-Procedural Mouthwashes against SARS-CoV-2: A Systematic Review of Randomized Controlled Trials

The oral mucosa is one of the first sites to be affected by the SARS-CoV-2. For this reason, healthcare providers performing aerosol-generating procedures (AGPs) in the oral cavity are at high risk of infection with COVID-19. The aim of this systematic review is to verify whether there is evidence in the literature describing a decrease in the salivary viral load of SARS-CoV-2 after using different mouthwashes. An electronic search of the MEDLINE database (via PubMed), Web of Science, SCOPUS, and the Cochrane library database was carried out. The criteria used were those described by the PRISMA® Statement. Randomized controlled trial studies that have used mouthwashes as a form of intervention to reduce the viral load in saliva were included. The risk of bias was analyzed using the Joanna Briggs Institute Critical Appraisal Tool. Ultimately, eight articles were included that met the established criteria. Based on the evidence currently available in the literature, PVP-I, CHX and CPC present significant virucidal activity against SARS-CoV-2 in saliva and could be used as pre-procedural mouthwashes to reduce the risk of cross-infection.

[The role of local antiseptics in the prevention of coronavirus infection during endonasal interventions on the lacrimal ducts]

In connection with the pandemic of coronavirus infection, it is urgent to develop measures to prevent the intraoperative spread of coronavirus particles and infection of the operating room staff.

OBJECTIVE

Generalization and analysis of available data concerning local antiseptic therapy for the prevention of coronavirus infection during endonasal interventions on the lacrimal tract.

MATERIAL AND METHODS

The search for literature sources was carried out using MEDLINE search engines and the Russian Science Citation Index for queries with the keywords "COVID-19", "coronavirus infection", "antiseptics", "protocol for otorhinolaryngological operations", "dacryosurgical operations" and similar in various combinations.

RESULTS

It has been shown that during endonasal operations on the lacrimal tract, the number of risk factors for infection increases, since these procedures are aerosol-generating, and contact occurs not only with the nasal mucosa, but also with the lacrimal fluid, in which the coronavirus is also replicated. The data on the effectiveness of various antiseptics are summarized, the analysis of the possibility of their use in preoperative preparation for endonasal interventions on the lacrimal tract from the point of view of efficacy and safety is carried out. Information is provided on the proprietary protocol for the use of antiseptics to prevent the spread of coronavirus infection during endonasal dacryocystorhinostomy. It is shown that the preventive use of local disinfectants reduces the number of viral particles on the nasal mucosa, which leads to a decrease in contamination of the surrounding space. Among the available and studied antiseptics, the most suitable is povidone-iodine, which can be used in concentrations up to 1.25% to irrigate the nasal mucosa before surgery with an exposure of 30-60 sec. When performing operations on the lacrimal pathways, it is also advisable to carry out antiseptic treatment of the conjunctival cavity with a 5% solution of povidone-iodine and rinse the lacrimal pathways before the operation with povidone-iodine in a concentration of 0.4%.

CONCLUSION

To date, information has been obtained that makes it advisable to use antiseptics before performing endonasal aerosol-generating interventions, in particular endonasal dacryocystorhinostomies and recanalization of the tear ducts.

Virucidal Activity of Different Mouthwashes against the Salivary Load of SARS-CoV-2: A Narrative Review

The saliva of COVID-19-confirmed patients presents a high viral load of the virus. Aerosols generated during medical and dental procedures can transport the virus and are a possible causative agent of cross-infection. Since the onset of the pandemic, numerous investigations have been attempting to mitigate the risk of transmission by reducing the viral load in saliva using preprocedural mouthwashes. This study aims to review the most up-to-date in vitro and in vivo studies investigating the efficacy of different mouthwashes on reducing the salivary viral load of SARS-CoV-2, giving particular attention to the most recent randomized control trials published.

How does antiseptic mouthwashes against SARS-COV-2 affect the bond strength of universal adhesive to enamel?

This study compares the effect of different mouthwashes that have been recommended during the Coronavirus disease 2019 (COVID-19) pandemic on shear bond strength (SBS) of universal adhesive to enamel in regards to self-etch (SE) and etch-and-rinse (ER) modes. Flat enamel surfaces were obtained from 100 sound human maxillary central incisors. They were randomly allocated to five groups according to the different mouthwashes (no mouthwash/control [Ctrl], 0.2% chlorhexidine 1.5% hydrogen peroxide [H2 O2 ], 0.2% povidone-iodine [PVP-I], Listerine [L]), and adhesive application modes (ER and SE) (n = 10). After the application of a universal adhesive (single bond universal), composite resin (Filtek Z250) was bonded by a cylinder-shaped mold (height: 2 mm, diameter: 2.4 mm). They were subjected to SBS test using a universal testing machine (AGS-X, Shimadzu Corp.) (crosshead speed: 1 mm/min). The resin-enamel interfaces were observed with a scanning electron microscope (SEM). The semiquantitative chemical microanalyses were performed with energy-dispersive spectroscopy (EDS). The data were statistically analyzed by two-way analysis of variance and Bonferroni test (p < .05). In SE mode, Group Ctrl revealed significantly higher SBS than all mouthwash groups (p < .05). In ER mode, Group Ctrl showed significantly higher SBS than H2 O2 and PVP-I groups (p < .05). ER mode caused significantly higher SBS than SE mode in all mouthwash groups (p < .05). The SEM observations highlighted that Group Ctrl had a regular and intact hybrid layer with resin tag formation while the H2 O2 and PVP-I groups exhibited a thin hybrid layer in both modes. EDS analysis indicated that in SE mode, all mouthwash groups presented increased O content compared to Group Ctrl. H2 O2 and PVP-I that were suggested for preprocedural use during the COVID-19 pandemic, reduced the enamel bond strength of the universal adhesive in ER mode.

Povidone-Iodine as a Pre-Procedural Mouthwash to Reduce the Salivary Viral Load of SARS-CoV-2: A Systematic Review of Randomized Controlled Trials

The use of pre-procedural rinses has been investigated to reduce the number of viral particles and bacteria in aerosols, potentially decreasing the risk of cross-infection from severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during medical and dental procedures. This review aims to confirm whether there is evidence in the literature describing a reduction in salivary load of SARS-CoV-2 when povidone-iodine (PVP-I) is used as a pre-intervention mouthwash. An search of the MEDLINE, Embase, SCOPUS, and the Cochrane library databases was conducted. The criteria used followed the PRISMA® Statement guidelines. Randomized controlled trials investigating the reduction of salivary load of SARS-CoV-2 using PVP-I were included. Ultimately, four articles were included that met the established criteria. According to the current evidence, PVP-I is effective against SARS-CoV-2 in saliva and could be implemented as a rinse before interventions to decrease the risk of cross-infection in healthcare settings.

Is hydrogen peroxide an effective mouthwash for reducing the viral load of SARS-CoV-2 in dental clinics?

BACKGROUND

Previous studies have demonstrated that SARS-CoV-2 is mainly transmitted by inhalation of aerosols and can remain viable in the air for hours. Viruses can spread in dental settings and put professionals and patients at high risk of infection due to proximity and aerosol-generating procedures, and poor air ventilation.

OBJECTIVES

The aim of this study was to investigate the effects of a 1% hydrogen peroxide (H2O2) mouth rinse on reducing the intraoral SARS-CoV-2 load.

METHODS

Portable air cleaners with HEPA filters exposed for 3 months were analysed to test for virus presence in a waiting room (where patients wore a face mask but did not undergo mouth rinsing) and three treatment rooms (where patients wore no mask but carried out mouth rinsing). As CO2 is co-exhaled with aerosols containing SARS-CoV-2 by COVID-19 infected people, we also measured CO2 as a proxy of infection risk indoors. Specific primer and probe RT-PCR were applied to detect viral genomes of the SARS-CoV-2 virus in the filters. Specifically, we amplified the nucleocapsid gene (Nuclv) of SARS-CoV-2.

RESULTS

CO2 levels ranged from 860 to 907 ppm, thus indicating low ventilation and the risk of COVID-19 transmission. However, we only found viral load in filters from the waiting room and not from the treatment rooms. The results revealed the efficiency of 1-minute mouth rinsing with 1% H2O2 since patients rinsed their mouths immediately after removing their mask in the treatment rooms.

CONCLUSIONS

Our findings suggest that dental clinics would be safer and more COVID-19 free by implementing mouth rinsing 1 min with 1% H2O2 immediately after the patients arrive at the clinic.

Advances in the Prophylaxis of Respiratory Infections by the Nasal and the Oromucosal Route: Relevance to the Fight with the SARS-CoV-2 Pandemic

In this time of COVID-19 pandemic, the strategies for prevention of the infection are a primary concern. Looking more globally on the subject and acknowledging the high degree of misuse of protective face masks from the population, we focused this review on alternative pharmaceutical developments eligible for self-defense against respiratory infections. In particular, the attention herein is directed to the nasal and oromucosal formulations intended to boost the local immunity, neutralize or mechanically "trap" the pathogens at the site of entry (nose or mouth). The current work presents a critical review of the contemporary methods of immune- and chemoprophylaxis and their suitability and applicability in topical mucosal dosage forms for SARS-CoV-2 prophylaxis.

ANTIVIRAL EFFECT OF MOUTHWASHES AGAINST SARS-COV-2: A SYSTEMATIC REVIEW

Objective

This systematic review aimed to evaluate the antiviral effect of mouthwashes against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Material and methods

An electronic search was performed on PubMed, Scopus, Web of Science, Cochrane Library, LILACS, ProQuest, and Google Scholar, and was complemented by a manual search. Both clinical and in vitro studies that focused on the antiviral effect of mouthwashes against SARS-CoV-2 were included. Risk of bias assessment was performed only on the clinical studies using the RoB-2 and ROBINS-I tools.

Results

A total of 907 records were found; after initial selection by title and abstract, 33 full-text articles were selected to be evaluated for eligibility. Finally, a total of 27 studies were included for the qualitative synthesis, including 16 in vitro studies and 11 clinical trials. Antiviral effects were evaluated separately for the in vitro and clinical studies. In vitro studies included mouthwashes containing hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, essential oils, cetylpyridinium chloride, and other compounds; in vivo studies included mouthwashes containing hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, cetylpyridinium chloride, essential oils, chlorine dioxide, β-cyclodextrin-citrox, and sorbitol with xylitol. Povidone-iodine, cetylpyridinium chloride, and essential oils were effective in vitro, while hydrogen peroxide, chlorhexidine digluconate, povidone-iodine, cetylpyridinium chloride, β-cyclodextrin-citrox, and sorbitol with xylitol were effective in vivo. Unclear or high risk of bias was found for almost all clinical studies, and only one study presented with a low risk of bias. No further quantitative analysis was performed.

Conclusion

Although povidone-iodine, cetylpyridinium chloride, and essential oils may be an alternative to reduce the viral load in vitro and in vivo, more studies are needed to determine the real antiviral effect of these different mouthwashes against SARS-CoV-2.

This work was not funded. The protocol was registered in PROSPERO (identification number: CRD42021236134).

Surface contamination with SARS-CoV-2: A systematic review

Little is known about contaminated surfaces as a route of transmission for SARS-CoV- 2 and a systematic review is missing and urgently needed to provide guidelines for future research studies. As such, the aim of the present study was to review the current scientific knowledge and to summarize the existing studies in which SARS-CoV-2 has been detected in inanimate surfaces. This systematic review includes studies since the emergence of SARS-CoV-2, available in PubMed/MEDLINE and Scopus. Duplicate publications were removed, and exclusion criteria was applied to eliminate unrelated studies, resulting in 37 eligible publications. The present study provides the first overview of SARS-CoV-2 detection in surfaces. The highest detection rates occurred in hospitals and healthcare facilities with COVID-19 patients. Contamination with SARS-CoV-2 on surfaces was detected in a wide range of facilities and surfaces. There is a lack of studies performing viability testing for SARS-CoV-2 recovered from surfaces, and consequently it is not yet possible to assess the potential for transmission via surfaces.

The effect of mouthwashes on SARS-CoV-2 viral load: a systematic review

Background

Considering that the oral cavity is a major entryway and reservoir for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the aim of the authors was to perform a systematic review of in vivo and in vitro studies to assess the effectiveness of mouthrinses on SARS-CoV-2 viral load.

Types of Studies Reviewed

The authors searched PubMed, Web of Science, Scopus, MedRxiv, and bioRxiv databases, including in vitro and in vivo studies assessing the virucidal effect of mouthrinses on SARS-CoV-2 or surrogates. From a total of 1,622 articles retrieved, the authors included 39 in this systematic review.

Results

Povidone-iodine was the most studied mouthrinse (14 in vitro and 9 in vivo studies), frequently showing significant reductions in viral load in in vitro assays. Similarly, cetylpyridinium chloride also showed good results, although it was evaluated in fewer studies. Chlorhexidine gluconate and hydrogen peroxide showed conflicting results on SARS-CoV-2 load reduction in both in vitro and in vivo studies.

Practical Implications

Povidone-iodine–based mouthrinses appear to be the best option as an oral prerinse in the dental context for SARS-CoV-2 viral load reduction. Although the results of primary studies are relevant, there is a need for more in vivo studies on mouthrinses, in particular, randomized controlled clinical trials, to better understand their effect on SARS-CoV-2 viral load and infection prevention.