Infectious Disease Management and Control with Povidone Iodine

In-Vitro Determination of Minimum Inhibitory Concentration (MIC) and Contact Time of Povidone-Iodine against Staphylococcus aureus and Klebsiella aerogenes Using Micro Suspension Test, Colorimetric Resazurin Microplate Assay, and Dey Engley Neutralizer Assay

Background and Objective

The human nasal passages host major human pathogens. Recent research suggests that the microbial communities inhabiting the epithelial surfaces of the nasal passages play a key factor in maintaining a healthy microenvironment by affecting both resistance to pathogens and immunological responses. Colonization of the nasal cavity by different pathogens such as Staphylococcus aureus and Klebsiella aerogenes, is associated with a higher postoperative infection morbidity. Povidone-iodine (PVP-I) as an antiseptic has been proven to display high antibacterial, antiviral, and antifungal properties even at low concentrations, and was shown to be effective in the control of infections to limit their impact and spread. It can be used as a topical antiseptic for skin decontamination and wound management, as a nasal spray, or as a gargle. There are different methods in testing the efficacy of potential antimicrobial suspensions. This study aimed to determine the concentration of PVP-I that is most effective in nasal decolonization using microsuspension test and colorimetric minimum inhibitory concentration (MIC) determination assays, resazurin microtiter assay (REMA), and Dey-Engley (D/E) neutralizer assay. The findings of this study will contribute to knowledge regarding the intended use of PVP-I in microbial control, particularly in bacterial infections.

Methods

Several dilutions (2.0%, 1.0%, 0.5%, 0.25%, 0.1% and 0.09%) of commercially bought 10% (10 mg per 100 ml) povidone-iodine were prepared and tested against a standardized inoculum (1x105) of Staphylococcus aureus and Klebsiella aerogenes at different contact times (5 seconds, 10 seconds, 30 seconds, 1 minute, and 5 minutes). Microdilution suspension test was performed to determine the log reduction per variable, while REMA and D/E neutralizer assay were used to determine the MIC. A value of greater than or equal to 5 log reduction was considered effective for microdilution suspension test. Estimates of agreement statistics were used to interpret the results of the assay in which the overall percent agreement (OPA), positive percent agreement (PPA), negative percent agreement (NPA), and Cohen's kappa statistics were calculated.

Results

Povidone-iodine concentration of 0.25% exhibited ≥5 log reduction against K. aerogenes at the minimum contact time of 5 seconds. On the other hand, a slightly higher PVP-I concentration was required to achieve ≥5 log reduction for S. aureus at 0.5% concentration and a minimum contact time of 1 minute. There was an observed concordance of the results of REMA and D/E neutralizer as MIC colorimetric indicators, which yielded an overall test percent agreement of 90.30% (95% CI: 84.73-94.36), and a strong level of agreement (Κ = 0.8, p<0.0001). A lower overall percent agreement for both REMA and D/E neutralizer versus the microsuspension test was observed at 79.17% (Κ = 0.57, p<0.0001) and 78.18% (Κ = 0.55, p<0.0001), respectively.

Conclusion

Low povidone-iodine concentrations (i.e., 0.5% against S. aureus and 0.25% against K. aerogenes) were observed to have bactericidal activity of at least 5 log reduction as rapid as the minimum contact time of 5 seconds. Furthermore, D/E and REMA, as colorimetric indicators, had comparable performance (OPA = 90.30%; Κ = 0.8, p<0.0001) suggesting that both REMA and D/E neutralizer assay may detect the same range of minimum inhibitory concentration for the organisms and disinfectant tested in this study.

Effective Eradication of Mouse Norovirus and Helicobacter spp. in Laboratory Mice (Mus musculus) via Iodine Immersion and Cross-Fostering Technique

Eradication of pathogens from mouse colonies is crucial for scientific research reproducibility and animal welfare. The previously described techniques for eradicating pathogens by rederivation through embryo transfer or caesarian technique can be costly and technically challenging. The objective of our study was to assess the efficacy of iodine immersion combined with cross-fostering for eradicating murine norovirus (MNV) and Helicobacter spp. in laboratory mice. The iodine immersion technique was modified to prevent pathogen transmission and reduce the risk of cannibalism. The hypothesis of this study was that iodine immersion combined with cross-fostering of pups would be as effective at eliminating MNV as it is at clearing Helicobacter in laboratory mice. This study was performed on newborn litters of various mice strains housed in a room positive for both these pathogens. The pups were immersed in warmed, diluted iodine within 48 h of birth, and then cross-fostered to a Swiss Webster dam negative for MNV and Helicobacter. The presence of MNV and Helicobacter in donor dams, weanlings, and adult post-immersion animals was tested using fecal PCR. All 27 litters born to MNV- and Helicobacter-positive dams tested negative for both pathogens at weaning and at 8 wk postweaning. Follow-up PCR exhaust dust testing from the housing racks confirmed a negative status for MNV and Helicobacter over multiple quarterly pathogen screening tests conducted over an 18-mo period. This study is, to our knowledge, the first to demonstrate successful eradication of MNV through iodine immersion combined with cross-fostering, proving this method to be effective for eliminating MNV and Helicobacter spp. in affected colonies.

Enhanced bactericidal effects of povidone-iodine in the presence of silver ions

The rising prevalence of antibiotic-resistant infections worldwide necessitates the development of innovative antimicrobial systems for effective pathogen control. This study investigates the synergistic bactericidal effects of a combined system comprising povidone-iodine (PVP-I) and silver ions (Ag(I)). The PVP-I/Ag(I) system exhibited enhanced bactericidal activity against four key surrogate bacterial species: two Gram-negative bacteria, Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa), and two Gram-positive bacteria, Staphylococcus aureus (S. aureus) and Bacillus subtilis (B. subtilis). Our experiments revealed that Ag(I) interacts with iodide ions (I-) to form silver iodide (AgI). This reaction promotes the formation of hypoiodous acid (HOI), a more potent bactericidal agent than other reactive iodine species (RIS), by shifting the equilibrium of RIS released from PVP-I. Under representative conditions ([PVP-I]0 = 1 mg/L, [Ag(I)]0 = 5 μM, pH = 7.3), the concentration of HOI in the PVP-I/Ag(I) system was 2.4-3.9 times higher than in the PVP-I system alone, aligning with theoretical predictions. The bactericidal efficacy of the PVP-I/Ag(I) system was influenced by pH variations, affecting HOI formation. This system represents a promising tool for rapid and effective microbial control, potentially enhancing public health outcomes.

Far-Ultraviolet C Disinfection Reduces Oxidative Damage to the Cornea Compared to Povidone-Iodine Disinfection

Far-ultraviolet C (far-UVC) light shows promise for pathogen control but its safety and efficacy for corneal disinfection remain unclear. In this study, safe far-UVC dosages were investigated for corneal disinfection and its germicidal performance and oxidative damage potential to 5% povidone-iodine (PVP-I) were compared. Rat corneas were exposed to varying 222 nm far-UVC doses (3-60 mJ/cm2) and assessed for ocular damage, apoptosis, and oxidative stress to determine the safe dose of far-UVC. Far-UVC at 30 mJ/cm2 induced corneal apoptosis and oxidative damage, but 15 mJ/cm2 caused no apoptosis or oxidative damage. At this optimized dose (9 mJ/cm2), far-UVC achieved 90.5% sterilization, exceeding 5% PVP-I (80.8%), with significantly less oxidative damage and cell death in the cornea. In conclusion, our study demonstrates that the use of 5% povidone-iodine (PVP-I) for disinfection results in significant oxidative damage to the corneal tissue. However, a safe dosage of far-UVC light exhibited a promising disinfection effect without causing oxidative damage to the corneal tissue. Far-UVC offers a promising alternative for corneal disinfection but requires careful dosage control (≤30 mJ/cm2) to avoid ocular surface harm.

Review - Expert Opinion on Antibiotics and Antibiotic Resistance in Dermatology

INTRODUCTION

Antibiotic resistance has become a serious, severe problem worldwide. This issue does not only relate to the use of systemic antibiotics but to topical ones as well, like systemic therapies and local treatment of skin and mucosal infections. Antiseptics, an alternative to the topical treatment with antibiotics of wounds and some inflammatory dermatological conditions, tend to be microbicidal and have a broader spectrum of antimicrobial activity than antibiotics. Among these, polyhexanide (PHMB) allows for the control of the infection while avoiding the development of resistance.

OBJECTIVES

Recommendations on the rules of good clinical practice for the management of small wounds, burns and post-traumatic ulcerative wounds, impetigo or folliculitis in the initial stages, and acne.

METHODS

Literature review on the principal topical therapies for small wounds, injuries, impetigo, folliculitis, and acne and a proposal of innovative, highly-tolerated treatments.

RESULTS AND CONCLUSIONS

Given the abuse of topical antibiotics in dermatology, for the treatment of small wounds, injuries, localized folliculitis, impetigo, and acne, the use of alternative topical treatments like polyhexanide and Rigenase® is recommended.

Antiseptics: An expeditious third force in the prevention and management of coronavirus diseases

Notably, severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS) and coronavirus disease 2019 (COVID-19) have all had significant negative impact on global health and economy. COVID-19 alone, has resulted to millions of deaths with new cases and mortality still being reported in its various waves. The development and use of vaccines have not stopped the transmission of SARS coronavirus 2 (SARS-CoV-2), the etiological agent of COVID-19, even among vaccinated individuals. The use of vaccines and curative drugs should be supplemented with adoption of simple hygiene preventive measures in the fight against the spread of the virus, especially for healthcare workers. Several virucidal topical antiseptics, such as povidone-iodine (PVP-I), citrox, cyclodextrins among others, have been demonstrated to be efficacious in the inactivation of SARS-CoV-2 and other coronaviruses in both in vitro and in vivo studies. The strategic application of these virucidal formulations could provide the additional impetus needed to effectively control the spread of the virus. We have here presented a simple dimension towards curtailing the dissemination of COVID-19, and other coronaviruses, through the application of effective oral, nasal and eye antiseptics among patients and medical personnel. We have further discussed the mechanism of action of some of these commonly available virucidal solutions while also highlighting some essential controversies in their use.

Green synthesis of an ionic porous organic polymer for efficient capture of environmentally toxic MnO4- and I3- from water

The syntheses of ionic porous organic polymers (iPOPs) via an ionothermal strategy or using solvents with high boiling points are not environmentally friendly approaches. Furthermore, green synthesis of an ionic porous organic polymer has not been reported to date. The azo-coupling reaction is considered a green synthetic strategy and has been used to obtain a new ionic porous organic polymer (iPOP-6) wherein water is used as a solvent. iPOP-6 turns out to be a useful adsorbent that can scavenge toxic water pollutants (MnO4- and I3-) in an energy efficient manner via an ion exchange based adsorption process. The distribution coefficients (Kd) associated with the removal of MnO4- and I3- are greater than 105 mL g-1 - a desirable feature observed in a superior adsorbent. iPOP-6 can remove such pollutants from water samples collected from different water bodies with good capture efficiency. The removal mechanism was also ratified by theoretical studies. Overall, this work presents a new ionic POP with improved features and performance for water purification applications.

Double Type Detection of Triiodide and Iodide Ions Using a Manganese(III) Porphyrin as Sensitive Compound

A paramagnetic A3B-type Mn(III)-porphyrin was synthesized and characterized by physical-chemical methods (UV-Vis, FT-IR, 1H-NMR spectroscopy). The obtained compound was tested as a sensitive material for the spectrophotometric and potentiometric detection of iodine species. Using UV-Vis spectroscopy, the triiodide anions could be detected with high precision in the concentration interval of 1.02 × 10-5 to 2.3 × 10-5 M, with an LOD of 9.44 × 10-6 M. The PVC-based electrode using DOP as a plasticizer showed a sensitivity toward iodide in a wide concentration range of 1.0 × 10-5 to 1.0 × 10-1 M, with an LOD of 8.0 × 10-6 M. Both methods are simple, low-cost, and efficient for the detection of iodine species in synthetic samples and pharmaceuticals.

New Insights Regarding the Use of Relevant Synthetic Compounds in Dentistry

Worldwide, synthetic compounds are used for both in-office and at-home dental care. They are a valuable resource for both prophylactic and curative treatments for various dental problems, such as tooth decay, periodontal diseases, and many more. They are typically preferred due to their broad range of actions and ability to produce targeted, rapid, and long-lasting effects. Using a 0.12% chlorhexidine mouthwash is capable of reducing the plaque index from 47.69% to 2.37% and the bleeding index from 32.93% to 6.28% after just 2 weeks. Mouthwash with 0.1% OCT is also highly effective, as it significantly lowered the median plaque index and salivary bacterial counts in 152 patients in 5 days compared to a control group (p < 0.0001), while also reducing the gingival index (p < 0.001). When povidone-iodine was used as an irrigant during the surgical removal of mandibular third molars in 105 patients, it resulted in notably lower pain scores after 2 days compared to a control group (4.57 ± 0.60 vs. 5.71 ± 0.45). Sodium hypochlorite is excellent for root canal disinfection, as irrigating with 1% NaOCl completely eliminated the bacteria from canals in 65% patients. A 0.05% CPC mouthwash proved effective for perioperative patient care, significantly decreasing gingival bleeding (p < 0.001) and suppressing Streptococcus levels even one week post-surgery. Lastly, a 6% H2O2 paint-on varnish and 6% H2O2 tray formulations successfully bleached the teeth of 40 patients, maintaining a noticeably whiter appearance up to the 6-month follow-up, with significant color differences from the baseline (p < 0.005). Synthetic compounds have a large research base, which also provides a greater awareness of their mechanism of action and potential adverse effects. For a better understanding of how they work, several methods and assays are performed. These are protocolary techniques through which a compound's efficacy and toxicity are established.

One-time low concentration betadine eye wash: A novel treatment for epidemic viral conjunctivitis for accelerated recovery

Purpose

This study aims to renew the management of viral epidemic conjunctivitis by introducing a one-time, low-concentration ocular surface povidone-iodine (LOS-pI) wash.

Methods

Among the 3,002 patients screened, 1,328 with acute conjunctivitis were categorized into two groups. Group A (664 patients) underwent a 1% betadine wash in addition to the standard treatment protocol (Eye Lubricant + Moxifloxacin 0.5% eyedrops), while Group B (664 patients) followed the standard protocol alone. In cases of membranous conjunctivitis, manual membrane removal was performed. Treatment responses were observed daily for three days, followed by weekly assessments for two additional weeks.

Results

Co-infection of adenovirus with enterovirus was found to be the main cause, often accompanied by staphylococcal superinfection. Group A showed complete resolution of conjunctival inflammation, with a remarkable 76.05% of patients experiencing improvement within an average of 2.6±0.51 days, in contrast to Group B's average of 7.5±1.1 days (p <0.05). Additionally, 13% of Group B patients with recalcitrant conjunctivitis significantly recovered following the 1% betadine wash. Complications (subconjunctival hemorrhage: 34.04%, superficial punctate keratitis: 6.02%) were more prevalent in Group B.

Discussion

The authors hypothesized that a single wash with betadine is sufficient to reduce disease duration and prevent secondary infections and complications. The core strength of our study lies in its substantial sample size. To our knowledge, no similar previous research has been conducted, on such a larger scale.

Conclusion

Viral conjunctivitis brings discomfort, work absenteeism, and financial burden. A single low-concentration betadine wash expedites recovery and reduces complications in acute infective conjunctivitis. This approach significantly enhances patient outcomes and alleviates the socioeconomic impact of the condition.

Aristolochia bracteolata flower extract based phytosynthesis and characterization of AgNPs: Antimicrobial, antidiabetic, and antioxidant activities potential assessment

The study was carried out to evaluate the effectiveness of the Aristolochia bracteolata water flower extract-mediated AgNPs synthesis and assess their antimicrobial potential. According to the experimental and analytical results, A. bracteolata flower extract can produce valuable AgNPs. The characteristic features of these AgNPs were assessed with UV-visible spectrophotometer, Fourier transform-infrared spectroscopy, Transmission Electron Microscope, Scanning Electron Microscopy, as well as. Under UV-vis. spectrum results, showed major peak at 430 nm and recorded essential functional groups responsible for reducing, capping, and stabilizing AgNPs by FT-IR analysis. In addition, the size and shape of the synthesized AgNPs were found as 21.11-25.17 nm and spherical/octahedral shape. The A. bracteolata fabricated NPs showed remarkable antimicrobial activity against fish bacterial pathogens (V. parahaemolytics, Serratia sp., B. subtilis, and E. coli) as well as common fungal pathogens (A. niger, C. albicans, A. flavus, and A. terreus) at the quantity of 100 μg mL-1 than positive controls. Nevertheless, it was not effective against human bacterial pathogens. It concludes that AgNPs synthesized from A. bracteolata aqueous flower extract have excellent antimicrobial activity and may have a variety of biomedical applications.

Lessons should be learned: Why did we not learn from the Spanish flu?

COVID-19 has become a global pandemic that has affected millions of people worldwide. The disease is caused by the novel coronavirus that was first reported in Wuhan, China, in December 2019. The virus is highly contagious and can spread from person to person through respiratory droplets when an infected person coughs, sneezes, talks, or breathes. The symptoms of COVID-19 include fever, cough, and shortness of breath, and in severe cases, it can lead to respiratory failure, pneumonia, and death. The Spanish flu, caused by the H1N1 influenza virus, and the COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 are two of the most significant global health crises in history. While these two pandemics occurred almost a century apart and are caused by different types of viruses, there are notable similarities in their impact, transmission, and public health responses. Here are some key similarities between the Spanish flu and SARS-CoV-2. The Spanish flu pandemic of 1918-1919 stands as one of the deadliest pandemics in human history, claiming the lives of an estimated 50 million people worldwide. Its impact reverberated across continents, leaving behind a legacy of devastation and lessons that, unfortunately, seem to have been forgotten or ignored over time. Despite the advancements in science, medicine, and public health in the intervening century, humanity found itself facing a strikingly similar situation with the outbreak of the COVID-19 pandemic. Additionally, amidst the search for effective measures to combat COVID-19, novel approaches such as iodine complexes, such as Iodine-V has emerged as potential interventions, reflecting the ongoing quest for innovative solutions to mitigate the impact of pandemics. This raises the poignant question: why did we not learn from the Spanish flu?

Antibacterial and antibiofilm activities of iodinated hydrocarbons against Vibrio parahaemolyticus and Staphylococcus aureus

Food-related illnesses have become a growing public concern due to their considerable socioeconomic and medical impacts. Vibrio parahaemolyticus and Staphylococcus aureus have been implicated as causative organisms of food-related infections and poisoning, and both can form biofilms which confer antibiotic resistance. Hence, the need for continuous search for compounds with antibiofilm and antivirulence properties. In this study, 22 iodinated hydrocarbons were screened for their antibiofilm activity, and of these, iodopropynyl butylcarbamate (IPBC) was found to effectively control biofilm formation of both pathogens with a MIC of 50 µg/mL which was bactericidal to V. parahaemolyticus and S. aureus. Microscopic studies confirmed IPBC inhibits biofilm formation of both bacteria and also disrupted their mixed biofilm formation. Furthermore, IPBC suppressed virulence activities such as motility and hemolytic activity of V. parahaemolyticus and the cell surface hydrophobicity of S. aureus. It exhibited a preservative potential against both pathogens in a shrimp model. IPBC disrupted the cell membrane of S. aureus and V. parahaemolyticus and differentially affected gene expressions related to biofilm formation and virulence. Additionally, it displayed broad-spectrum antibiofilm activities against other clinically relevant pathogens. These findings indicate IPBC offers a potential means of controlling infections mediated by Vibrio and Staphylococcus biofilms.

Preparation and characterizations of antibacterial iodine-containing coatings on pure Ti

Iodine-containing coatings were prepared on pure Ti surfaces via electrochemical deposition to enhance their antibacterial properties. The factors influencing iodine content were analyzed using an orthogonal experiment. The electrochemically deposited samples were characterized using scanning electron microscopy with energy dispersive spectroscopy and X-ray photoelectron spectroscopy, and their antibacterial properties and cytotoxicity were evaluated. The results showed that changing the deposition time is an effective way to control the iodine content. The iodine content, coating thickness, and adhesion of the samples increased with deposition time. Iodine in the coatings mainly exists in three forms, which are I2, I3-, and pentavalent iodine. For samples with iodine-containing coatings, the antibacterial ratios against E. coli and S. aureus were greater than 90% and increased with increasing iodine content. Although the samples with iodine-containing coatings showed some inhibition of the proliferation of MC3T3-E1 cells, the cell viabilities were all higher than 80%, suggesting that iodine-containing coatings are biosafe.

Evaluation of dermal toxicity and toxicokinetics of povidone‑iodine in Göttingen minipigs

BACKGROUND

Povidone‑iodine (PVP-I) is an effective and commonly used broad-spectrum antiseptic; limited information exists around its long-term safety and impact on endocrine disruption. We assessed the dermal toxicity and toxicokinetics following a once-daily application of 7.5% (w/v) and 10% (w/v) PVP-I in Göttingen Minipigs® for up to 39 weeks.

METHODS

An in vivo study was conducted in male (n = 27) and female (n = 27) minipigs. Animals were randomized into untreated control, 7.5% and 10% PVP-I, and matching vehicle treatment groups. Animals were assessed for general in-life measurements, including skin irritation and organ weights. Serum samples were analyzed for PVP, total iodine, triiodothyronine [T3], thyroxine [T4], thyroid stimulating hormone [TSH], and toxicokinetic parameters.

RESULTS

Neither 7.5% nor 10% PVP-I affected general in-life measurements. Increased mean thyroid gland absolute weights were noted with 7.5% and 10% PVP-I. Serum levels of PVP, T3, T4, and TSH in the 7.5% and 10% PVP-I treatment group animals were similar to those in vehicle treatment group animals. Mean total serum iodine concentration was 52- and 13-fold higher with 7.5% and 10% PVP-I, respectively, vs respective vehicle treatments. There was no dose-dependent increase in mean maximum serum concentration and area under the curve from 0 to 24 h for PVP, T3, T4, and TSH, nor accumulation of PVP, T3, T4, or TSH in the study.

CONCLUSION

Once-daily dermal application of 7.5% and 10% PVP-I for up to 39 weeks was safe and well tolerated in Göttingen Minipigs® and was not associated with skin irritation, thyroid dysfunction, or endocrine disruption. As the anatomy and physiology of the minipig skin closely resembles that of human skin, the findings of this study suggest that 7.5% and 10% PVP-I may be translated into antimicrobial benefits for humans without the risk of endocrine disruption.

Comparative efficacy of topical povidone-iodine and chlorhexidine gel on dental plaque regrowth in toddlers: A randomized controlled trial

OBJECTIVES

This study aimed to compare and evaluate the efficacy of topical use of povidone-iodine (PVP-I) solution and chlorhexidine (CHX) gel on dental plaque regrowth after 3 and 7 days in toddlers aged 24-36 months.

MATERIALS AND METHODS

A randomized controlled trial that included 45 healthy toddlers aged 24-36 months, who were randomly assigned to three groups. The first group received a placebo (distilled water (DW)) (negative control). The second group received topical CHX gel (0.2% w/v) (positive control). The third group received topical PVP-I solution (10% w/v). Plaque accumulation was measured at the baseline (t0 ), after 3 days (t1 ) and after 7 days (t2 ) using the Turesky-modified Quigley-Hein plaque index (TMQHPI). Oral hygiene practices were prohibited during the trial period. The trial ID is ACTRN12623000567628.

RESULTS

In the DW group, the mean of the TMQHPI score was 1.89 ± 0.67 at t0 and decreased to 1.45 ± 0.66 at t1 (p = .028). Similarly, in the CHX group, the mean of the TMQHPI score was 1.83 ± 1.06 at t0 and decreased to 1.02 ± 0.99 at t1 (p = .033). Regarding the PVP-I group, the mean of the TMQHPI score went from 1.84 ± 0.85 to 1.01 ± 0.61 at t1 and then increased to 1.57 ± 0.74 at t2 . Those changes were statistically significant (p = .001) and (p = .002), respectively. No statistically significant difference was noted between TMQHPI scores at t0 (p = .789). Regarding t1 and t2 , no statistically significant difference was found between the three groups (p > .05).

CONCLUSION

CHX and PVP-I efficacy lasted only for 3 days, and PVP-I was not superior to CHX in terms of plaque control in toddlers. However, further studies are needed to determine the long-term efficacy of these antiplaque agents in toddlers.

Anti-influenza Activity of Povidone-Iodine-Integrated Materials

Personal protective equipment (PPE), including medical masks, should be worn for preventing the transmission of respiratory pathogens via infective droplets and aerosols. In medical masks, the key layer is the filter layer, and the melt-blown nonwoven fabric (NWF) is the most used fabric. However, the NWF filter layer cannot kill or inactivate the pathogens spread via droplets and aerosols. Povidone-iodine (PVP-I) has been used as an antiseptic solution given its potent broad-spectrum activity against pathogens. To develop PPE (e.g., medical masks) with anti-pathogenic activity, we integrated PVP-I into nylon-66 NWF. We then evaluated its antiviral activity against influenza A viruses by examining the viability of Madin-Darby canine kidney (MDCK) cells after inoculation with the virus strains exposed to the PVP-I-integrated nylon-66 NWF. The PVP-I nylon-66 NWF protected the MDCK cells from viral infection in a PVP-I concentration-dependent manner. Subsequently, we found to integrate PVP-I into nylon-66 and polyurethane materials among various materials. These PVP-I materials were also effective against influenza virus infection, and treatment with PVP-I nylon-66 NWF showed the highest cell survival among all the tested materials. PVP-I showed anti-influenza A virus activity when used in conjunction with PPE materials. Moreover, nylon-66 NWF integrated with PVP-I was found to be the best material to ensure anti-influenza activity. Therefore, PVP-I-integrated masks could have the potential to inhibit respiratory virus infection. Our results provide new information for developing multi-functional PPEs with anti-viral activity by integrating them with PVP-I to prevent the potential transmission of respiratory viruses.

Preprocedural Viral Load Effects of Oral Antiseptics on SARS-CoV-2 in Patients with COVID-19: A Systematic Review

(1) There are limited clinical trials to support the effectiveness of mouth rinses when used as a preprocedural rinse against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This systematic review aims to evaluate the efficacy of antiseptic mouth rinses as a preprocedural rinse in reducing SARS-CoV-2 oral viral load in-vivo. (2) Methods: A literature search was conducted through November 2022 for the following databases: PubMed, Web of Science, Cochrane Library, and Google Scholar. The evaluated outcomes were quantitative changes in viral load and the statistical significance of that change after using antiseptic mouth rinses. (3) Results: 14 randomized controlled trials (RCT) were selected for risk of bias assessment and data extraction. (4) Conclusion: Within the limits of this systematic review, preprocedural mouth rinses may significantly reduce SARS-CoV-2 in the mouth, thus, reducing the viral particles available for airborne dispersion. Preprocedural mouth rinses may be an effective strategy for reducing airborne SARS-CoV-2 dispersion in the environment. Their use may be a preventive strategy to reduce the spread of COVID-19 in selected medical and healthcare facilities, including dental clinics. Potential preprocedural mouth rinses are identified for use as an integral part of safe practice for healthcare protocols. This systematic review was registered with the National Institute for Health Research, international prospective register of systematic reviews (PROSPERO): CRD42022315177.

Cell death and barrier disruption by clinically used iodine concentrations

Povidone-iodine (PVP-I) inactivates a broad range of pathogens. Despite its widespread use over decades, the safety of PVP-I remains controversial. Its extended use in the current SARS-CoV-2 virus pandemic urges the need to clarify safety features of PVP-I on a cellular level. Our investigation in epithelial, mesothelial, endothelial, and innate immune cells revealed that the toxicity of PVP-I is caused by diatomic iodine (I2), which is rapidly released from PVP-I to fuel organic halogenation with fast first-order kinetics. Eukaryotic toxicity manifests at below clinically used concentrations with a threshold of 0.1% PVP-I (wt/vol), equalling 1 mM of total available I2 Above this threshold, membrane disruption, loss of mitochondrial membrane potential, and abolition of oxidative phosphorylation induce a rapid form of cell death we propose to term iodoptosis. Furthermore, PVP-I attacks lipid rafts, leading to the failure of tight junctions and thereby compromising the barrier functions of surface-lining cells. Thus, the therapeutic window of PVP-I is considerably narrower than commonly believed. Our findings urge the reappraisal of PVP-I in clinical practice to avert unwarranted toxicity whilst safeguarding its benefits.

Aqueous Povidone-Iodine Versus Normal Saline For Intraoperative Wound Irrigation on The Incidence of Surgical Site Infection in Clean-Contaminated Wounds After Gastroenterological Surgery: A Single-Institute, Prospective, Blinded-Endpoint, Randomized Controlled Trial

OBJECTIVE

This trial evaluated the superiority of intraoperative wound irrigation (IOWI) with aqueous povidone-iodine (PVP-I) compared with that with saline for reducing the incidence of surgical site infection (SSI).

BACKGROUND

IOWI with aqueous PVP-I is recommended for the prevention of SSI by the World Health Organization and the Centers for Disease Control and Prevention, although the evidence level is low.

METHODS

This single institute in Japan, prospective, randomized, blinded-endpoint trial was conducted to assess the superiority of IOWI with aqueous PVP-I in comparison with IOWI with saline for reducing the incidence of SSI in clean-contaminated wounds after gastroenterological surgery. Patients 20 years or older were assessed for eligibility, and the eligible participants were randomized at a 1:1 ratio using a computer-generated block randomization. In the study group, IOWI was performed for 1 minute with 40 mL of aqueous 10% PVP-I before skin closure. In the control group, the procedure was performed with 100 mL of saline. Participants, assessors, and analysts were masked to the treatment allocation. The primary outcome was the incidence of incisional SSI in the intention-to-treat set.

RESULTS

Between June 2019 and March 2022, 941 patients were randomized to the study group (473 patients) or the control group (468 patients). The incidence of incisional SSI was 7.6% in the study group and 5.1% in the control group (risk difference 0.025, 95% CI -0.006 to 0.056; risk ratio 1.484, 95% CI 0.9 to 2.448; P =0.154).

CONCLUSION

The current recommendation of IOWI with aqueous PVP-I should be reconsidered.

Reduction of SARS-CoV-2 salivary viral load with pre-procedural mouth rinses: a randomised, controlled, clinical trial

Introduction The purpose of this study was to test the short-term efficacy of four commercial mouthwashes versus water in reducing SARS-CoV-2 viral load in the oral cavity over clinically relevant time points.Methods In total, 32 subjects that were proven SARS-CoV-2-positive via polymerase chain reaction (PCR)-based diagnostic test were recruited and randomised into five parallel arms. Cycle threshold (Ct) values were compared in saliva samples between the groups, as well as within the groups at baseline (pre-rinse), zero hours, one hour and two hours post-rinse, using SARS-CoV-2 reverse transcription-PCR analysis.Results We observed a significant increase in Ct values in saliva samples collected immediately after rinsing with all the four mouthwashes - 0.12% chlorhexidine gluconate, 1.5% hydrogen peroxide, 1% povidone iodine, or Listerine - compared to water. A sustained increase in Ct values for up to two hours was only observed in the Listerine and chlorohexidine gluconate groups. We were not able to sufficiently power this clinical trial, so the results remain notional but encouraging and supportive of findings in other emerging mouthwash studies on COVID-19, warranting additional investigations.Conclusions Our evidence suggests that in a clinical setting, prophylactic rinses with Listerine or chlorhexidine gluconate can potentially reduce SARS-CoV-2 viral load in the oral cavity for up to two hours. While limited in statistical power due to the difficulty in obtaining this data, we advocate for pre-procedural mouthwashing, like handwashing, as an economical and safe additional precaution to help mitigate the transmission of SARS-CoV-2 from a potentially infected patient to providers.

Comparison of antibiofilm activity of low-concentrated hypochlorites vs polyhexanide-containing antiseptic

Chronic wound infection is highly associated with morbidity and endangers the patient's life. Therefore, wound care products must have a potent antimicrobial and biofilm-eradicating effect. In this work, the antimicrobial/antibiofilm activity of two low-concentrated chlorine-based and releasing solutions was investigated on a total of 78 strains of methicillin-resistant Staphylococcus aureus, Pseudomonas aeruginosa, and Candida albicans, using the cohesive spectrum of in vitro settings, including microtiter plate models, biofilm-oriented antiseptic test, cellulose-based biofilm model, biofilm bioreactors and Bioflux model. The antiseptic containing polyhexamethylene biguanide was used in the character of usability control of performed tests. The results obtained by static biofilm models indicate that low-concentrated chlorine-based and releasing solutions display none to moderate antibiofilm activity, while data obtained by means of the Bioflux model, providing flow conditions, indicate the moderate antibiofilm activity of substances compared with the polyhexanide antiseptic. Considering in vitro data presented in this manuscript, the earlier reported favorable clinical results of low-concentrated hypochlorites should be considered rather an effect of their rinsing activity combined with low cytotoxicity but not the antimicrobial effect per se. For the treatment of heavily biofilm-infected wounds, polyhexanide should be considered the agent of choice because of its higher efficacy against pathogenic biofilms.

Broad-Spectrum Antimicrobial Activity of Oftasecur and Visuprime Ophthalmic Solutions

Due to the wide etiology of conjunctivitis, the expensive and time-consuming diagnosis requires new therapeutic strategies with broad-spectrum antimicrobial activity and nonselective mechanisms of action. In this context, eye drops could provide an alternative to conventional antimicrobial therapies. Here, we compare the antibacterial and antiviral activity of Oftasecur and Visuprime, commercially available ophthalmic solutions. Cytotoxicity assay was performed on Vero CCL-81 cells by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) test. Antibacterial efficacy was evaluated on Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, Escherichia coli, and Klebsiella pneumoniae by disk diffusion, broth microdilution methods, and time-killing tests. Furthermore, the antiviral activity against HSV-1 was estimated by co-treatment, cell and viral pretreatment and post-treatment, via plaque reduction assay, fluorescence assessment (GFP-engineered HSV-1), and real-time PCR. After 24 h of exposure, Oftasecur and Visuprime showed a volume-inducing 50% of cytotoxicity of 125 and 15.8 μL, respectively Oftasecur and Visuprime induced 90% antibacterial activity in response to mean volume of 10.0 and 4.4 µL for Gram-positive and Gram-negative strains, respectively. Oftasecur exerted bactericidal action on both bacterial populations, while Visuprime was bacteriostatic on Gram-negative strains and slightly bactericidal on Gram-positive bacteria. A major impact on infectivity occurred by exposure of viral particles to the ophthalmic solutions. In detail, 50% of inhibition was verified by exposing the viral particles to 3.12 and 0.84 μL of Oftasecur and Visuprime, respectively, for 1 h. The reduction of the fluorescence and the expression of the viral genes confirmed the recorded antiviral activity. Due to their high antimicrobial efficiency, Oftasecur and Visuprime could represent a valid empirical strategy for the treatment of conjunctivitis.

Identifying and prioritizing resilient health system units to tackle the COVID-19 pandemic

Since human health greatly depends on a healthy and risk-free social environment, it is very important to have a concept to focus on improving epidemiology capacity and potential along with economic perspectives as a very influential factor in the future of societies. Through responsible behavior during an epidemic crisis, the health system units can be utilized as a suitable platform for sustainable development. This study employs the Best-Worst Method (BWM) in order to develop a system for identifying and ranking health system units with understanding the nature of the epidemic to help the World Health Organization (WHO) in recognizing the capabilities of resilient health system units. The purpose of this study is to identify and prioritize the resilient health system units for dealing with Coronavirus. The statistical population includes 215 health system units in the world and the opinions of twenty medical experts are also utilized as an informative sample to localize the conceptual model of the study and answer the research questionnaires. The resilient health system units of the world are identified and prioritized based on the statistics of "Total Cases", "Total Recovered", "Total Deaths", "Active Cases", "Serious", "Total Tests" and "Day of Infection". The present descriptive cross-sectional study is conducted on Worldometer data of COVID-19 during the period of 17 July 2020 at 8:33 GMT. According to the results, the factors of "Total Cases", "Total Deaths", "Serious", "Active Cases", "Total Recovered", "Total Tests" and "Day of Infection" are among the most effective ones, respectively, in order to have a successful and optimal performance during a crisis. The attention of health system units to the identified important factors can improve the performance of epidemiology system. The WHO should pay more attention to low-resilience health system units in terms of promoting the health culture in crisis management of common viruses. Considering the importance of providing health services as well as their significant effect on the efficiency of the world health system, especially in critical situations, resilience analysis with the possibility of comparison and ranking can be an important step to continuously improve the performance of health system units.

Bacterial sensitivity to chlorhexidine and povidone-iodine antiseptics over time: a systematic review and meta-analysis of human-derived data

Surgical site infection (SSI) is the most common complication of surgery, increasing healthcare costs and hospital stay. Chlorhexidine (CHX) and povidone-iodine (PVI) are used for skin antisepsis, minimising SSIs. There is concern that  resistance to topical biocides may be emergeing, although the potential clinical implications remain unclear. The objective of this systematic review was to determine whether the minimum bactericidal concentration (MBC) of topical preparations of CHX or PVI have changed over time, in microbes relevant to SSI. We included studies reporting the MBC of laboratory and clinical isolates of common microbes to CHX and PVI. We excluded studies using non-human samples and antimicrobial solvents or mixtures with other active substances. MBC was pooled in random effects meta-analyses and the change in MBC over time was explored using meta-regression. Seventy-nine studies were included, analysing 6218 microbes over 45 years. Most studies investigated CHX (93%), with insufficient data for meta-analysis of PVI. There was no change in the MBC of CHX to Staphylococci or Streptococci over time. Overall, we find no evidence of reduced susceptibility of common SSI-causing microbes to CHX over time. This provides reassurance and confidence in the worldwide guidance that CHX should remain the first-choice agent for surgical skin antisepsis.

Molecular identification, characterization, and antagonistic activity profiling of Bacillus cereus LOCK 1002 along with the in-silico analysis of its presumptive bacteriocins

Objectives

This research aimed to isolate, identify, and characterize a new strain of Bacillus cereus through different molecular biology approaches so that it could be further studied for therapeutic purposes against selective enteric pathogens.

Materials and Methods

Pure isolates of B. cereus were prepared from buffalo yogurt samples in REMBA medium. Initially, the morphological, physiological, and biochemical properties were studied accordingly. Following the tests, the molecular identification for the strain identification was conducted through plasmid DNA extraction, PCR, agarose gel electrophoresis, and 16S rRNA sequencing up to 1.37 kb. Afterward, the antibiotic sensitivity [Epsilometer test (E-Test)] and antifungal activity were tested considering different concentrations. Being classified from the aforementioned tests, a comprehensive antimicrobial activity test was conducted using the cell-free-supernatant (CFS) of the test strain against selective enteric pathogens in humans in vitro. Besides, the different clusters of genes were identified and characterized for understanding the presumptive bacteriocins present in the CFS of the strain in silico, where molecular string properties were calculated. Finally, the evolutionary relationship among diversified bacteriocins synthesized by different Bacillus strains was studied to predict the CFS-containing bacteriocins of the new strain.

Results

Purified isolates of B. cereus were Gram-positive rods and showed significant tolerance (p < 0.0001) to different concentrations of pH, phenol, bile salt, and NaCl. 16S rRNA revealed the strain as LOCK 1002, which was strongly sensitive to all the antibiotics used and resistant to selective antifungal agents. The CFS of B. cereus LOCK 1002 was found to be a very promising antagonist to all the enteric pathogens used in the culture condition. Two gene clusters were predicted to be interconnected and responsible for different presumptive bacteriocins.

Conclusion

The newly identified LOCK 1002 can be a very potent strain of B. cereus in use as an antimicrobial agent for having different bacteriocin coding gene clusters.

Antibacterial and Antibiofilm Properties of Self-Assembled Dipeptide Nanotubes

Over recent decades, multidrug-resistant pathogens have become a global concern, with WHO even considering it one of the biggest threats to global health, food security, and development today, which led to the search for alternative antibacterial agents. A special class is formed by peptides composed by the diphenylalanine motif whose antibacterial properties result from their supramolecular arrangement into nanotubes. However, several other dipeptides that also form nanotubes have been largely overlooked. Here, we present the antibacterial activity of four dipeptide nanotubes. The results point to diverse mechanisms through which dipeptide nanotubes exert their effect against bacteria. Antibacterial activity was similar for dipeptide nanotubes sufficiently wide to allow water flux while dipeptides displaying smaller channels were inactive. This suggests that two of the tested dipeptides, L-Phe-L-Phe (FF, diphenylalanine) and L-Leu-L-Ser (LS), are pore forming structures able to induce membrane permeation and affect cellular hydration and integrity. Of these two dipeptides, only FF demonstrated potential to inhibit biofilm formation. The amyloid-like nature and hydrophobicity of diphenylalanine assemblies are probably responsible for their adhesion to cell surfaces preventing biofilm formation and bacteria attachment.

Application of antimicrobial, potential hazard and mitigation plans

The tremendous rise in the consumption of antimicrobial products had aroused global concerns, especially in the midst of pandemic COVID-19. Antimicrobial resistance has been accelerated by widespread usage of antimicrobial products in response to the COVID-19 pandemic. Furthermore, the widespread use of antimicrobial products releases biohazardous substances into the environment, endangering the ecology and ecosystem. Therefore, several strategies or measurements are needed to tackle this problem. In this review, types of antimicrobial available, emerging nanotechnology in antimicrobial production and their advanced application have been discussed. The problem of antimicrobial resistance (AMR) due to antibiotic-resistant bacteria (ARB)and antimicrobial resistance genes (AMG) had become the biggest threat to public health. To deal with this problem, an in-depth discussion of the challenges faced in antimicrobial mitigations and potential alternatives was reviewed.

Effect of povidone-iodine and propanol-based mecetronium ethyl sulphate on antimicrobial resistance and virulence in Staphylococcus aureus

Background

Reports are available on cross-resistance between antibiotics and biocides. We evaluated the effect of povidone-iodine (PVP-I) and propanol-based mecetronium ethyl sulphate (PBM) on resistance development, antibiotics cross-resistance, and virulence in Staphylococcus aureus.

Methods

The minimum inhibitory concentration (MIC) of PVP-I and PBM were determined against S. aureus ATCC 25923 using the agar-dilution method. Staphylococcus aureus ATCC 25923 was subjected to subinhibitory concentrations of the tested biocides in ten consecutive passages followed by five passages in a biocide-free medium; MIC was determined after each passage and after the fifth passage in the biocide-free medium. The developed resistant mutant was tested for cross-resistance to different antibiotics using Kirby-Bauer disk diffusion method. Antibiotic susceptibility profiles as well as biocides’ MIC were determined for 97 clinical S. aureus isolates. Isolates were categorized into susceptible and resistant to the tested biocides based on MIC distribution pattern. The virulence of the biocide-resistant mutant and the effect of subinhibitory concentrations of biocides on virulence (biofilm formation, hemolysin activity, and expression of virulence-related genes) were tested.

Results

PVP-I and PBM MIC were 5000 μg/mL and 664 μg/mL. No resistance developed to PVP-I but a 128-fold increase in PBM MIC was recorded, by repeated exposure. The developed PBM-resistant mutant acquired resistance to penicillin, cefoxitin, and ciprofloxacin. No clinical isolates were PVP-I-resistant while 48.5% were PBM-resistant. PBM-resistant isolates were more significantly detected among multidrug-resistant isolates. PVP-I subinhibitory concentrations (¼ and ½ of MIC) completely inhibited biofilm formation and significantly reduced hemolysin activity (7% and 0.28%, respectively). However, subinhibitory concentrations of PBM caused moderate reduction in biofilm activity and non-significant reduction in hemolysin activity. The ½ MIC of PVP-I significantly reduced the expression of hla, ebps, eno, fib, icaA, and icaD genes. The virulence of the biocide-resistant mutant was similar to that of parent strain.

Conclusion

PVP-I is a highly recommended antiseptic for use in healthcare settings to control the evolution of high-risk clones. Exposure to PVP-I causes no resistance-development risk in S. aureus, with virulence inhibition by subinhibitory concentrations. Also, special protocols need to be followed during PBM use in hospitals to avoid the selection of resistant strains.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13756-022-01178-9.

The efficacy of mouthwashes in reducing SARS-CoV-2 viral loads in human saliva: A systematic review

This systematic review aimed to evaluate existing randomized controlled trials (RCT) and cohort studies on the efficacy of mouthwashes in reducing SARS-CoV-2 viral loads in human saliva. Searches with pertinent search terms were conducted in PubMed, MEDLINE, Scopus, and Web of Science databases for relevant records published up to Oct 15, 2022. Google Scholar and ProQuest were searched for grey literature. Manual searches were conducted as well for any pertinent articles. The protocol was prospectively registered at PROSPERO (CRD42022324894). Eligible studies were critically appraised for risk of bias and quality of evidence to assess the efficacy of mouthwash in reducing the SARS-CoV-2 viral load in human saliva. Eleven studies were included. The effect on viral load using various types of mouthwash was observed, including chlorhexidine (CHX), povidone-iodine (PI), cetylpyridinium chloride (CPC), hydrogen peroxide (HP), ß-cyclodextrin-citrox mouthwash (CDCM), and Hypochlorous acid (HCIO). Eight articles discussed CHX use. Five were found to be significant and three did not show any significant decrease in viral loads. Eight studies reviewed the use of PI, with five articles identifying a significant decrease in viral load, and three not showing a significant decrease in viral load. HP was reviewed in four studies, two studies identified significant viral load reductions, and two did not. CPC was reviewed in four studies, two of which identified significant viral load reductions, and two did not. CDCM was reviewed in one article which found a significant decrease in viral load reduction. Also, HCIO which was evaluated in one study indicated no significant difference in CT value. The current systematic review indicates that based on these eleven studies, mouthwashes are effective at reducing the SARS-CoV-2 viral load in human saliva. However, further studies should be performed on larger populations with different mouthwashes. The overall quality of evidence was high.

Remote Eradication of Bacteria on Orthopedic Implants via Delayed Delivery of Polycaprolactone Stabilized Polyvinylpyrrolidone Iodine

Bacteria-associated late infection of the orthopedic devices would further lead to the failure of the implantation. However, present ordinary antimicrobial strategies usually deal with early infection but fail to combat the late infection of the implants due to the burst release of the antibiotics. Thus, to fabricate long-term antimicrobial (early antibacterial, late antibacterial) orthopedic implants is essential to address this issue. Herein, we developed a sophisticated MAO-I₂-PCLx coating system incorporating an underlying iodine layer and an upper layer of polycaprolactone (PCL)-controlled coating, which could effectively eradicate the late bacterial infection throughout the implantation. Firstly, micro-arc oxidation was used to form a microarray tubular structure on the surface of the implants, laying the foundation for iodine loading and PCL bonding. Secondly, electrophoresis was applied to load iodine in the tubular structure as an efficient bactericidal agent. Finally, the surface-bonded PCL coating acts as a controller to regulate the release of iodine. The hybrid coatings displayed great stability and control release capacity. Excellent antibacterial ability was validated at 30 days post-implantation via in vitro experiments and in vivo rat osteomyelitis model. Expectedly, it can become a promising bench-to-bedside strategy for current infection challenges in the orthopedic field.

Evaluation of Renessans (Iodine Complex Molecule) Safety in Human Beings: An Open-Labeled Clinical Study

Extensive studies on evaluation of effectiveness/toxicity of different oral doses of iodine have not been explored yet. An open-labeled phase I clinical studies were conducted using iodine complex based research compound called Renessans. Study groups were observed for development of any adverse/serious adverse events and alteration in laboratory values of vital organs, TSH and T4 hormones before and after the administration of the products. Out of 31 consented individuals, 24 healthy individuals participated in the study. Rate of occurrence of mild Adverse Events (AEs) in group A was 8.3% while in Group B it was 33.33% but these Adverse Events were self-resolving. After completion of study treatment blood serum iodine was reported to 3522.88 µg/l while mean urine iodine concentration (MUIC) was greater than 2000 µg/l. Hormonal and vital organ’s testing revealed that all parameters of TSH and T4, LFT, CBC, RFT remained unaltered except from ALT-SGPT (P-value = .006) and AST-SGOT (P-value = .02). From all of these findings, it can be inferred that the use of Renessans formulations did not pose any sort of risk to human body and can be considered safe through this pilot study.

Preventive factors, diagnosis, and management of injection-related endophthalmitis: a literature review

BACKGROUND

Intravitreal medication injections represent the gold standard treatment for a variety of potentially blinding chorioretinal vascular diseases. Despite their excellent safety profile, they are associated with the feared complication of injection-related endophthalmitis (IRE). Though the overall incidence of IRE is low, due to the ever-increasing number of injections being performed, it is a complication that all retina specialists are likely to encounter. This article reviews various factors that could potentially influence the risk of IRE and discusses evidence-based strategies for management.

METHOD

PubMed was searched for keywords "intravitreal injection" and "endophthalmitis" from the period of 1995-2021. Relevant articles were reviewed and selected articles were analyzed with respect to the incidence, potential preventive factors, clinical presentation, microbial profile, management, and outcomes for IRE.

RESULTS

There is strong consensus supporting the use of povidone iodine topical antiseptic, eyelid retraction away from the injection site, and avoiding treatment of eyes with active surface or eyelid disease, but there is less agreement on the use of face masks versus "no-talking" policies and optimal anesthetic technique. Current evidence comparing tap and inject or early vitrectomy for treatment of IRE is inadequate to determine an optimal treatment strategy.

CONCLUSION

Intravitreal injections are sight saving, but even using established prophylactic measures there remains a small but real risk of infectious injection-related complications. Further investigations comparing tap and inject versus vitrectomy may help to establish optimal treatment, although the rarity of IRE makes designing adequately powered prospective trials a difficult task.

Conjunctival sac bacterial culture of patients using levofloxacin eye drops before cataract surgery: a real-world, retrospective study

Background

The use of antibiotics preoperatively is effective to decrease the incidence of ocular bacterial infections but may lead to high resistance rate, especially on patients with multi-risk clinical factors. This study systematically analyzed real-world data (RWD) of patients to reveal the association between clinical factors and conjunctival sac bacterial load and offer prophylaxis suggestions.

Methods

We retrieved RWD of patients using levofloxacin eye drops (5 mL: 24.4 mg, 4 times a day for 3 days) preoperatively. Retrieved data included information on the conjunctival sac bacterial culture, sex, presence of hypertension and diabetes mellitus (DM), and history of hospital-based surgeries. Data was analyzed using SPSS 24.0.

Results

RWD of 15,415 cases (patients) were retrieved. Among these patients, 5,866 (38.1%) were males and 9,549 (61.9%) females. 5,960 (38.7%) patients had a history of hypertension, and 3,493 (22.7%) patients had a history of DM. 7,555 (49.0%) patients had a history of hospital-based operations. There were 274 (1.8%) positive bacterial cultures. Male patients with hypertension and DM may be at increased risk of having positive bacterial cultures (P < 0.05). Staphylococcus epidermidis (n = 56, 20.4%), Kocuria rosea (n = 37, 13.5%), and Micrococcus luteus (n = 32, 11.7%) were the top 3 isolated strains. Most bacterial strains were resistant to various antibiotics except rifampin, and 82.5% (33 of 40 isolates) of Staphylococcus epidermidis isolates had multidrug antibiotic resistance. Numbers of culture-positive Staphylococcus epidermidis isolates in the male group and non-DM group were greater than those in the female and DM groups, respectively. Micrococcus luteus (n = 11, 8.8%) was found less frequently in non-hypertension group than in hypertension group.

Conclusion

Sex (Male) and the presence of hypertension and DM are risk factors for greater conjunctival sac bacterial loads. We offer a prophylactic suggestion based on the combined use of levofloxacin and rifampin. However, this approach may aggravate risk of multidrug resistance.

The short-term effect of different chlorhexidine forms versus povidone iodine mouth rinse in minimizing the oral SARS-CoV-2 viral load: An open label randomized controlled clinical trial study

Several investigations evaluated the possibility of different types of mouth wash rinse in minimizing the SARS-CoV-2 load. However, results still controversial. The study aim is to assess the short-term efficiency of several over-the-counter mouth rinses and lozenges in minimizing the salivary viral load for SARS-CoV-2 in patients with confirmed COVID-19 in comparison to saline. This is a randomized controlled clinical trial with 4 arms. The recruited cases were randomized using a simple randomization technique and were assigned to chlorhexidine digluconate mouth rinse (CHX mouth rinse), 2 mg of chlorhexidine digluconate lozenges (CHX lozenges), povidone iodine mouth rinse (PVP-I mouth rinse) or saline as a control group. Saliva were collected from all study subjects by passive drool technique at two time points. First, prior to intervention with mouth rinse or the lozenges, the baseline saliva sample was collected. Second saliva samples were collected immediately after the mouth rinse. Real time PCR was conducted and the value threshold cycle (Ct) for each sample was recorded. Majority of the participants had an education level of high school or less (60%), were married (68.3), males (58.3%), and non-smokers (58.5%). No statistically significant differences between groups at the two times test (P > .05). However, a significant decrease of salivary viral load in all four groups combined (P-value for E genes = .027, and for S genes = .006), and in PVP-I mouth rinse specifically (P = .003 and P = .045, respectively). Povidone iodine mouth rinse showed a potential influence on the reduction of the viral load on a short-term basis. However, longer-term studies of the effect of these products should be conducted.

Particle Design and Inhalation Delivery of Iodine for Upper Respiratory Tract Infection Therapy

Diseases caused by upper respiratory tract (URT) and pulmonary infections have been a serious threat to human health for millennia and lack of targeted effective therapeutic techniques. In this study, two kinds of cyclodextrin particles with typical particle shapes of nanocubes and microbars were synthesized through a facile process. Subsequently, the particles were used as carriers for loading and stabilizing iodine and characterizations were performed to demonstrate the loading mechanism. Next-generation impactor (NGI) experiments showed that iodine-loaded microbars (I₂@microbars) had a deposition rate of 79.75% in URT, while iodine-loaded nanocubes (I₂@nanocubes) were delivered to the deep lungs with a fine particle fraction (FPF) of 46.30%. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) indicated that the iodine-loaded nanocubes and microbars had similar bactericidal effect to povidone iodine solution. Cell viability studies and extracellular pro-inflammatory factor (TNF-α, IL-1β, IL-6) evaluations demonstrate noncytotoxic effects of the blank carriers and anti-inflammatory effects of iodine-loaded samples. The irritation of the rat pharynx by I₂@microbars was evaluated for the behavioral observations, body weight changes, histopathological studies, and TNF-α, IL-1β, and IL-6 levels in pharyngeal tissues. The results showed that I₂@microbars had no irritation to rat pharyngeal tissues at therapeutic doses. In conclusion, the present study provides novel treatment of URT infections via supramolecular cyclodextrin carriers for URT local therapy with iodine loading by a solvent-free method, which enhances the stability and reduces the inherent irritation without inhibiting their antimicrobial effects.

Safety of Endoscopic Transsphenoidal Pituitary Surgery during the COVID-19 Pandemic and Comparison to the Pre-Pandemic Era

Objective The COVID-19 pandemic has caused significant disruption to the surgical care of patients with pituitary tumors. Guidance issued early during the pandemic suggested avoiding transnasal approaches to minimize risks of transmitting COVID-19 to health care professionals involved in these procedures.

Methods This observational, single-center study compares results of endoscopic transsphenoidal approach (TSA) for pituitary tumors since the start of the pandemic to a pre-pandemic period. Anesthetic time, surgical time, and complication rates were compared. Newly acquired COVID-19 infections and transmission rates to patients and staff were reviewed. Data were analyzed by using the independent t-test, Mann–Whitney U test, and Pearson Chi-square test, significance set at p <0.05.

Results Over a 12-month period, a total of 50 and 69 patients underwent endoscopic TSA for pituitary tumor during and before the pandemic, respectively. All patients tested negative for COVID-19 preoperatively. Median duration of anesthesia was 35 minutes (interquartile range [IQR]: 22) during the pandemic and 25 minutes (IQR: 8, p = 0.0002) pre-pandemic. Median duration of surgery was 70 minutes (IQR: 28) during the pandemic and 79 minutes (IQR: 33.75, p = 0.126) pre-pandemic. There were no statistically significant differences between intraoperative CSF leaks and complication rates. No staff members tested positive for COVID-19. Three patients tested positive for COVID-19 postdischarge, but the infections were community acquired.

Conclusion In contrast to published guidelines, adequate preoperative testing, a multidisciplinary approach and the implementation of standardized protocols and vaccination against COVID-19 allow for endoscopic transsphenoidal surgery to be performed safely in patients with pituitary pathology during the pandemic.

Efficacy of Three Povidone Iodine Formulations against Cutibacterium acnes Assessed through In Vitro Studies: A Preliminary Study

Cutibacterium acnes (C. acnes, formerly known as Propionibacterium acnes) is the major causative agent of prosthetic joint infections (PJI). Treatment of PJI with antibiotics is difficult due to antibiotic resistance and adverse side effects on patients’ health. Proper disinfection of the surgical site using a variety of povidone iodine formulations could prevent C. acnes infection. In the current study, the efficacy of the three povidone iodine (PVP-I) formulations, viz: PVP-I 10% dermic solution, PVP-I 5% alcoholic solution and PVP-I 4% scrub, was tested against C. acnes, in vitro, in the presence of interfering substances mimicking soiling conditions. C. acnes strain ATCC 6919 was used to test the bactericidal activity of the povidone iodine formulations according to the modified dilution-neutralization method described in French Norm EN standard 13727. A 3-log reduction in the bacterial cell count in 60 s was considered to be significant. The results showed that under experimental conditions, the three PVP-I formulations displayed bactericidal activity against the micro-organism, Cutibacterium acnes, and that the lowest concentration of povidone-iodine active against C. acnes was 0.4%. These results are encouraging as PVP-I offers a low-cost and efficient method of disinfection.

Natural Rubber (NR) Latex Films with Antimicrobial Properties for Stethoscope Diaphragm Covers

Systematic disinfection of the stethoscope diaphragm is required to ensure that it does not act as a vector for cross-transmission of health-related diseases. Thus, an antimicrobial latex film could be used as a cover to inhibit pathogenic bacteria from growing on its surface. The aim of this work is to determine the antimicrobial activity and mechanical properties of antimicrobial natural rubber (NR) latex films with different types of antimicrobial agents (mangosteen peel powder (MPP), zinc oxide nanoparticles (ZnO NP), and povidone-iodine (PVP-I)). The antimicrobial loading was varied from 0.5, to 1.0, and 2.0 phr to monitor the effective inhibition of Gram-negative bacteria and fungi growth. For MPP and PVP-I antimicrobial agents, a loading of 2.0 phr showed good antimicrobial efficacy with the largest zone of inhibition. Simultaneously, ZnO NP demonstrated excellent antimicrobial activity at low concentrations. The addition of antimicrobial agents shows a comparable effect on the mechanical properties of NR latex films. In comparison to control NR latex film (29.41 MPa, 48.49 N/mm), antimicrobial-filled films have significantly greater tensile and tear strengths (MPP (33.84 MPa, 65.21 N/mm), ZnO NP (31.79 MPa, 52.77 N/mm), and PVP-I (33.25 MPa, 50.75 N/mm). In conclusion, the addition of antimicrobial agents, particularly ZnO NP, can be a better choice for NR latex films because they will serve as both an activator and an antimicrobial. In a clinical context, with regard to frequently used medical equipment such as a stethoscope, such an approach offers significant promise to aid infection control.

Virucidal Effect of Povidone Iodine on SARS-CoV-2 in Nasopharynx: An Open-label Randomized Clinical Trial

To assess the virucidal effect of povidone iodine (PVP-I) on severe acute respiratory syndrome coronavirus 2 (SARS CoV-2) located in the nasopharynx and suitable dose-formulation for nasal application were the purpose of this clinical trial. This single-center, open-label randomized clinical trial with a 7-arm parallel-group design was conducted in Dhaka Medical College (DMC) Hospital. A total of 189 reverse transcription-polymerase chain reaction (RT-PCR)-confirmed SARS CoV-2 positive cases aged 12–90 years with symptoms was sequentially enrolled following randomization. Nasopharyngeal clearance of SARS-CoV-2 was tested against PVP-I nasal irrigation (NI) at diluted concentrations of 0.4%, 0.5% and 0.6%, and PVP-I nasal spray (NS) at diluted concentrations of 0.5% and 0.6%. All groups were compared to the corresponding controls (distilled water). Written informed consent was ensured before participation. All procedures were conducted in after ethical clearance from the Ethical Review Board and in accordance with the Declaration of Helsinki. Viral clearance in a repeat RT-PCR (qualitative) was the primary outcome, and occurrence of any adverse event following administration of testing drug was considered as the secondary outcome. Analysis was performed using SPSS (Version 26). All cases were randomized into seven groups and each group consists of 27-patient. Mean age of the cases 43.98 ± 12.67 years (SD). All strength of NI were effective in nasopharyngeal clearance compared to the control (0.4%, p = 0.006; 0.5%, p < 0.001; and 0.6%, p = 0.018). Similarly, all strength of the NS is also effective than control (0.5%, p =  < 0.001; and 0.6%, p ≤ 0.001). Highest nasopharyngeal clearance was observed in patients using 0.5% NI (n = 25, 92.6%, p = 0.018). Nasal irritation was the single most adverse event recorded in this trial and found in two patients using 0.4%, and 0.6% PVP-I NI, respectively. Both PVP-I NS and NI are effective for nasopharyngeal clearance in-vivo. However, further community trials are needed to repurpose these solutions as preventive agents against SARS-CoV2.

Ethical clearance memo no ERC-DMC/ECC/2020/93.

Trial registration NCT Identifier number NCT04549376.

Oral squamous cell carcinoma with essential thrombocythemia and positive JAK2 (V617F) mutation

Essential thrombocythemia is a condition caused by a high platelet count and a positive JAK2 (V617F) mutation. There is an increasing occurrence of malignancy, such as oral squamous cell carcinoma (OSCC), in patients with essential thrombocythemia. The objective of this case report is to document the novel instance of a patient with OSCC after being diagnosed with essential thrombocythemia and a positive JAK2 (V617F) mutation. The patient was a 42-year-old female who complained of an ulcer and pain in the dextral lateral tongue for three months. After two weeks, the pain diminished; however, there was swelling and tenderness on the ulcer. The patient was diagnosed with essential thrombocythemia and a positive JAK2 (V617F) mutation and began undergoing hydroxyurea therapy three months prior to the OSCC diagnosis. The diagnosis of OSCC was based on exfoliative cytology and MRI. The patient was treated with an antiseptic mouthwash to prevent secondary infection and referred to an oncologist to manage the OSCC. It is possible to use the suspected markers of thrombocytosis and a positive JAK2 (V617F) mutation to define the OSCC diagnosis.

Effect of halogenated indoles on biofilm formation, virulence, and root surface colonization by Agrobacterium tumefaciens

Agrobacterium tumefaciens is a plant pathogen that causes crown gall disease in several plant species by transferring its T-DNA to the host genome. Its chemotactic response to a range of chemical compounds released by hosts facilitates its colonization to host surfaces, and thus, novel anti-agrobacterium compounds are needed to prevent its biofilm formation. Here, we investigated 83 indole derivatives against A. tumefaciens, and based on the screening, 4-chloroindole, 6-iodoindole, and 5-chloro-2-methyl indole were selected as candidates that at 50 μg mL^-1 significantly inhibited the adherence and biofilm formation of A. tumefaciens to abiotic (nitrocellulose and polystyrene) and biotic (roots of Brassica juncea) surfaces. Furthermore, they reduced bacterial growth in a time and concentration-dependent manner and significantly reduced log CFU mL^-1 and survival (%). Changes in biofilm morphologies and biomasses, thicknesses, and substratum coverages were determined, and 2-D and 3-D analyses were performed using a crystal violet assay and bright field, CLSM, and SEM microscopies. Virulence factors such as swimming motility, exopolysaccharide, and exo-protease production, and cell surface hydrophobicity were markedly inhibited by the three compounds. Transcriptional analysis showed multi-fold downregulation of biofilm, virulence, motility, and stress-related genes; however, the degrees of these downregulations were variably affected. B. juncea seed germination was only severely affected by 4-chloroindole. This study demonstrates the promising antibiofilm and antivirulence activities of the three indole derivatives tested and their potentials for targeting and curbing A. tumefaciens infections.

Povidone iodine suppresses LPS-induced inflammation by inhibiting TLR4/MyD88 formation in airway epithelial cells

Povidone-iodine (PVP-I) is an antiseptic and a disinfectant with broad-spectrum antimicrobial activity against various pathogens. However, it is unclear whether PVP-I nasal instillation can suppress mucosal inflammation in non-eosinophilic chronic rhinosinusitis (CRS) mice. This study aimed to explore the anti-inflammatory effects and underlying molecular mechanism of PVP-I on lipopolysaccharide-stimulated airway epithelial cells and investigate whether nasal instillation of PVP-I can suppress mucosal inflammation in non-eosinophilic CRS mice. Inflammation-related molecules in the nasal epithelial cells and non-eosinophilic CRS mice were measured by enzyme-linked immunosorbent assay, western blotting, quantitative real-time polymerase chain reaction, immunoprecipitation, and histopathological analysis. PVP-I blocked expressions of various inflammation-related molecules, such as NLRP3, NF-κB-p65, caspase-1, and IL-1β. Translocation of NF-κB to the nucleus, and assembly of NLRP3/ASC complexes in the nasal epithelial cells and non-eosinophilic CRS mice were also restricted. Notably, PVP-I strongly blocked the receptor co-localization of TLR4 and MyD88 in the epithelial cells of nasal mucosa. We demonstrated that PVP-I significantly attenuated inflammatory molecules and cytokines via blocking the formation of TLR4 and MyD88 complexes during LPS-induced mucosal inflammation in non-eosinophilic CRS.

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.

Toxicological evaluation of repeated administration of povidone iodine in cockerels

Povidone-iodine (Polidine®) is a synthetic broad-spectrum antiseptic being applied topically to treat wounds and prevent their infection. It has been however reported with the assertions that it is effective in the treatment of infectious bursa disease (IBD) when administered orally by practicing Veterinarians and other poultry handlers. Acute kidney injury has been reported also with povidone iodine ingestion. Hence, in this study, graded dose administration was conducted to ascertain its safety profile. Forty chicks were obtained from a poultry hatchery in Ibadan, Oyo State. They were randomly divided into four (4) groups of ten chicks each. Group I served as negative control, groups II, III and IV were administered Polidine® at 1 mL/50 L, 1 mL/25 L, and 1 mL/10 L of water respectively for 7 days. Blood samples were collected on Days 3 and 7 post administration for determination of haematological and biochemical parameters. Liver and Kidney tissues were harvested following termination of the experiment and processed for histopathological examination. Results revealed no significant (p > 0.05) effect in the haematological and biochemical parameters of cockerels treated with Povidone iodine at 1 mL/50 and 25 L of water. On histopathological examination no lesion was also observed in the liver and kidney tissues of groups I, II and III (normal control, 1 mL/50 and 25 L respectively) when compared to group IV (1 mL PI /50 L of water) where lesions were recorded. Hence, this study has shown the relative safety of povidone iodine at different doses in cockerels.

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Povidone iodine treatment at 1 mL/50 and 25 L of water had no haematological effect.

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Povidone iodine administered at 1 mL/50 and 25 L of water had no biochemical effect.

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Povidone iodine given at 1 mL/50 and 25 L of water had no histopathological lesions.

In vitro inactivation of SARS-CoV-2 using a povidone-iodine oral rinse

BACKGROUND

Healthcare professionals, especially dentists and dental hygienists, are at increased risk for contracting severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) through air-borne particles and splatter. This study assessed the in vitro virucidal activity of 0.5% (w/v) povidone-iodine (PVP-I) oral rinse against SARS-CoV-2 to demonstrate its utility as a professional oral rinse.

METHODS

A 0.5% (w/v) PVP-I oral rinse formulation, placebo oral rinse, and positive (70% [v/v] ethanol and water) and negative (water) controls were assessed using the time-kill method. SARS-CoV-2 was propagated in Vero 76 host cells. Following neutralization validation, triplicate tests were performed for each test formulation and virucidal activity measured at 15, 30, and 60 s and 5 min.

RESULTS

The 0.5% (w/v) PVP-I oral rinse demonstrated effective in vitro virucidal activity against SARS-CoV-2 as early as 15 s after exposure; viral titer was reduced to < 0.67 log₁₀ 50% cell culture infectious dose (CCID₅₀)/0.1 mL (log₁₀ reduction of > 4.0) at 30 s, whereas the placebo oral rinse reduced the SARS-CoV-2 viral titer to 4.67 and 4.5 log₁₀ CCID₅₀/0.1 mL at the 15- and 30-s time points, with a log₁₀ reduction of 0.63 and 0.17, respectively. No toxicity or cytotoxic effects against Vero 76 host cells were observed with the 0.5% (w/v) PVP-I oral rinse; positive and negative controls performed as expected.

CONCLUSIONS

In vitro virucidal activity of 0.5% (w/v) PVP-I oral rinse against SARS-CoV-2 was demonstrated. Rapid inactivation of SARS-CoV-2 was observed with 0.5% (w/v) formulation with a contact duration of 15 s. Clinical investigations are needed to assess the effectiveness of PVP-I oral rinse against SARS-CoV-2 in dental practice.

Antiseptic versus non-antiseptic solutions for preventing infection in acute traumatic wounds: a systematic review

OBJECTIVE

To compare the effectiveness of antiseptic solutions to that of non-antiseptic solutions in reducing wound infection rate, reducing bacterial load and improving wound healing.

METHOD

We searched PubMed MEDLINE, Cochrane Central Register of Controlled Trials (CENTRAL), ProQuest Medical Database and medRxiv for randomised controlled trials (RCTs) comparing antiseptic solutions with non-antiseptic solutions in simple, uncomplicated acute traumatic wounds. Qualitative data synthesis was employed. Risk of bias was assessed and GRADE assessment was used to evaluate quality of evidence.

RESULTS

In this systematic review, four studies with a total of 875 participants were included, of which two studies showed a significant reduction of wound infection rate using povidone-iodine (p=0.001 and p=0.03). The use of non-antiseptic solutions significantly increased bacterial load on acute traumatic wounds (p=0.0001). The quality of evidence was very low. No studies reported on wound healing outcome.

CONCLUSION

No robust conclusions can be implemented in clinical practice. Future studies are needed to compare the use of antiseptic and non-antiseptic solutions in acute traumatic wounds.

Activity of Ozonated Water in Sterilising and Disinfecting Dental Unit Water Pipelines System: A Comparative Study

PURPOSE

A number of disinfectants and sanitisers are used in dentistry, and there are numerous commercial solutions available. Nonetheless, because each cleaning solution has its own set of indications and limits, there is no one-size-fits-all approach for processing all types of dental equipment. Functional water, such as electrolysed hypochlorite microbubbled water, efficiently eliminates and sterilises biofilms. The objective of the study was to evaluate whether ozonated water could be used to sterilise and disinfect dental-unit water pipelines (DUWP) that had been contaminated with micro-organisms, including Gram-positive and Gram-negative bacilli and cocci.

MATERIALS AND METHODS

Three different groups were formed: group A - ozonated water (Cantoosh); group B - 1% povidine iodine; and group C: conventional distilled water. Group A was the test group, group B the control group, and group C was the positive control group. The water sterilising system was replaced with the appropriate sterilising agent as per the allocated group classification, with 2 min of purging, so that the complete DUWP was filled with the water sterilising system. Samples were collected and analysed, along with a 2-min purge after 24 h, 7 days and 21 days, at the 3 outlet (OL) points: the 3-way syringe at the dental tray(OL1), the cup filler (OL2), and the 3-way syringe of the assistant zone (OL3). Repeated measures ANOVA was used to test for statistical significance between colony-forming units of control and experimental groups (p < 0.05).

RESULTS

The cup filler yielded higher counts than did the 3-way syringe at the dental tray (OL1) (6.40 and 8.05 on the log scale, respectively). A statistically significant difference in the CFUs was also observed between samples taken after 24 h vs 21 days between groups A, B and C.

CONCLUSION

The findings showed that exposing DUWP tube systems to ozonated water for an extended length of time drastically lowered the number of microorganisms adhering to their surfaces.